Light-emitting element, light-emitting device, electronic device, lighting device, and novel organic compound

Abstract

The present invention relates to a light-emitting element, a light-emitting device, an electronic device, a lighting device, and a novel organic compound. One embodiment of the present invention is a light-emitting element including an EL layer between a pair of electrodes. The EL layer includes a first compound and a second compound. The first compound is a phosphorescent iridium metal complex having a LUMO energy level of greater than -3.5 eV and less than -2.5 eV, and the second compound is an organic compound containing a pyrimidine skeleton. In addition, another embodiment of the present invention is a light-emitting element including an EL layer between a pair of electrodes. The EL layer includes a first compound and a second compound. The first compound is a phosphorescent iridium metal complex containing a diazine skeleton, and the second compound is an organic compound containing a pyrimidine skeleton.

Description

[0001] This application is a further divisional application of the divisional application filed based on the invention patent application with the application date of August 21, 2012, application number 201280001907.9, and invention name “Light-emitting element, light-emitting device, electronic device, lighting device and new organic compound” (the application date is August 21, 2012, application number 201710429638.0, and invention name “Light-emitting element, light-emitting device, electronic device, lighting device and new organic compound”). Technical Field

[0002] The present invention relates to a light-emitting element, a light-emitting device, an electronic device, a lighting device and a novel organic compound. Background Art

[0003] In recent years, research and development of light-emitting devices that utilize electroluminescence (EL) have become increasingly intense. The basic structure of these light-emitting devices consists of a layer containing a light-emitting material sandwiched between a pair of electrodes. Applying a voltage to the device produces light from the light-emitting material.

[0004] Because this light-emitting element is self-luminous, it offers advantages such as higher pixel visibility than LCDs and the absence of a backlight. Consequently, it is considered suitable for flat-panel display applications. Another key advantage of this light-emitting element is its ability to be manufactured in a thin and lightweight form. Furthermore, its extremely fast response time is a hallmark of this element.

[0005] Furthermore, since these self-luminous light-emitting elements can be formed into a film, they can easily achieve surface emission, enabling the creation of large-area elements that utilize surface emission. This feature is difficult to achieve with point light sources such as incandescent lamps and LEDs, or line light sources such as fluorescent lamps, making them highly valuable as surface light sources for applications such as lighting.

[0006] The aforementioned light-emitting elements utilizing electroluminescence are broadly categorized based on whether the luminescent substance is an organic compound or an inorganic compound. In organic EL elements that use an organic compound as the luminescent substance and have a layer containing the organic compound disposed between a pair of electrodes, application of a voltage to the light-emitting element causes electrons and holes to be injected from the cathode and anode, respectively, into the layer containing the luminescent organic compound, causing current to flow. The injected electrons and holes then excite the organic compound, resulting in luminescence from the excited organic compound.

[0007] The excited state formed by the organic compound can be a singlet excitation or a triplet excitation, and the excited state from the singlet excitation (S * ) is called fluorescence, while the emission from triplet excitation (T* ) is called phosphorescence. In addition, in a light-emitting element, the statistical generation ratio of singlet excitation and triplet excitation is considered to be S * :T * =1:3.

[0008] In compounds that convert singlet excitation energy into luminescence (hereinafter referred to as fluorescent compounds), only luminescence (fluorescence) from singlet excitation is observed at room temperature, and luminescence (phosphorescence) from triplet excitation is not observed. * :T * =1:3, and the theoretical limit of the internal quantum efficiency (the ratio of generated photons to injected carriers) in a light-emitting element using a fluorescent compound is considered to be 25%.

[0009] On the other hand, in compounds that convert triplet excitation energy into luminescence (hereinafter referred to as phosphorescent compounds), luminescence (phosphorescence) from triplet excitation is observed. In addition, in phosphorescent compounds, since intersystem crossing (i.e., transfer from singlet excitation to triplet excitation) easily occurs, the internal quantum efficiency can theoretically be increased to 100%. In other words, a higher emission efficiency than that of fluorescent compounds can be obtained. For this reason, in order to achieve high-efficiency light-emitting elements, in recent years, intensive research and development of light-emitting elements using phosphorescent compounds has been carried out.

[0010] When the above-mentioned phosphorescent compound is used to form the light-emitting layer of a light-emitting element, in order to suppress concentration quenching of the phosphorescent compound or quenching caused by triplet-triplet annihilation, the light-emitting layer is usually formed so that the phosphorescent compound is dispersed in a matrix composed of other compounds. In this case, the compound used as the matrix is called the host material, and the compound dispersed in the matrix, such as the phosphorescent compound, is called the guest material (dopant).

[0011] When a phosphorescent compound is used as a guest material, a property required of the host material is to have a higher triplet excitation energy (energy difference between the ground state and triplet excitation) than that of the phosphorescent compound.

[0012] Furthermore, since singlet excitation energy (the energy difference between the ground state and the singlet excitation state) is higher than triplet excitation energy, substances with high triplet excitation energy also have high singlet excitation energy. Therefore, such substances with high triplet excitation energy are also effective in light-emitting devices using fluorescent compounds as the luminescent substance.

[0013] As a host material or electron transport material used when a phosphorescent compound is a guest material, compounds having pyrimidine or the like as a partial structure have been studied (for example, Patent Document 1).

[0014] Furthermore, a compound is disclosed in which, when a phosphorescent compound is used as a guest material, a compound comprising a combination of a carbazole skeleton and a nitrogen-containing aromatic heterocycle is used as a host material (for example, Patent Document 2).

[0015] [Patent Document 1] Japanese Patent Application Publication No. 2003-45662

[0016] [Patent Document 2] International Patent Application Publication No. 2011-046182

[0017] As reported in Patent Document 1 or Patent Document 2, research on host materials and guest materials for phosphorescent compounds is actively underway. However, from the perspective of light-emitting elements, there is still room for improvement in terms of luminous efficiency, reliability, luminous properties, synthesis efficiency, and cost, and therefore, there is a need for the development of more superior light-emitting elements. Summary of the Invention

[0018] In view of the above problems, one object of one embodiment of the present invention is to provide a light-emitting element comprising a light-emitting substance for a light-emitting layer and a novel organic compound serving as a host material for dispersing the light-emitting substance. In particular, one object of one embodiment of the present invention is to provide an organic compound suitable as a host material when a phosphorescent iridium metal complex is used as the light-emitting substance.

[0019] Another object of one embodiment of the present invention is to provide a light-emitting device, an electronic device, and a lighting device including the light-emitting element.

[0020] One embodiment of the present invention is a light-emitting element including an EL layer between a pair of electrodes. The EL layer includes a first compound and a second compound. The first compound is a phosphorescent iridium metal complex having a LUMO (lowest unoccupied molecular orbital) energy level of not less than -3.5 eV and not more than -2.5 eV. The second compound is an organic compound containing a pyrimidine skeleton.

[0021] Another embodiment of the present invention is a light-emitting element including an EL layer between a pair of electrodes. The EL layer includes a first compound and a second compound. The first compound is a phosphorescent iridium metal complex containing a diazine skeleton. The second compound is an organic compound containing a pyrimidine skeleton.

[0022] Another embodiment of the present invention is a light-emitting element including an EL layer between a pair of electrodes. The EL layer includes a first compound and a second compound. The first compound is a phosphorescent iridium metal complex containing a diazine skeleton and having a LUMO energy level of not less than -3.5 eV and not more than -2.5 eV. The second compound is an organic compound containing a pyrimidine skeleton.

[0023] Another embodiment of the present invention is a light-emitting element comprising a plurality of EL layers between a pair of electrodes. At least one of the plurality of EL layers comprises a first compound and a second compound. The first compound is a phosphorescent iridium metal complex containing a diazine skeleton and having a LUMO level of not less than -3.5 eV and not more than -2.5 eV. The second compound is an organic compound containing a pyrimidine skeleton.

[0024] In each of the above structures, it is preferred that the diazine skeleton forms a coordination bond with iridium. Furthermore, the diazine skeleton is preferably a pyrimidine skeleton.

[0025] In a light-emitting element including a guest material of the first compound and a host material of the second compound, when the guest material and the host material both have the same pyrimidine skeleton, carriers are efficiently transferred from the host material to the guest material.

[0026] Furthermore, since the second compound of one embodiment of the present invention is a heterocyclic compound and has a high electron-transporting property, it can be used not only as an EL layer of a light-emitting element but also as an electron-transporting layer or an electron-injecting layer.

[0027] Furthermore, when multiple EL layers are provided between a pair of electrodes, a charge generation layer can be placed between the EL layers to achieve high-luminance emission while maintaining a low current density. This low current density allows for a long-lasting device.

[0028] In addition, in each of the above structures, the first compound is preferably a phosphorescent iridium metal complex having a HOMO (highest occupied molecular orbital) energy level of not less than -6.0 eV and not more than -5.0 eV. By adopting this structure, the phosphorescent iridium metal complex easily captures holes, so the change in the hole mobility of the light-emitting element over time is suppressed. As a result, it is possible to expect a longer service life of the element.

[0029] In each of the above structures, the molecular weight of the second compound is preferably 2000 or less. For example, when the second compound is deposited using a vapor deposition apparatus, a molecular weight of 2000 or less (more preferably 1000 or less) can improve the deposition efficiency. Furthermore, to stabilize the properties of the formed film, the molecular weight is preferably set to 500 or more, which is a relatively high glass transition temperature (Tg).

[0030] In addition, in each of the above structures, the second compound preferably includes at least one of a benzene skeleton, a biphenyl skeleton, a naphthalene skeleton, a carbazole skeleton, a phenanthrene skeleton, a triphenylene skeleton, a dibenzothiophene skeleton, and a dibenzofuran skeleton as a substituent. When the second compound includes the above substituent, it has a high phosphorescence energy level (also called a triplet energy level).

[0031] In addition, in each of the above structures, the second compound can be represented by the general formula (G1).

[0032]

[0033] In the general formula (G1), R 1 and R 2 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 As a substituent, at least one of a naphthalene skeleton, a phenanthrene skeleton, and a triphenylene skeleton is included. 2 At least one of hydrogen, a naphthalene skeleton, a phenanthrene skeleton, and a triphenylene skeleton is contained as a substituent.

[0034] In each of the above structures, the second compound can be represented by general formula (G2). The compound represented by the following general formula (G2) is a novel compound suitable for the second compound, and this compound is one embodiment of the present invention.

[0035]

[0036] In the general formula (G2), R 1 to R 5 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 4 represents any one of hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 5 represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 and α 4 Each of j and k independently represents a substituted or unsubstituted phenylene group.

[0037] In each of the above structures, the second compound can be represented by the general formula (G2-1). The compound represented by the following general formula (G2-1) is a novel compound suitable for the second compound, and this compound is one embodiment of the present invention.

[0038]

[0039] In the general formula (G2-1), R 1 to R 8Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 4 、Ar 6 and Ar 7 Each independently represents hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 3 , α 4 , α 6 and α 7 Each of j, k, m and n independently represents 0 or 1.

[0040] In each of the above structures, the second compound can be represented by general formula (G3). The compound represented by the following general formula (G3) is a novel compound suitable for the second compound, and this compound is one embodiment of the present invention.

[0041]

[0042] In the general formula (G3), R 1 to R 10 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 7 represents any one of hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 3 and α 7 Each of j and n independently represents a substituted or unsubstituted phenylene group.

[0043] In addition, in each of the above structures, the second compound can be represented by structural formula (300).

[0044]

[0045] In each of the above structures, the weight ratio of the second compound is preferably greater than that of the first compound. In other words, in the light-emitting element, the second compound serves as a host material and the first compound serves as a guest material.

[0046] Another embodiment of the present invention is an organic compound represented by General Formula (G4).

[0047]

[0048] In the general formula (G4), Ar 11 、Ar 12 、R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13 and Ar 14 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 , α 2 , α 8 and α 9 Each of h, i, x and y independently represents 0 or 1. 1 and E 2 Each independently represents sulfur or oxygen.

[0049] Another embodiment of the present invention is an organic compound represented by General Formula (G5).

[0050]

[0051] In the general formula (G5), Ar 11 、Ar 12 、R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13 and Ar 14 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0052] Another embodiment of the present invention is an organic compound represented by General Formula (G6).

[0053]

[0054] In the general formula (G6), R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0055] Another embodiment of the present invention is an organic compound represented by General Formula (G7).

[0056]

[0057] In the general formula (G7), R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0058] Another embodiment of the present invention is an organic compound represented by structural formula (400).

[0059]

[0060] Another embodiment of the present invention is a light-emitting element comprising the above-mentioned organic compound between a pair of electrodes. In particular, the light-emitting element preferably comprises the above-mentioned organic compound in a light-emitting layer.

[0061] In addition, the present invention includes a light-emitting device, an electronic device, and a lighting device using the above-mentioned light-emitting element. In addition, the light-emitting device in this specification includes an image display device, a light-emitting device, and a light source. In addition, the following modules are also included in the light-emitting device: a module with a connector such as FPC (Flexible Printed Circuit), TAB (Tape Automated Bonding) tape or TCP (Tape Carrier Package) installed on the panel; a module with a printed wiring board provided at the end of the TAB tape and TCP; a module with an IC (integrated circuit) directly mounted on the light-emitting element by COG (Chip On Glass).

[0062] One embodiment of the present invention can provide a light-emitting element comprising a light-emitting substance for a light-emitting layer and a novel organic compound used as a host material for dispersing the light-emitting substance. In particular, one embodiment of the present invention can provide an organic compound that is a novel organic compound suitable for use as a host material when a phosphorescent iridium metal complex is used as the light-emitting substance. In addition, one embodiment of the present invention can provide a light-emitting element having a low driving voltage and high current efficiency. According to one embodiment of the present invention, by using the above-mentioned light-emitting element, a light-emitting device, an electronic device, and a lighting device with low power consumption can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 is a diagram illustrating a light-emitting element according to one embodiment of the present invention;

[0064] Figure 2A and Figure 2B is a diagram illustrating a light-emitting element according to one embodiment of the present invention;

[0065] Figure 3 is a diagram illustrating a light-emitting element according to one embodiment of the present invention;

[0066] Figure 4A and Figure 4B is a diagram illustrating a light-emitting element according to one embodiment of the present invention;

[0067] Figure 5 is a diagram illustrating a light-emitting element according to one embodiment of the present invention;

[0068] Figure 6A and Figure 6B is a diagram illustrating a light-emitting device according to one embodiment of the present invention;

[0069] Figure 7A and Figure 7B is a diagram illustrating a light-emitting device according to one embodiment of the present invention;

[0070] Figures 8A to 8D is a diagram illustrating an electronic device according to one embodiment of the present invention;

[0071] Figures 9A to 9C This is a diagram illustrating a lighting device according to one embodiment of the present invention;

[0072] Figure 10A and Figure 10B Showing 4,6mPnP2Pm 1 H NMR spectrum;

[0073] Figure 11A and Figure 11B Graph showing the absorption and emission spectra of a toluene solution of 4,6mPnP2Pm;

[0074] Figure 12A and Figure 12B Graphs showing the absorption and emission spectra of a thin film of 4,6mPnP2Pm;

[0075] Figure 13A and Figure 13B Showing 2Ph-4,6mNP2Pm 1 H NMR spectrum;

[0076] Figure 14A and Figure 14B Graph showing the absorption and emission spectra of a toluene solution of 2Ph-4,6mNP2Pm;

[0077] Figure 15A and Figure 15B Graphs showing the absorption and emission spectra of a thin film of 2Ph-4,6mNP2Pm;

[0078] Figure 16A and Figure 16B Showing 4,6mTpP2Pm 1 H NMR spectrum;

[0079] Figure 17A and Figure 17B Graphs showing the absorption and emission spectra of a toluene solution of 4,6mTpP2Pm;

[0080] Figure 18A and Figure 18B Graphs showing the absorption and emission spectra of a thin film of 4,6mTpP2Pm;

[0081] Figure 19A and Figure 19B Showing 4,6mDBTP2Pm-II 1 H NMR spectrum;

[0082] Figure 20A and Figure 20B Graphs showing the absorption and emission spectra of a toluene solution of 4,6mDBTP2Pm-II;

[0083] Figure 21A and Figure 21B Graphs showing the absorption and emission spectra of a thin film of 4,6mDBTP2Pm-II;

[0084] Figure 22A and Figure 22B Showing 2,4DBTP2Pm-II 1 H NMR spectrum;

[0085] Figure 23A and Figure 23BGraphs showing the absorption and emission spectra of a toluene solution of 2,4DBTP2Pm-II;

[0086] Figure 24A and Figure 24B Graphs showing the absorption and emission spectra of a thin film of 2,4DBTP2Pm-II;

[0087] Figure 25A and Figure 25B Showing 2,5DBTP2Pm-II 1 H NMR spectrum;

[0088] Figure 26A and Figure 26B Graphs showing the absorption and emission spectra of a toluene solution of 2,5DBTP2Pm-II;

[0089] Figure 27A and Figure 27B Graphs showing the absorption and emission spectra of a thin film of 2,5DBTP2Pm-II;

[0090] Figure 28A and Figure 28B Showing 4,6mDBTP2Pm-III 1 H NMR spectrum;

[0091] Figure 29A and Figure 29B Graph showing the absorption and emission spectra of a toluene solution of 4,6mDBTP2Pm-III;

[0092] Figure 30A and Figure 30B Graphs showing the absorption and emission spectra of a thin film of 4,6mDBTP2Pm-III;

[0093] Figure 31A and Figure 31B Showing 4,6mDBFP2Pm-II 1 H NMR spectrum;

[0094] Figure 32A and Figure 32B Graphs showing the absorption and emission spectra of a toluene solution of 4,6mDBFP2Pm-II;

[0095] Figure 33A and Figure 33B Graphs showing the absorption and emission spectra of a thin film of 4,6mDBFP2Pm-II;

[0096] Figure 34A and Figure 34B Showing 2,4DBFP2Pm-II 1 H NMR spectrum;

[0097] Figure 35A and Figure 35B Graphs showing the absorption and emission spectra of a toluene solution of 2,4DBFP2Pm-II;

[0098] Figure 36A and Figure 36B Graphs showing the absorption and emission spectra of a thin film of 2,4DBFP2Pm-II;

[0099] Figure 37A and Figure 37B Showing 2,5DBFP2Pm-II 1 H NMR spectrum;

[0100] Figure 38A and Figure 38B Graphs showing the absorption and emission spectra of a toluene solution of 2,5DBFP2Pm-II;

[0101] Figure 39A and Figure 39B Graphs showing the absorption and emission spectra of a thin film of 2,5DBFP2Pm-II;

[0102] Figure 40 is a diagram illustrating a light-emitting element 1 of an embodiment;

[0103] Figure 41 is a graph showing current density-luminance characteristics of light-emitting element 1;

[0104] Figure 42 is a graph showing voltage-luminance characteristics of light-emitting element 1;

[0105] Figure 43 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 1;

[0106] Figure 44 is a graph showing the voltage-current characteristics of the light-emitting element 1;

[0107] Figure 45 is a diagram showing the luminance-chromaticity coordinate characteristics of light-emitting element 1;

[0108] Figure 46 is a graph showing the luminance-power efficiency characteristics of the light-emitting element 1;

[0109] Figure 47 is a diagram showing an emission spectrum of light-emitting element 1;

[0110] Figure 48 is a diagram showing time-normalized luminance characteristics of light-emitting element 1;

[0111] Figure 49is a diagram showing the time-voltage characteristics of the light emitting element 1;

[0112] Figures 50A to 50C are diagrams illustrating light-emitting elements 2 to 7 of the embodiment;

[0113] Figure 51 is a graph showing the current density-luminance characteristics of the light-emitting element 2;

[0114] Figure 52 is a diagram showing the voltage-luminance characteristics of the light-emitting element 2;

[0115] Figure 53 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 2;

[0116] Figure 54 is a diagram showing the voltage-current characteristics of the light emitting element 2;

[0117] Figure 55 is a diagram showing the luminance-chromaticity coordinate characteristics of light-emitting element 2;

[0118] Figure 56 is a graph showing the luminance-power efficiency characteristics of light-emitting element 2;

[0119] Figure 57 is a diagram showing the emission spectrum of light-emitting element 2;

[0120] Figure 58 is a graph showing the current density-luminance characteristics of the light-emitting element 3;

[0121] Figure 59 3 is a graph showing the voltage-luminance characteristics of the light-emitting element 3;

[0122] Figure 60 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 3;

[0123] Figure 61 is a diagram showing the voltage-current characteristics of the light emitting element 3;

[0124] Figure 62 is a diagram showing the luminance-chromaticity coordinate characteristics of the light-emitting element 3;

[0125] Figure 63 is a graph showing the luminance-power efficiency characteristics of the light-emitting element 3;

[0126] Figure 64 is a diagram showing the emission spectrum of light-emitting element 3;

[0127] Figure 65 is a diagram showing the current density-luminance characteristics of the light-emitting element 4;

[0128] Figure 664 is a graph showing the voltage-luminance characteristics of the light emitting element 4;

[0129] Figure 67 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 4;

[0130] Figure 68 is a diagram showing the voltage-current characteristics of the light emitting element 4;

[0131] Figure 69 is a diagram showing the luminance-chromaticity coordinate characteristics of the light-emitting element 4;

[0132] Figure 70 is a diagram showing the brightness-power efficiency characteristics of the light emitting element 4;

[0133] Figure 71 is a diagram showing an emission spectrum of light-emitting element 4;

[0134] Figure 72 is a graph showing the current density-luminance characteristics of the light-emitting element 5;

[0135] Figure 73 5 is a graph showing the voltage-luminance characteristics of the light-emitting element 5;

[0136] Figure 74 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 5;

[0137] Figure 75 is a diagram showing the voltage-current characteristics of the light emitting element 5;

[0138] Figure 76 is a diagram showing the luminance-chromaticity coordinate characteristics of the light-emitting element 5;

[0139] Figure 77 is a diagram showing the brightness-power efficiency characteristics of the light-emitting element 5;

[0140] Figure 78 is a diagram showing the emission spectrum of light-emitting element 5;

[0141] Figure 79 is a diagram showing the current density-luminance characteristics of the light-emitting element 6;

[0142] Figure 80 1 is a diagram showing voltage-luminance characteristics of light emitting element 6;

[0143] Figure 81 is a graph showing the luminance-current efficiency characteristics of the light-emitting element 6;

[0144] Figure 82 is a diagram showing the voltage-current characteristics of the light emitting element 6;

[0145] Figure 83is a diagram showing the luminance-chromaticity coordinate characteristics of the light-emitting element 6;

[0146] Figure 84 is a graph showing the brightness-power efficiency characteristics of the light-emitting element 6;

[0147] Figure 85 is a diagram showing the emission spectrum of light-emitting element 6;

[0148] Figure 86 is a graph showing the current density-luminance characteristics of the light-emitting element 7;

[0149] Figure 87 is a diagram showing the voltage-luminance characteristics of the light-emitting element 7;

[0150] Figure 88 is a graph showing the luminance-current efficiency characteristics of light-emitting element 7;

[0151] Figure 89 is a diagram showing the voltage-current characteristics of the light emitting element 7;

[0152] Figure 90 is a diagram showing the luminance-chromaticity coordinate characteristics of the light-emitting element 7;

[0153] Figure 91 is a graph showing the brightness-power efficiency characteristics of the light-emitting element 7;

[0154] Figure 92 is a diagram showing the emission spectrum of light-emitting element 7;

[0155] Figure 93 4 is a diagram showing the time-normalized luminance characteristics of the light emitting element 4;

[0156] Figure 94 is a diagram showing the time-voltage characteristics of the light emitting element 4;

[0157] Figure 95 is a diagram showing time-normalized luminance characteristics of light emitting element 5;

[0158] Figure 96 is a diagram showing the time-voltage characteristics of the light emitting element 5;

[0159] Figure 97 is a graph showing the LC-MS measurement results of 4,6mPnP2Pm;

[0160] Figures 98A to 98D 4,6mPnP2Pm is a graph showing the ToF-SIMS measurement results;

[0161] Figure 99 is a graph showing the LC-MS measurement results of 2Ph-4,6mNP2Pm;

[0162] Figure 100 is a graph showing the LC-MS measurement results of 4,6mTpP2Pm;

[0163] Figure 101 is a graph showing the LC-MS measurement results of 4,6mDBTP2Pm-II;

[0164] Figures 102A to 102D is a graph showing the ToF-SIMS measurement results of 4,6mDBTP2Pm-II;

[0165] Figure 103 is a graph showing the LC-MS measurement results of 2,5mDBTP2Pm-II;

[0166] Figure 104 is a graph showing the LC-MS measurement results of 4,6mDBTP2Pm-III;

[0167] Figure 105 is a graph showing the LC-MS measurement results of 4,6mDBFP2Pm-II;

[0168] Figure 106 is a graph showing the LC-MS measurement results of 2,4mDBFP2Pm-II;

[0169] Figure 107 It is a graph showing the LC-MS measurement results of 2,5mDBFP2Pm-II. DETAILED DESCRIPTION

[0170] The following describes embodiments of the present invention in detail with reference to the accompanying drawings. However, the present invention is not limited to the following description, and those skilled in the art will readily appreciate that the embodiments and details can be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the embodiments described below.

[0171] Implementation Method 1

[0172] In this embodiment, referring to Figure 1 A light-emitting element including a phosphorescent iridium metal complex as a first compound and an organic compound including a pyrimidine skeleton as a second compound will be described.

[0173] In the light-emitting element described in this embodiment, Figure 1As shown, an EL layer 102 including a light-emitting layer 113 is sandwiched between a pair of electrodes (a first electrode 101 and a second electrode 103). The EL layer 102 includes, in addition to the light-emitting layer 113, a hole-injection layer 111, a hole-transport layer 112, an electron-transport layer 114, an electron-injection layer 115, a charge-generation layer 116, and the like. Note that in the description of this embodiment, the first electrode 101 serves as an anode, and the second electrode 103 serves as a cathode. The first electrode 101 is provided on a substrate 100, and a glass substrate or the like can be used as the substrate 100.

[0174] When voltage is applied to this light-emitting element, holes injected from the first electrode 101 and electrons injected from the second electrode 103 recombine in the light-emitting layer 113, causing the phosphorescent iridium metal complex of the first compound to enter an excited state. Then, when the excited phosphorescent iridium metal complex of the first compound returns to a ground state, light is emitted. Thus, in one embodiment of the present invention, the phosphorescent iridium metal complex of the first compound serves as a light-emitting substance in a light-emitting element.

[0175] The hole-injection layer 111 in the EL layer 102 contains a substance with a high hole-transporting property and an acceptor substance. The acceptor substance extracts electrons from the substance with a high hole-transporting property, thereby generating holes. Consequently, holes are injected from the hole-injection layer 111 through the hole-transport layer 112 into the light-emitting layer 113.

[0176] The charge generation layer 116 includes a substance with a high hole-transporting property and an acceptor substance. The acceptor substance extracts electrons from the substance with a high hole-transporting property. The extracted electrons are then injected from the electron injection layer 115, which has an electron-injecting property, through the electron transport layer 114 into the light-emitting layer 113.

[0177] Next, a specific example of manufacturing the light-emitting element described in this embodiment mode will be described.

[0178] The first electrode 101 and the second electrode 103 can be made of metals, alloys, conductive compounds, and mixtures thereof. Specifically, in addition to indium oxide-tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide (IZN), indium oxide containing tungsten oxide and zinc oxide, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), and titanium (Ti), elements belonging to Group 1 or Group 2 of the periodic table, i.e., alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as calcium (Ca) and strontium (Sr), magnesium (Mg), alloys containing these (MgAg, AlLi), rare earth metals such as europium (Eu) and ytterbium (Yb), alloys containing these, and graphene can also be used. In addition, the first electrode 101 and the second electrode 103 can be formed by a sputtering method, an evaporation method (including a vacuum evaporation method), or the like.

[0179] Examples of substances with high hole-transport properties used in the hole injection layer 111, the hole transport layer 112, and the charge generation layer 116 include 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (abbreviated as TPD), 4,4′,4″-tris(carbazol-9-yl)triphenylamine (abbreviated as TCTA), and 4,4′-bis(1,1′-diphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine. ,4″-tris(N,N-diphenylamino)triphenylamine (abbreviated as: TDATA), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as: MTDATA), 4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviated as: BSPB) and other aromatic amine compounds; 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzPCA1), 3, 6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), etc. In addition to the above, 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(10 -phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviated as: CzPA) and other carbazole compounds; 1,3,5-tris (dibenzothiophene-4-yl)-benzene (abbreviated as: DBT3P-II) and other dibenzothiophene compounds; 1,3,5-tris (dibenzofuran-4-yl)benzene (abbreviated as: DBF3P-II) and other dibenzofuran compounds; 9-[3,5-di-(phenanthrene-9-yl)-phenyl]-phenanthrene (abbreviated as: Pn3P) and other condensed ring compounds. These substances are mainly 10 -6 cm 2 Note that substances other than the above materials can also be used as long as the hole-transporting property of the substance is higher than the electron-transporting property.

[0180] Furthermore, high molecular weight compounds such as poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-ethylenetriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N′-[4-(4-diphenylamino)phenyl]phenyl-N′-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), and poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (abbreviated as Poly-TPD) can also be used.

[0181] Alternatively, the hole injection layer 111 and the charge generation layer 116 may contain a material having a high hole transport property and an acceptor material. This is preferred because carrier injection is improved. Examples of acceptor materials for the hole injection layer 111 and the charge generation layer 116 include transition metal oxides or oxides of metals belonging to Groups 4 to 8 of the periodic table. Specifically, molybdenum oxide is particularly preferred.

[0182] The light-emitting layer 113 contains a phosphorescent iridium metal complex of a first compound as a guest material serving as a light-emitting substance, and contains a substance having a triplet excitation energy higher than that of the phosphorescent iridium metal complex of the first compound as a host material.

[0183] Here, a phosphorescent iridium metal complex having a LUMO level of -3.5 eV to -2.5 eV is used as the first compound as the guest material, and an organic compound containing a pyrimidine skeleton is used as the second compound as the host material.

[0184] Since the LUMO energy level of the organic compound containing a pyrimidine skeleton is affected by the pyrimidine skeleton (the LUMO orbital exists near the pyrimidine skeleton), the LUMO energy level of the compound is located at about -3.0 eV. Thus, by using the above-mentioned compound as a combination of the first organic compound and the second organic compound, carriers (electrons) are effectively transferred from the host material to the guest material, whereby the guest material is easy to effectively emit light, and the service life is also improved. At the same time, the guest material is not easy to capture electrons, so it does not hinder the good electron transport properties of the pyrimidine skeleton derived from the host material, and the low voltage of the element can be achieved. In addition, from this point of view, the LUMO energy level of the host material is also preferably above -3.5 eV and below -2.5 eV.

[0185] In addition, the organic compound containing a pyrimidine skeleton of the second compound preferably contains at least one of a benzene skeleton, a biphenyl skeleton, a naphthalene skeleton, a carbazole skeleton, a phenanthrene skeleton, a triphenylene skeleton, a dibenzothiophene skeleton, and a dibenzofuran skeleton as a substituent. By adopting this structure, the LUMO energy level of the second compound is greatly affected by the pyrimidine skeleton (the LUMO orbital exists near the pyrimidine skeleton), so the above effect becomes more significant.

[0186] In particular, when the organic compound containing a pyrimidine skeleton of the second compound contains a carbazole skeleton, holes can be easily transferred, thereby obtaining bipolarity, so it is preferred. When the organic compound containing a pyrimidine skeleton of the second compound contains a condensed ring such as a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton, the carrier transport property is improved, so it is preferred. When the organic compound containing a pyrimidine skeleton of the second compound contains a dibenzothiophene skeleton or a dibenzofuran skeleton, a stereostructure and stable film properties can be obtained, so it is preferred (especially, the 4-substituted products of these dibenzothiophene skeletons and dibenzofuran skeletons have electrochemical stability, so they are preferred).

[0187] In other words, the second compound is an organic compound represented by the general formula (G1).

[0188]

[0189] In the general formula (G1), R 1 and R 2 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 As a substituent, at least one of a naphthalene skeleton, a phenanthrene skeleton, and a triphenylene skeleton is included. 2 At least one of hydrogen, a naphthalene skeleton, a phenanthrene skeleton, and a triphenylene skeleton is contained as a substituent.

[0190] Here, when Ar 1 with Ar 2 When the substituents are the same, the synthesis is easy and therefore preferred. 1 with Ar 2 Different substituents are preferred because a more three-dimensional structure can be obtained.

[0191] The second compound represented by the general formula (G1) more preferably has a structure represented by the general formula (G2). The compound represented by the general formula (G2) is a novel compound suitable for the second compound and is one embodiment of the present invention.

[0192]

[0193] In the general formula (G2), R 1 to R 5 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 4represents any one of hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 5 represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 and α 4 Each of j and k independently represents a substituted or unsubstituted phenylene group.

[0194] Specifically, the second compound represented by the above general formulas (G1) and (G2) more preferably has a structure represented by the general formula (G2-1). In addition, the compound represented by the general formula (G2-1) is a novel compound suitable for the second compound and is one embodiment of the present invention.

[0195]

[0196] In the general formula (G2-1), R 1 to R 8 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 4 、Ar 6 and Ar 7 Each independently represents hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 3 , α 4 , α 6 and α 7 Each of j, k, m and n independently represents 0 or 1.

[0197] Specifically, the second compound represented by the above-mentioned general formulas (G1), (G2) and (G2-1) more preferably has a structure represented by the general formula (G3). In addition, the compound represented by the general formula (G3) is a novel compound suitable for the second compound and is one embodiment of the present invention.

[0198]

[0199] In the general formula (G3), R 1 to R 10Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 3 represents any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group. 7 represents any one of hydrogen, substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted phenanthrenyl and substituted or unsubstituted triphenylene. 3 and α 7 Each of j and n independently represents a substituted or unsubstituted phenylene group.

[0200] When Ar in the above general formulas (G2), (G2-1) and (G3) 1 to Ar 7 When having a substituent, the substituent is selected from any one of an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. When an alkyl group is selected, solubility in an organic solvent is improved, and it is easy to synthesize and form a film using a wet process, so it is preferred. In addition, when a substituted or unsubstituted phenyl group or a substituted or unsubstituted biphenyl group is selected, carrier transport properties are improved, so it is preferred. In addition, when these substituents are included, a more three-dimensional structure can be obtained and the film properties are stable, so it is preferred. However, if the synthesis steps are increased due to these substituents, it is preferably not to have a substituent.

[0201] When R in the above general formulas (G1), (G2-1) and (G3) 1 and R 2 Both sides or R in the general formula (G2) 1 、R 2 and Ar 5 When any two of are hydrogen, the synthesis is easy, so it is preferred. In addition, when hydrogen is selected, the carrier (electron) injection property is improved, and low voltage can be expected, so it is preferred. When R in the above general formulas (G1), (G2-1) and (G3) is 1 and R 2 Both sides or R in the general formula (G2) 1 、R 2 and Ar 5 It is preferred that any two of them are independently an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group, because the amorphous property is improved and the film properties are stabilized.

[0202] In the above general formulas (G2), (G2-1) and (G3), the aryl group (Ar 3 to Ar 7) is bonded to the 4-position or 6-position of pyrimidine through the benzene skeleton. This is to prevent the conjugation from extending from the pyrimidine skeleton to the aromatic group. Furthermore, because these aromatic groups are bonded to the meta position of the benzene skeleton, the conjugation is less likely to extend and the HOMO energy level becomes deeper. Therefore, the band gap (Bg) between the HOMO energy level and the LUMO energy level is likely to become wider, so the S1 energy level and the T1 energy level are likely to increase. Therefore, the compound can be used as a host material for dopants that emit light of shorter wavelengths, and its scope of use as a host material is expanded, so it is preferred. More specifically, the compound is suitable for the host material of materials that emit phosphorescence in the visible light region (blue to red) or materials that emit fluorescence in the visible light region (blue to red). In addition, the HOMO energy level of the compound is deep, so it is suitable for the host material of a luminescent material with a deep HOMO energy level.

[0203] As Ar in the general formulas (G1), (G2), (G2-1) and (G3) 1 to Ar 7 Specific structures of include, for example, substituents represented by structural formula (Ar-1) to structural formula (Ar-5).

[0204]

[0205] In addition, as α in the general formulas (G2), (G2-1) and (G3), 3 , α 4 , α 6 and α 7 Specific structures of include, for example, substituents represented by structural formula (α-1) to structural formula (α-3).

[0206]

[0207] When a substituent is bonded to the para position as in structural formula (α-1), carrier transport properties are improved, which is preferred. When a substituent is bonded to the meta or ortho position as in structural formula (α-2) or structural formula (α-3), the T1 energy level or S1 energy level is improved, which is preferred.

[0208] Specific examples of the second compound represented by the general formulae (G1), (G2), (G2-1), and (G3) include organic compounds represented by the following structural formulae: (100) to (107); (110) to (123); (130) to (135); (140) to (145); (150) to (161); and (300) to (321). Specific examples of the second compound represented by the general formula (G2) include organic compounds represented by the following structural formulae: (306) to (309); (318); and (320). Specific examples of the second compound represented by the general formulae (G2-1) and (G3) include organic compounds represented by the following structural formulae: Structural Formulae (300) to (305); Structural Formulae (310) to (317); Structural Formula (319); and Structural Formula (321). Note that the present invention is not limited to these compounds.

[0209]

[0210]

[0211]

[0212]

[0213]

[0214]

[0215]

[0216]

[0217]

[0218]

[0219]

[0220]

[0221] In addition, various reactions can be applied as the synthesis method of the second compound. For example, the second compound represented by the general formula (G1) can be synthesized by performing the synthesis reaction described below. In addition, the synthesis method of the second compound is not limited to the following synthesis method.

[0222] <<Method for synthesizing the second compound represented by general formula (G1)>>

[0223] First, Synthesis Scheme (A-1) is shown below. As shown in Synthesis Scheme (A-1), a halogenated pyrimidine organic compound (a3) can be synthesized by coupling a dihalogenated pyrimidine organic compound (a1) with an arylboron organic compound (a2).

[0224]

[0225] In addition, in the synthesis scheme (A-1), X 1 and X 2 represents hydrogen or halogen. Note that when X 1 and X 2 When halogen is represented, from the viewpoint of high reactivity, X 1 and X 2 Preferably, it represents bromine, more preferably, it represents iodine. 1 represents boric acid or dialkoxyboron. 1 and R 2 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 As a substituent, at least any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group is contained.

[0226] In addition, various reaction conditions can be used for the coupling reaction in Synthesis Scheme (A-1). As one example, a synthesis method using a metal catalyst in the presence of a base can be used.

[0227] The following is an example of using the Suzuki-Miyaura reaction in Synthesis Scheme (A-1). A palladium catalyst can be used as a metal catalyst, and a mixture of a palladium complex and its ligand can be used as a palladium catalyst. Examples of palladium complexes include palladium(II) acetate, tetrakis(triphenylphosphine)palladium(0), and bis(triphenylphosphine)palladium(II) dichloride. Examples of ligands include tri(o-tolyl)phosphine, triphenylphosphine, and tricyclohexylphosphine. Examples of substances that can be used as a base include organic bases such as sodium tert-butoxide and inorganic bases such as sodium carbonate or potassium carbonate. The reaction is preferably carried out in a solution. Examples of solvents that can be used include: a mixed solvent of acetonitrile and water; a mixed solvent of a diluent such as toluene or xylene and water; a mixed solvent of an alcohol such as toluene or xylene, ethanol, and water; a mixed solvent of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and water; and a mixed solvent of an ether such as ethylene glycol dimethyl ether and water. However, operable catalyst, ligand, alkali, solvent are not limited to these. In addition, in synthesis scheme (A-1), aryl aluminum compound, aryl zirconium compound, aryl zinc compound or aryl tin compound etc. can be used to replace arylboron compound (a2). In addition, the reaction is preferably carried out under an inert atmosphere such as nitrogen, argon gas. In addition, electromagnetic wave can also be utilized to heat.

[0228] Next, as shown in the following synthesis scheme (A-2), the second compound represented by the general formula (G1) can be synthesized by coupling the halogenated pyrimidine organic compound (a3) with the arylboron organic compound (a4).

[0229]

[0230] In addition, X 2 represents hydrogen or halogen. Note that when X 2 When halogen is represented, from the viewpoint of high reactivity, X 2 Preferably, it represents bromine, more preferably, it represents iodine. 2 represents boric acid or dialkoxyboron. 1 and R 2 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 As a substituent, at least any one of a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, and a substituted or unsubstituted triphenylene group is contained.

[0231] In addition, various reaction conditions can be used for the coupling reaction in Synthesis Scheme (A-2). As one example, a synthesis method using a metal catalyst in the presence of a base can be used.

[0232] In the synthesis scheme (A-2), the Suzuki-Miyaura reaction can be used. The details can be synthesized by referring to the above synthesis scheme (A-1).

[0233] In addition, when Ar 1 with Ar 2 If the reaction is the same, the reactions of the above-mentioned synthesis schemes (A-1) and (A-2) can be carried out simultaneously. In other words, (a2) and (a4) can be added to the organic compound (a1) to react simultaneously, which is convenient for synthesis and therefore preferred.

[0234] The second compound according to one embodiment of the present invention can be synthesized through the above steps.

[0235] When the light-emitting layer 113 contains the second compound (host material) and the first compound (guest material), phosphorescence with high luminous efficiency can be obtained from the light-emitting layer 113 .

[0236] Specific examples of the first compound include phosphorescent iridium metal complexes represented by the following structural formulae: Structural Formulas (200) to (206); Structural Formulas (210) to (213); Structural Formulas (220) to (222); Structural Formula (230); Structural Formula (231); and Structural Formula (240). Note that the present invention is not limited to these compounds.

[0237] Structural formulas (200) to (206) represent phosphorescent iridium metal complexes having a pyrimidine skeleton; structural formulas (210) to (213) represent phosphorescent iridium metal complexes having a pyrazine skeleton; structural formulas (220) to (222) represent phosphorescent iridium metal complexes having a pyridine skeleton or a quinoline skeleton; structural formulas (230) and (231) represent phosphorescent iridium metal complexes having a quinoxaline skeleton, and structural formula (240) represents a phosphorescent iridium metal complex having a triazine skeleton.

[0238]

[0239]

[0240]

[0241] The structure of the phosphorescent iridium metal complex is not limited to the one described above. Since the organic compound containing a pyrimidine skeleton as the second compound has a high T1 energy level, it can be used as a host material for a phosphorescent light-emitting material that emits blue-green light or light with a wavelength longer than blue-green. Note that, as described above, the LUMO energy level of the phosphorescent iridium metal complex is preferably between -3.5 eV and -2.5 eV.

[0242] In addition, the HOMO energy level of the phosphorescent iridium metal complex is preferably above -6.0 eV and below -5.0 eV. By adopting the above structure, the phosphorescent iridium metal complex easily captures holes, so the change in the hole mobility of the light-emitting element over time is suppressed. As a result, it is possible to expect a long service life of the element. In particular, when the organic compound containing a pyrimidine skeleton of the second compound contains at least one of a benzene skeleton, a biphenyl skeleton, a naphthalene skeleton, a phenanthrene skeleton, a triphenylene skeleton, a dibenzothiophene skeleton and a dibenzofuran skeleton as a substituent, the HOMO energy level of the organic compound containing a pyrimidine skeleton of the second compound is below -6.0 eV, so the effect of the above-mentioned hole capture becomes more obvious.

[0243] Here, in another embodiment of the present invention, it is preferred that the host material has a pyrimidine skeleton and the guest material has a diazine skeleton. In addition, it is more preferred that both the host material and the guest material have a pyrimidine skeleton. When the above materials are used, the LUMO energy levels of these materials are similar. As a result, carriers (electrons) are effectively transferred from the host material to the guest material, whereby the guest material is easy to effectively emit light, and the service life is also improved. In addition, when the LUMO energy levels of these materials are similar, the guest material is not easy to capture electrons, so it does not hinder the good electron transport properties of the pyrimidine skeleton derived from the host material, and the low voltage of the element can be achieved. Thus, it can be expected that the light-emitting element will have high efficiency, long service life and low driving voltage. When both the host material and the guest material have a pyrimidine skeleton, the interaction between the host molecule and the guest molecule becomes stronger, so the above effect becomes more obvious.

[0244] In addition, the reason why the host material and the guest material can be selected to have LUMO energy levels close to each other is as follows. First, the LUMO energy level of the host material is affected by the pyrimidine skeleton, one of the diazine skeletons that is easily reduced. In particular, the LUMO orbital of the host material represented by the general formula (G1), (G2), (G2-1) and (G3) exists near the pyrimidine skeleton. On the other hand, the guest material also has a diazine skeleton that is easily reduced, so the LUMO energy level of the guest material is also affected by the diazine skeleton. In particular, when the diazine skeleton forms a coordination bond with iridium, the LUMO orbital does not exist in the central metal but exists in the diazine skeleton. Therefore, both the host material and the guest material have LUMO orbitals derived from the diazine skeleton, so the LUMO energy levels of these materials are also close.

[0245] In addition, when the phosphorescent iridium metal complex (first compound) has a diazine skeleton, particularly a pyrimidine skeleton, as described above, the LUMO energy level of the phosphorescent iridium metal complex is preferably from -3.5 eV to -2.5 eV. In addition, its HOMO energy level is preferably from -6.0 eV to -5.0 eV. In this case, preferred examples of the host material (second compound) are those listed above.

[0246] As described above, the LUMO orbital of the second compound (host material) of one embodiment of the present invention is located near the pyrimidine backbone, which is easily reduced and has good electron-transporting properties. Therefore, the second compound of one embodiment of the present invention has high electron-transporting properties and reduces the driving voltage of the device.

[0247] In addition, while Embodiment 1 describes a phosphorescent light-emitting element using a phosphorescent iridium metal complex as the first compound, this structure is not limited thereto. The organic compound containing a pyrimidine skeleton as the second compound has a high T1 energy level and therefore also a high S1 energy level. Therefore, the organic compound containing a pyrimidine skeleton as the second compound can also be used as a host material for a material that emits fluorescence in the visible light region.

[0248] In addition, a variety of substances (host materials) for dispersing the light-emitting substance (guest material) can be used. Therefore, in addition to the organic compound containing a pyrimidine skeleton as the second compound, the light-emitting layer may further contain a second host material.

[0249] Examples of the second host material include the material used for the hole-transport layer 112 .

[0250] The electron-transport layer 114 is a layer containing a substance with a high electron-transport property. As the electron-transport layer 114, a metal complex such as Alq3, tris(4-methyl-8-hydroxyquinolinolato)aluminum (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinolinolato)beryllium (abbreviated as BeBq2), BAlq, Zn(BOX)2, or bis[2-(2-hydroxyphenyl)benzothiazole]zinc (abbreviated as Zn(BTZ)2) can be used. In addition, heteroaromatic compounds such as 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviation: OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: BPhen), bathocuproine (abbreviation: BCP), 4,4′-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs), etc. can also be used. In addition, high molecular weight compounds such as poly (2,5-pyridinediyl) (abbreviated as PPy), poly [(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py), and poly [(9,9-dioctylfluorene-2,7-diyl)-co-(2,2′-bipyridine-6,6′-diyl)] (abbreviated as PF-BPy) can also be used. The substances described here are mainly polymers with an electron mobility of 10 -6 cm 2 In addition, as long as the electron-transporting property is higher than the hole-transporting property, a substance other than the above substances may be used for the electron-transporting layer.

[0251] Furthermore, the organic compound containing a pyrimidine skeleton, which is the second compound used in the present invention, is also a material having excellent electron-transporting properties, and therefore this compound is suitable for use in an electron-transporting layer.

[0252] Note that the electron-transport layer 114 may be formed not only as a single layer but also as a stack of two or more layers composed of the above-mentioned substances.

[0253] The electron injection layer 115 is a layer containing a substance with high electron injection properties. As the electron injection layer 115, alkali metals, alkaline earth metals, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), and lithium oxide (LiO x ) or their compounds. In addition, rare earth metal compounds such as erbium fluoride (ErF 3 ) can be used. In addition, the substances constituting the electron-transporting layer 114 described above can also be used.

[0254] Alternatively, a composite material formed by mixing an organic compound with an electron donor (donor) can also be used for the electron injection layer 115. Because the electron donor in this composite material generates electrons in the organic compound, the electron injection and electron transport properties are high. In this case, the organic compound is preferably a material that can efficiently transport the generated electrons. Specifically, for example, the substances constituting the electron transport layer 114 as described above (metal complexes or heteroaromatic compounds, etc.) can be used. As an electron donor, it is sufficient to use a substance that exhibits electron donor properties to the organic compound. Specifically, alkali metals, alkaline earth metals and rare earth metals are preferably used, and lithium, cesium, magnesium, calcium, erbium, ytterbium, etc. can be mentioned. In addition, alkali metal oxides or alkaline earth metal oxides are preferably used, for example, lithium oxide, calcium oxide, barium oxide, etc. can be mentioned. In addition, Lewis bases such as magnesium oxide can be used. Alternatively, organic compounds such as tetrathiafulvalene (abbreviated as: TTF) can also be used.

[0255] In addition, the hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, electron injection layer 115 and charge generation layer 116 can be formed by evaporation (including vacuum evaporation), inkjet, coating and the like.

[0256] In the above-described light-emitting element, a current is generated due to a potential difference between the first electrode 101 and the second electrode 103, and holes and electrons recombine in the EL layer 102 to emit light. This light is then extracted to the outside through one or both of the first electrode 101 and the second electrode 103. Therefore, one or both of the first electrode 101 and the second electrode 103 are light-transmitting electrodes.

[0257] Since the light-emitting element described above can obtain phosphorescence derived from the phosphorescent iridium metal complex of the first compound, a light-emitting element with higher efficiency than a light-emitting element using a fluorescent compound can be realized.

[0258] The light-emitting element described in this embodiment is an example of a light-emitting element structure. Light-emitting elements having structures described in other embodiments can also be used in a light-emitting device according to an embodiment of the present invention. Furthermore, as a light-emitting device including such a light-emitting element, a passive matrix light-emitting device or an active matrix light-emitting device can be manufactured. Furthermore, a light-emitting device having a microcavity structure different from the light-emitting elements described in other embodiments can also be manufactured. All of these light-emitting devices are encompassed by the present invention.

[0259] In the case of an active-matrix light-emitting device, there are no particular restrictions on the TFT structure. For example, staggered TFTs or inversely staggered TFTs can be used as appropriate. Furthermore, the driver circuit formed on the TFT substrate can be formed by either or both N-type and P-type TFTs. Furthermore, there are no particular restrictions on the crystallinity of the semiconductor film used for the TFT. For example, amorphous semiconductor films, crystalline semiconductor films, and oxide semiconductor films can be used.

[0260] Note that the structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0261] Implementation Method 2

[0262] In this embodiment, an organic compound including a pyrimidine skeleton is described.

[0263] One embodiment of the present invention is an organic compound represented by the general formula (G4).

[0264]

[0265] In the general formula (G4), Ar 11 、Ar 12 、R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13 and Ar 14 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 , α 2 , α 8 and α 9 Each of h, i, x and y independently represents 0 or 1. 1 and E 2 Each independently represents sulfur or oxygen.

[0266] Another embodiment of the present invention is an organic compound represented by the general formula (G5).

[0267]

[0268] In the general formula (G5), Ar 11 、Ar 12 、R 11 to R13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13 and Ar 14 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0269] Another embodiment of the present invention is an organic compound represented by the general formula (G6).

[0270]

[0271] In the general formula (G6), R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0272] Another embodiment of the present invention is an organic compound represented by the general formula (G7).

[0273]

[0274] In the general formula (G7), R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 and E 2 Each independently represents sulfur or oxygen.

[0275] Another embodiment of the present invention is an organic compound represented by structural formula (400).

[0276]

[0277] In addition, as Ar in the general formula (G4) and the general formula (G5), 13 and Ar 14Specific structures of include, for example, substituents represented by structural formula (Ar-6) to structural formula (Ar-11).

[0278]

[0279] In addition, as α in the general formula (G4) 1 , α 2 , α 8 and α 9 Specific structures of include, for example, substituents represented by structural formula (α-4) to structural formula (α-6).

[0280]

[0281] When a substituent is bonded to the para position as in structural formula (α-4), carrier transport properties are improved, which is preferred. When a substituent is bonded to the meta or ortho position as in structural formula (α-5) or structural formula (α-6), the T1 energy level or S1 energy level is improved, which is preferred.

[0282] In addition, in Ar 13 and Ar 14 When there is a substituent, the substituent is independently selected from any one of an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 1 , α 2 , α 8 and α 9 In the case of having a substituent, the substituent is independently selected from any one of an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophene-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. In addition, in general formulas (G4) to (G6), a phenylene group is bonded to any one or two of the 2nd, 4th, 5th, and 6th positions of the pyrimidine ring. In addition, in general formulas (G4) to (G7), an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group may also be bonded to any one or more of the 2nd, 4th, 5th, and 6th positions of the pyrimidine ring as a substituent. When having these substituents, a more three-dimensional structure and stable film properties can be obtained, so it is preferred. In addition, when having an alkyl group, the solubility in a solvent is improved, and it is easy to synthesize and form a film using a wet method, so it is preferred. However, when considering the synthesis cost, it is sometimes preferred not to have these substituents.

[0283] When Ar in the above general formulas (G4) and (G5) 11 and Ar 12When hydrogen is used, it is easy to synthesize, so it is preferred. In addition, when hydrogen is selected, the carrier (electron) injection property is improved, and low voltage can be expected, so it is preferred. In addition, when Ar 11 and Ar 12 When each of them is independently an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group, the amorphous property is improved and the film properties are stabilized, which is preferred.

[0284] Specific examples of the organic compound represented by general formula (G4) include organic compounds represented by structural formulas (400) to (415) and structural formulas (430) to (440). Note that the present invention is not limited to these compounds.

[0285]

[0286]

[0287]

[0288]

[0289]

[0290] As a synthetic method of an organic compound of one embodiment of the present invention, various reactions can be applied. For example, an organic compound of one embodiment of the present invention represented by general formula (G4) can be synthesized by performing the synthetic reaction described below. In addition, an organic compound of one embodiment of the present invention is not limited to the following synthetic method.

[0291] 《Method for synthesizing an organic compound represented by general formula (G4)》

[0292] First, a synthesis scheme (B-1) is shown below.

[0293]

[0294] As shown in Synthesis Scheme (B-1), the halogenated pyrimidine compound (b3) can be synthesized by coupling the dihalogenated pyrimidine compound (b1) with the arylboron compound (b2).

[0295] In the synthesis scheme (B-1), R 11 to R 13 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 and α 8 Each independently represents a substituted or unsubstituted phenylene group. In addition, h and x each independently represent 0 or 1. In addition, E 1 represents sulfur or oxygen. 3 and X 4 Each independently represents hydrogen, chlorine, bromine or iodine. 13 When X represents hydrogen, 4 In addition, from the viewpoint of high reactivity, X 3 and X 4 Preferably, it represents bromine, more preferably, it represents iodine. 3 represents boric acid or dialkoxyborane.

[0296] In addition, various reaction conditions can be used for the coupling reaction in Synthesis Scheme (B-1). As one example, a synthesis method using a metal catalyst in the presence of a base can be used.

[0297] The following is an example of using the Suzuki-Miyaura reaction in Synthesis Scheme (B-1). A palladium catalyst can be used as a metal catalyst, and a mixture of a palladium complex and its ligand can be used as a palladium catalyst. Examples of palladium complexes include palladium(II) acetate, tetrakis(triphenylphosphine)palladium(0), and bis(triphenylphosphine)palladium(II) dichloride. Examples of ligands include tri(o-tolyl)phosphine, triphenylphosphine, and tricyclohexylphosphine. Examples of substances that can be used as a base include organic bases such as sodium tert-butoxide and inorganic bases such as sodium carbonate or potassium carbonate. The reaction is preferably carried out in a solution. Examples of solvents that can be used include: a mixed solvent of acetonitrile and water; a mixed solvent of a diluent such as toluene or xylene and water; a mixed solvent of an alcohol such as toluene or xylene, ethanol, and water; a mixed solvent of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and water; and a mixed solvent of an ether such as ethylene glycol dimethyl ether and water. However, the catalyst, base, and solvent that can be used are not limited to these.

[0298] In addition, in the synthesis scheme (B-1), an aryl aluminum compound, an aryl zirconium compound, an aryl zinc compound or an aryl tin compound can be used instead of the arylboron compound (b2). In addition, the reaction is preferably carried out under an inert atmosphere such as nitrogen or argon. In addition, electromagnetic waves can also be used for heating.

[0299] Next, as shown in Synthesis Scheme (B-2), the organic compound represented by the general formula (G4) shown in this embodiment can be synthesized by coupling the halogenated pyrimidine compound (b3) with the arylboron compound (b4).

[0300]

[0301] In the synthesis scheme (B-2), Ar 11 、Ar 12 、R 11 to R 13 and R 21 to R 23 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, and a substituted or unsubstituted biphenyl group. 13 and Ar 14 Each independently represents any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted dibenzothiophen-4-yl group, and a substituted or unsubstituted dibenzofuran-4-yl group. 1 , α 2 , α 8 and α 9 Each of h, i, x and y independently represents 0 or 1. 1 and E 2 Each independently represents sulfur or oxygen. 3 represents hydrogen, chlorine, bromine or iodine. Note that when Ar 13 When X represents hydrogen, 3 In addition, from the viewpoint of high reactivity, X 3 Preferably, it represents bromine, more preferably, it represents iodine. 4 represents boric acid or dialkoxyborane.

[0302] In addition, various reaction conditions can be used for the coupling reaction in Synthesis Scheme (B-2). As one example, a synthesis method using a metal catalyst in the presence of a base can be used.

[0303] In the synthesis scheme (B-2), the Suzuki-Miyaura reaction can be used. Detailed information can be found in the above synthesis scheme (B-1), so it is omitted here.

[0304] In addition, when the aryl moiety of compound (b2) is the same as that of compound (b4), the reactions of the above-mentioned synthesis schemes (B-1) and (B-2) can be carried out simultaneously (in other words, compound (b2) and compound (b4) can be added to the organic compound (b1) to react together, which is convenient for synthesis and is therefore preferred.

[0305] The organic compound of this embodiment can be synthesized through the above steps.

[0306] Since the organic compound of this embodiment has a high S1 energy level, a high T1 energy level, and an energy gap (Eg) between a wide HOMO energy level and a LUMO energy level, high current efficiency can be obtained by using the organic compound of this embodiment as a host material for dispersing the light-emitting substance in the light-emitting layer in a light-emitting element. In particular, the organic compound of this embodiment is suitable for use as a host material for dispersing phosphorescent compounds. In addition, since the organic compound of this embodiment is a substance with high electron transport properties, it can be applied to the material of the electron transport layer in the light-emitting element. By using the organic compound of this embodiment, a light-emitting element with low driving voltage and high current efficiency can be realized. In addition, by using this light-emitting element, a light-emitting device, an electronic device, and a lighting device with low power consumption can be obtained.

[0307] Implementation 3

[0308] In this embodiment, referring to Figure 2A and Figure 2B A light-emitting element in which the organic compound described in Embodiment 2 is used for a light-emitting layer will be described.

[0309] In this embodiment, referring to Figure 2A and Figure 2B A light-emitting element including 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II) represented by structural formula (400), which is an example of the organic compound described in Embodiment 2, is described.

[0310] In the light-emitting element of this embodiment, an EL layer having at least a light-emitting layer is inserted between a pair of electrodes. The EL layer may have a plurality of layers in addition to the light-emitting layer. The plurality of layers are stacked in the form of a combination of layers formed of materials having high carrier injection properties and materials having high carrier transport properties, so that a light-emitting region is formed away from the electrodes, that is, carriers recombine in a portion away from the electrodes. In this specification, a layer containing a material having high carrier injection properties or having high carrier transport properties is referred to as a functional layer, and the functional layer has a function such as injection or transport of carriers. As the functional layer, a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, etc. can be used.

[0311] exist Figure 2A In the light-emitting element of this embodiment shown, the EL layer 1020 includes a light-emitting layer 1130, and the EL layer 1020 is between a pair of electrodes, namely, a first electrode 1010 and a second electrode 1030. The EL layer 1020 includes a hole-injection layer 1110, a hole-transport layer 1120, a light-emitting layer 1130, an electron-transport layer 1140, and an electron-injection layer 1150. Figure 2A The light-emitting element shown includes a first electrode 1010 formed on a substrate 1000; a hole-injection layer 1110, a hole-transport layer 1120, a light-emitting layer 1130, an electron-transport layer 1140, and an electron-injection layer 1150 formed in this order on the first electrode 1010; and a second electrode 1030 formed on the electron-injection layer 1150. Note that in the light-emitting element described in this embodiment, the first electrode 1010 functions as an anode, and the second electrode 1030 functions as a cathode.

[0312] The substrate 1000 serves as a support for the light-emitting element. For example, glass, quartz, plastic, or the like can be used as the substrate 1000. Alternatively, a flexible substrate can be used. A flexible substrate is a bendable substrate, such as a plastic substrate made of polycarbonate, polyarylate, or polyethersulfone. Alternatively, a film (composed of polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, etc.), an inorganic film formed by vapor deposition, or the like can be used. Note that other materials can be used as long as they serve as a support during the manufacturing process of the light-emitting element.

[0313] As the first electrode 1010, it is preferred to use a metal, alloy, conductive compound, or mixture thereof having a high work function (specifically, 4.0 eV or above). Specific examples include: indium tin oxide (ITO), indium tin oxide containing silicon or silicon oxide, indium zinc oxide, indium oxide containing tungsten oxide and zinc oxide (IWZO), etc. These conductive metal oxide films are usually formed by sputtering, but can also be formed by sol-gel methods. For example, indium zinc oxide can be formed by sputtering using a target material obtained by adding 1 wt% to 20 wt% zinc oxide to indium oxide. In addition, indium oxide containing tungsten oxide and zinc oxide (IWZO) can be formed by sputtering using a target material obtained by adding 0.5 wt% to 5 wt% tungsten oxide and 0.1 wt% to 1 wt% zinc oxide to indium oxide. In addition, gold, platinum, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, metal nitride materials (such as titanium nitride), etc. can also be used.

[0314] Note that in the EL layer 1020, when the layer in contact with the first electrode 1010 is formed using a composite material formed using an organic compound and an electron acceptor described below, any of various metals, alloys, conductive compounds, and mixtures thereof can be used to form the first electrode 1010, regardless of the work function. For example, aluminum, silver, or an aluminum-containing alloy (such as Al—Si) can be used.

[0315] The EL layer 1020 formed over the first electrode 1010 includes at least the light-emitting layer 1130. A portion of the EL layer 1020 contains an organic compound, which is one embodiment of the present invention. A known substance, such as a low-molecular-weight compound or a high-molecular-weight compound, can be used for a portion of the EL layer 1020. Note that the material forming the EL layer 1020 may be either a substance composed solely of an organic compound or a substance partially containing an inorganic compound.

[0316] In addition, if Figure 2A As shown, the EL layer 1020 can be formed by appropriately stacking a combination of a hole injection layer 1110 , a hole transport layer 1120 , an electron transport layer 1140 , an electron injection layer 1150 , and the like, and a light-emitting layer 1130 .

[0317] The hole injection layer 1110 is a layer containing a substance having a high hole injection property. Examples of substances having a high hole injection property include metal oxides such as molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, and manganese oxide. Alternatively, a phthalocyanine-based compound such as phthalocyanine (abbreviated as HPc) or copper (II) phthalocyanine (abbreviated as CuPc) can be used.

[0318] Alternatively, the following low molecular weight organic compounds can be used: 4,4′,4″-tris(N,N-diphenylamino)triphenylamine (abbreviated as TDATA), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as MTDATA), 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviated as DPAB), 4,4′-bis(N-{4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviated as D NTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviated as DPA3B), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzPCA2) and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviated as PCzPCN1), etc.

[0319] In addition, a polymer compound (e.g., an oligomer, a dendrimer, or a polymer) can be used. Examples of polymer compounds include poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-vinyltriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N′-[4-(4-diphenylamino)phenyl]phenyl-N′-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), or poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (abbreviated as Poly-TPD). Alternatively, a polymer compound to which an acid is added can be used, for example, poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) or polyaniline / poly(styrenesulfonic acid) (PAni / PSS).

[0320] A composite material formed by mixing an organic compound with an electron acceptor can be used for the hole injection layer 1110. This composite material has excellent hole injection and hole transport properties because holes can be generated in the organic compound by the electron acceptor. In this case, the organic compound is preferably a material that excels in transporting the generated holes (a substance having high hole transport properties).

[0321] As the organic compound for the composite material, various compounds can be used, such as aromatic amine compounds, carbazole compounds, aromatic hydrocarbons and high molecular weight compounds (e.g., oligomers, dendrimers or polymers). The organic compound for the composite material is preferably an organic compound having high hole transport properties. Specifically, it is preferred to use an organic compound with a hole mobility of 10 -6 cm 2 / Vs or more. Note that other substances besides the above substances can be used as long as they are substances with greater hole transport properties than electron transport properties. Specific examples of organic compounds that can be used for the composite material are as follows.

[0322] Examples of organic compounds that can be used in the composite material include aromatic amine compounds such as TDATA, MTDATA, DPAB, DNTPD, DPA3B, PCzPCA1, PCzPCA2, PCzPCN1, 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (abbreviated as TPD) and 4-phenyl-4′-(9-phenylfluorene-9- carbazole compounds such as 4,4′-bis(N-carbazolyl)biphenyl (CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (CzPA), 9-phenyl-3-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (PCzPA), and 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene.

[0323] Alternatively, any one of the following aromatic hydrocarbon compounds can be used: 2-tert-butyl-9,10-bis(2-naphthyl)anthracene (abbreviated as t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-di(3,5-diphenylphenyl)anthracene (abbreviated as DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviated as t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviated as DPPA), : DNA), 9,10-diphenylanthracene (abbreviated as: DPAnth), 2-tert-butylanthracene (abbreviated as: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviated as: DMNA), 9,10-bis[2-(1-naphthyl)phenyl)-2-tert-butylanthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, etc.

[0324] Alternatively, any one of the following aromatic hydrocarbon compounds can be used: 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9′-bianthracene, 10,10′-diphenyl-9,9′-bianthracene, 10,10′-bis(2-phenylphenyl)-9,9′-bianthracene, 10,10′-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9′-bianthracene, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, pentacene, coronene, 4,4′-bis(2,2-diphenylvinyl)biphenyl (abbreviated as: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviated as: DPVPA), etc.

[0325] As electron acceptors, for example, organic compounds such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as: F4-TCNQ) and chloranil and transition metal oxides can be cited. In addition, there are oxides of metals from Groups 4 to 8 of the periodic table. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide and rhenium oxide are preferably used because they have high electron accepting properties. Among them, molybdenum oxide is particularly preferred because it is stable in air and has low hygroscopicity and is easy to handle.

[0326] Note that as the hole-injection layer 1110 , a composite material formed of the above-mentioned polymer compound such as PVK, PVTPA, PTPDMA, or Poly-TPD and the above-mentioned electron acceptor can be used.

[0327] The hole transport layer 1120 is a layer containing a substance having high hole transport properties. As a substance having high hole transport properties, an aromatic amine compound such as NPB, TPD, BPAFLP, 4,4′-bis[N-(9,9-dimethylfluoren-2-yl)-N-phenylamino]biphenyl (abbreviated as DFLDPBi) or 4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviated as BSPB) can be used. The substances described here mainly have a hole mobility of 10 -6 cm 2 / Vs or higher. Note that substances other than the above substances may be used as long as they have a hole-transporting property greater than their electron-transporting property. The layer containing a substance with high hole-transporting properties is not limited to a single layer and may be a stack of two or more layers containing any of the above substances.

[0328] Alternatively, the hole-transport layer 1120 may be made of a carbazole derivative such as CBP, CzPA, or PCzPA, or an anthracene derivative such as t-BuDNA, DNA, or DPAnth.

[0329] Alternatively, as the hole transport layer 1120, a polymer compound such as PVK, PVTPA, PTPDMA, or Poly-TPD can be used.

[0330] The light-emitting layer 1130 is a layer containing a light-emitting substance. Note that this embodiment describes a case where 4,6-bis[3-(dibenzothiophene-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II) described in Embodiment 2 is used for the light-emitting layer. In a light-emitting layer in which a light-emitting substance (guest material) is dispersed in another substance (host material), 4,6mDBTP2Pm-II can be used as a host material. By dispersing a guest material that is a light-emitting substance in 4,6mDBTP2Pm-II, light emission can be obtained from the guest material. As described above, the organic compound of one embodiment of the present invention is suitable for use as a host material in a light-emitting layer.

[0331] Furthermore, the substance (host material) in which the light-emitting substance (guest material) is dispersed can be a plurality of substances. Thus, the light-emitting layer can contain a second host material in addition to 4,6mDBTP2Pm-II.

[0332] Examples of the second host material include the material used for the hole-transport layer 1120 .

[0333] As the light-emitting substance, for example, a fluorescent compound that emits fluorescence or a phosphorescent compound that emits phosphorescence can be used. Fluorescent substances that can be used for the light-emitting layer 1130 are as follows. Examples of materials that emit blue light include: N,N′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphenylstilbene-4,4′-diamine (abbreviated as: YGA2S), 4-(9H-carbazol-9-yl)-4′-(10-phenyl-9-anthryl)triphenylamine (abbreviated as: YGAPA), 4-(10-phenyl-9-anthryl)-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: PCBAPA), etc. In addition, examples of materials that emit green light include: N-(9,10-diphenyl-2-anthracenyl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviated as: 2PCAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthracenyl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviated as: 2PCABPhA), N-(9,10-diphenyl-2-anthracenyl)-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviated as: Examples of yellow-emitting materials include rubrene and 5,12-bis(1,1′-biphenyl-4-yl)-6,11-diphenyltetracene (BPT). In addition, examples of materials that emit red light include: N,N,N′,N′-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviated as: p-mPhTD), 7,14-diphenyl-N,N,N′,N′-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviated as: p-mPhAFD), etc.

[0334] Among the phosphorescent compounds that can be used for the light-emitting layer 1130, for example, a blue light-emitting material can be bis[2-(4′,6′-difluorophenyl)pyridinium-N,C 2 ′]iridium(III)tetrakis(1-pyrazolyl)borate (abbreviated as FIr6), bis[2-(4′,6′-difluorophenyl)pyridinium-N,C 2 ′] iridium (III) picolinate (abbreviated as FIrpic), bis{2-[3′,5′-bis(trifluoromethyl)phenyl]pyridinium-N,C 2′}iridium(III) picolinate (abbreviated as: Ir(CF3ppy)2(pic)), bis[2-(4′,6′-difluorophenyl)pyridinium-N,C 2 '] iridium (III) acetylacetonate (abbreviated as FIr (acac)). In addition, examples of green light-emitting materials include tris (2-phenylpyridinium-N, C 2′ )iridium (III) (abbreviated as: Ir(ppy)3), acetylacetonate bis(2-phenylpyridine-N,C 2′ )iridium(III) (abbreviated as Ir(ppy)2(acac)), acetylacetonate bis(1,2-diphenyl-1H-benzimidazolium)iridium(III) (abbreviated as Ir(pbi)2(acac)), acetylacetonate bis(benzo[h]quinolinate)iridium(III) (abbreviated as Ir(bzq)2(acac)), tris(benzo[h]quinolinate)iridium(III) (abbreviated as Ir(bzq)3), etc. Examples of materials emitting yellow light include acetylacetonate bis(2,4-diphenyl-1,3-oxazol-N,C 2′ )iridium(III) (abbreviated as Ir(dpo)2(acac)), acetylacetonate bis[2-(4′-(pentafluorophenylphenyl)pyridinium(III)] (abbreviated as Ir(p-PF-ph)2(acac)), acetylacetonate bis(2-phenylbenzothiazolyl-N,C 2′ )iridium(III) (abbreviated as Ir(bt)2(acac)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)-5-methylpyrazine]iridium(III) (abbreviated as Ir(Fdppr-Me)2(acac)), (acetylacetonato)bis{2-(4-methoxyphenyl)-3,5-dimethylpyrazine}iridium(III) (abbreviated as Ir(dmmoppr)2(acac)). Examples of materials emitting orange light include tris(2-phenylquinolinato-N,C 2′ )iridium (III) (abbreviated as: Ir(pq)3), acetylacetonate bis(2-phenylquinoline-N,C 2′ )iridium(III) (abbreviated as Ir(pq)2(acac)), (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazine)iridium(III) (abbreviated as Ir(mppr-Me)2(acac)), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazine)iridium(III) (abbreviated as Ir(mppr-iPr)2(acac)), etc. Examples of materials emitting red light include organometallic complexes, for example, acetylacetonatobis[2-(2′-benzo[4,5-α]thienyl)pyridine-N,C 3′ )iridium (III) (abbreviated as: Ir(btp)2(acac)), acetylacetonate bis(1-phenylisoquinoline-N,C 2′) iridium(III) (abbreviated as Ir(piq)2(acac), (acetylacetonato)bis(2,3-bis(4-fluorophenyl)quinoxaline)iridium(III) (abbreviated as Ir(Fdpq)2(acac)), (acetylacetonato)bis[2,3,5-triphenylpyrazine]iridium(III) (abbreviated as Ir(tppr)2(acac)), bis(2,3,5-triphenylpyrazine)(dipivaloylmethane)iridium(III) (abbreviated as Ir(tppr)2(dpm)), and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrinplatinum(II) (abbreviated as PtOEP). In addition , because light emission from rare earth metal ions (electronic transitions between different multiplicities) can be obtained through, for example, the following rare earth metal complexes: tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: Tb(acac)3(Phen)), tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: Eu(DBM)3(Phen)) and tris[1-(2-thiophenoyl)-3,3,3-trifluoroacetonate](monophenanthroline)europium(III) (abbreviation: Eu(TTA)3(Phen)), such rare earth metal complexes can be used as phosphorescent compounds.

[0335] As a luminescent substance, a polymer compound can also be used. Specifically, examples of materials that emit blue light include poly(9,9-dioctylfluorene-2,7-diyl) (abbreviated as PFO), [(9,9-dioctylfluorene-2,7-diyl)-(2,5-dimethoxybenzene-1,4-diyl)] copolymer (abbreviated as PF-DMOP), and {(9,9-dioctylfluorene-2,7-diyl)-[N,N′-di-(p-butylphenyl)-1,4-diaminobenzene]} (abbreviated as TAB-PFH). In addition, examples of materials that emit green light include: poly(p-phenylene vinylene) (abbreviation: PPV), [(9,9-dihexylfluorene-2,7-diyl)-(benzo[2,1,3]thiadiazole-4,7-diyl) alternating copolymer] (abbreviation: PFBT), [(9,9-dioctyl-2,7-divinylenefluorenylene)-(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene) alternating copolymer, etc. In addition, examples of materials that emit orange to red light include: poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene] (abbreviation: MEH-PPV), poly(3-butylthiophene-2,5-diyl) (abbreviation: R4-PAT), {[9,9-dihexyl-2,7-bis(1-cyanovinylene)fluorenyl]-[2,5-bis(N,N′-diphenylamino)-1,4-phenylene]} alternating copolymer, {[2-methoxy-5-(2-ethylhexyloxy)-1,4-bis(1-cyanovinylenephenyl)]-[2,5-bis(N,N′-diphenylamino)-1,4-phenylene]} alternating copolymer (abbreviation: CN-PPV-DPD), etc.

[0336] In addition, the organic compound described in Embodiment 2 and the second compound described in Embodiment 1 also have fluorescence and can be used as a light-emitting material.

[0337] The electron-transport layer 1140 is a layer containing a substance having a high electron-transport property. Examples of substances having a high electron-transport property include metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as tris(8-hydroxyquinoline)aluminum (Alq), tris(4-methyl-8-hydroxyquinoline)aluminum (Almq3), bis(10-hydroxybenzo[h]-quinoline)beryllium (BeBq2), or bis(2-methyl-8-hydroxyquinoline)(4-phenylphenol)aluminum (BAlq). Alternatively, metal complexes containing an azole- or thiazolyl-based ligand, such as bis[2-(2-hydroxyphenyl)benzoxazolyl]zinc (Zn(BOX)2) or bis[2-(2-hydroxyphenyl)benzothiazolyl]zinc (Zn(BTZ)2), can be used. Other compounds besides metal complexes can also be used: 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as OXD-7), 3-(4-biphenyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviated as TAZ), bathophenanthroline (abbreviated as BPhen), bathocuproin (abbreviated as BCP), etc. The substances described here are mainly electron mobility 10 -6 cm 2 In addition, the electron transport layer is not limited to a single layer, and may be a stack of two or more layers containing the substance.

[0338] In addition, the organic compound described in Embodiment 2 and the second compound described in Embodiment 1 also have a pyrimidine skeleton and are therefore suitable for the electron-transport layer 1140 .

[0339] The electron injection layer 1150 is a layer containing a substance having a high electron injection property. For the electron injection layer 1150, an alkali metal, an alkaline earth metal, or a compound thereof, such as lithium, cesium, calcium, lithium fluoride, cesium fluoride, calcium fluoride, or lithium oxide, can be used. Alternatively, a rare earth metal compound such as erbium fluoride can be used. Alternatively, the substances described above for forming the electron transport layer 1140 can also be used.

[0340] Alternatively, a composite material formed by mixing an organic compound with an electron donor can be used for the electron injection layer 1150. This composite material has excellent electron injection properties and electron transport properties because it can generate electrons in the organic compound through the electron donor. In this case, the organic compound is preferably a material with excellent performance in transporting the generated electrons. Specifically, for example, the substances forming the electron transport layer 1140 described above (such as metal complexes and heteroaromatic compounds) can be used. As an electron donor, a substance that shows electron donor properties to the organic compound can be used. Specifically, alkali metals, alkaline earth metals and rare earth metals, such as lithium, cesium, magnesium, calcium, erbium, ytterbium, etc. are preferably used. In addition, alkali metal oxides or alkaline earth metal oxides, such as lithium oxide, calcium oxide, barium oxide, etc. are preferably used. Alternatively, a Lewis base such as magnesium oxide can be used. Alternatively, an organic compound such as tetrathiafulvalene (abbreviated as: TTF) can be used.

[0341] Note that each of the hole injection layer 1110 , hole transport layer 1120 , light-emitting layer 1130 , electron transport layer 1140 , and electron injection layer 1150 can be formed by, for example, evaporation (including vacuum evaporation), inkjet, or coating.

[0342] When the second electrode 1030 serves as a cathode, it is preferably formed using a metal, alloy, conductive compound, or mixture thereof having a low work function (preferably, a work function of 3.8 eV or less). Specifically, the following can be used: aluminum or silver; elements belonging to Group 1 or Group 2 of the periodic table, i.e., alkali metals such as lithium or cesium, or alkaline earth metals such as calcium or strontium; magnesium; alloys of the above metals (e.g., Mg-Ag or Al-Li); rare earth metals such as europium or ytterbium; and alloys of the above metals.

[0343] Note that in the EL layer 1020, when the layer in contact with the second electrode 1030 is formed of a composite material in which the organic compound described above is mixed with an electron donor, various conductive materials such as aluminum, silver, ITO, indium tin oxide containing silicon or silicon oxide can be used without considering the work function.

[0344] Note that the second electrode 1030 can be formed by a vacuum evaporation method or a sputtering method. Alternatively, when silver paste or the like is used, a coating method, an inkjet method, or the like can be used.

[0345] In the above-described light-emitting element, a current is generated due to a potential difference between the first electrode 1010 and the second electrode 1030, and light is emitted due to recombination of holes and electrons in the EL layer 1020. The emitted light is then extracted to the outside through one or both of the first electrode 1010 and the second electrode 1030. Therefore, one or both of the first electrode 1010 and the second electrode 1030 have a property of transmitting visible light.

[0346] In addition, the layer structure between the first electrode 1010 and the second electrode 1030 is not limited to the above structure. A structure different from the above structure can be adopted as long as a light-emitting region where holes and electrons recombine is present in a portion away from the first electrode 1010 and the second electrode 1030 to prevent quenching caused by the light-emitting region being close to the metal.

[0347] That is, there are no particular restrictions on the stacked structure of the layers. Materials with high electron-transporting properties, materials with high hole-transporting properties, materials with high electron-injecting properties, materials with high hole-injecting properties, bipolar materials (materials with high electron-transporting properties and high hole-transporting properties), hole-blocking materials, etc. can be freely combined with the light-emitting layer containing 4,6mDBTP2Pm-II of one embodiment of the present invention as a host material.

[0348] Note that since 4,6mDBTP2Pm-II is a substance having a high electron-transport property, 4,6mDBTP2Pm-II can be used as the electron-transport layer 1140. That is, the organic compound of one embodiment of the present invention can be used for the electron-transport layer.

[0349] Furthermore, by using the organic compound of one embodiment of the present invention in both the light-emitting layer 1130 (particularly, a host material of the light-emitting layer) and the electron-transport layer 1140 , an extremely low driving voltage can be achieved.

[0350] In addition, Figure 2B In the light-emitting element shown, the EL layer 1020 is provided between a pair of electrodes, namely, a first electrode 1010 and a second electrode 1030, over a substrate 1000. The EL layer 1020 includes a hole-injection layer 1110, a hole-transport layer 1120, a light-emitting layer 1130, an electron-transport layer 1140, and an electron-injection layer 1150. Figure 2B The light-emitting element shown has: a second electrode 1030 serving as a cathode on a substrate 1000; an electron injection layer 1150, an electron transport layer 1140, a light-emitting layer 1130, a hole transport layer 1120 and a hole injection layer 1110 stacked in sequence on the second electrode 1030; and a first electrode 1010 serving as an anode on the hole injection layer 1110.

[0351] The method of forming the light-emitting element will be described in detail below.

[0352] The light-emitting element of this embodiment has a structure in which the EL layer 1020 is inserted between a pair of electrodes. The EL layer 1020 has at least a light-emitting layer 1130, and the light-emitting layer 1130 is formed using 4,6mDBTP2Pm-II as a main material. In addition, the EL layer 1020 may have a functional layer (such as a hole injection layer 1110, a hole transport layer 1120, an electron transport layer 1140 or an electron injection layer 1150) in addition to the light-emitting layer 1130. Each electrode (the first electrode 1010 or the second electrode 1030), the light-emitting layer 1130 and each functional layer can be formed by a wet method or a dry method. The wet method includes, for example, a droplet discharge method (inkjet method), a spin coating method or a printing method, and the dry method includes, for example, a vacuum evaporation method, a CVD method or a sputtering method. The wet method can be performed under normal pressure using a simple device and method, and therefore has the effect of simplifying the process and improving productivity. Unlike the wet method, the dry method does not require dissolving the material and can use materials with low solubility in the solution, thus expanding the range of material choices.

[0353] All thin films included in the light-emitting element can be formed by a wet process. In this case, the light-emitting element can be manufactured using only the equipment required for the wet process. Alternatively, the formation of the stacked layers to form the light-emitting layer 1130 can be carried out by a wet process, while the functional layers stacked on the light-emitting layer 1130, the first electrode 1010, etc. can be formed by a dry process. Alternatively, the second electrode 1030 and the functional layer are formed by a dry process before the light-emitting layer 1130 is formed, and the light-emitting layer 1130, the functional layers stacked thereon, and the first electrode 1010 can be formed by a wet process. Needless to say, this embodiment is not limited to this, and the light-emitting element can be formed by a wet process or a dry process as appropriate, depending on the materials used, the required film thickness, and the interface state.

[0354] In this embodiment, a light-emitting element can be manufactured on a substrate made of glass, plastic, etc. By forming a plurality of the light-emitting elements on one substrate, a passive matrix light-emitting device can be manufactured. Alternatively, a thin film transistor (TFT), for example, is formed on a substrate made of glass, plastic, etc., and a light-emitting element can be manufactured on an electrode electrically connected to the TFT. Thus, an active matrix light-emitting device is manufactured in which the TFT controls the driving of the light-emitting element. Note that there are no particular restrictions on the structure of the TFT. A staggered TFT or an inverted staggered TFT can be used. In addition, there are no particular restrictions on the crystallinity of the semiconductor used for the TFT; an amorphous semiconductor or a crystalline semiconductor can be used. In addition, the driving circuit formed on the TFT substrate can be formed by one or both of an N-type and a P-type TFT.

[0355] As described above, a light-emitting element can be manufactured using 4,6mDBTP2Pm-II described in Embodiment 2. By using the organic compound of one embodiment of the present invention in a light-emitting element, a light-emitting element having low driving voltage and high current efficiency can be obtained.

[0356] Furthermore, a light-emitting device (image display device) using the light-emitting element of one embodiment of the present invention obtained by the above method can achieve low power consumption.

[0357] Note that by using the light-emitting element described in this embodiment, a passive matrix light-emitting device or an active matrix light-emitting device in which driving of the light-emitting element is controlled by a thin film transistor (TFT) can be manufactured.

[0358] This embodiment mode can be implemented in combination with other embodiment modes as appropriate.

[0359] Implementation 4

[0360] In this embodiment, as one mode of the present invention, reference is made to Figure 3 A light-emitting element is described in which a phosphorescent iridium metal complex as a first compound, an organic compound containing a pyrimidine skeleton as a second compound, and two or more other organic compounds are used in a light-emitting layer.

[0361] The light-emitting element described in this embodiment has Figure 3 As shown in the figure, an EL layer 203 is provided between a pair of electrodes (a first electrode 201 and a second electrode 202). Furthermore, the EL layer 203 includes at least a light-emitting layer 204. In addition, the EL layer 203 may further include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, and the like. Furthermore, the substances described in Embodiment 1 can be used as the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, and the charge generation layer. Furthermore, in this embodiment, the first electrode 201 functions as an anode, and the second electrode 202 functions as a cathode.

[0362] The light-emitting layer 204 described in this embodiment includes a phosphorescent compound 205 using the phosphorescent iridium metal complex of the first compound described in Embodiment 1, a first organic compound 206, and a second organic compound 207. The phosphorescent compound 205 serves as a guest material in the light-emitting layer 204. Furthermore, at least one of the first organic compound 206 and the second organic compound 207 contains an organic compound containing a pyrimidine skeleton of the second compound, and the one with a higher content in the light-emitting layer 204 serves as a host material for the light-emitting layer 204.

[0363] In the light-emitting layer 204, by dispersing the guest material in the host material, crystallization of the light-emitting layer can be controlled. In addition, concentration quenching due to high concentration of the guest material can be suppressed, and the luminous efficiency of the light-emitting element can be improved.

[0364] Furthermore, the triplet excited state energy level (T1 level) of each of the first organic compound 206 and the second organic compound 207 is preferably higher than the T1 level of the phosphorescent compound 205. This is because if the T1 level of the first organic compound 206 (or the second organic compound 207) is lower than the T1 level of the phosphorescent compound 205, the first organic compound 206 (or the second organic compound 207) quenches the triplet excited state energy of the phosphorescent compound 205 that contributes to luminescence, resulting in a decrease in luminescence efficiency.

[0365] Here, in order to improve the energy transfer efficiency from the host material to the guest material, it is preferable to consider the well-known Förster kinetics as the transfer mechanism between molecules. In the case of the dipole-dipole interaction mechanism and the Dexter mechanism (electron exchange interaction), the emission spectrum of the host material (the fluorescence spectrum during energy transfer from the singlet excited state, the phosphorescence spectrum during energy transfer from the triplet excited state) overlaps significantly with the absorption spectrum of the guest material (more specifically, the spectrum in the absorption band on the longest wavelength (lower energy) side). However, when using a typical phosphorescent host material, it is difficult to overlap the fluorescence spectrum of the host material with the spectrum in the absorption band on the longest wavelength (lower energy) side of the guest material. This is because the phosphorescence spectrum of the host material is located at longer wavelengths (lower energy) than the fluorescence spectrum. Therefore, if this is done, the T1 level of the host material becomes lower than the T1 level of the phosphorescent compound, leading to the aforementioned quenching problem. On the other hand, to avoid the quenching problem, if the T1 level of the host material is set higher than the T1 level of the phosphorescent compound, the fluorescence spectrum of the host material shifts to the shorter wavelength (higher energy) side, so that the fluorescence spectrum does not overlap with the spectrum in the absorption band on the longest wavelength (lower energy) side of the guest material. Therefore, it is generally difficult to overlap the fluorescence spectrum of a host material with the absorption spectrum in the absorption band on the longest wavelength (low energy) side of a guest material and maximize the energy transfer from the singlet excited state of the host material.

[0366] Therefore, in this embodiment, the combination of the first organic compound 206 and the second organic compound 207 is preferably a combination that forms an exciplex. At this time, when the carriers (electrons and holes) recombine in the light-emitting layer 204, the first organic compound 206 and the second organic compound 207 form an exciplex (also called an "exciplex"). As a result, in the light-emitting layer 204, the fluorescence spectrum of the first organic compound 206 and the fluorescence spectrum of the second organic compound 207 are converted into the emission spectrum of the exciplex on the longer wavelength side. Furthermore, if the first organic compound and the second organic compound are selected in order to increase the overlapping portion of the emission spectrum of the exciplex and the absorption spectrum of the guest material, the energy transfer from the singlet excited state can be maximized. In addition, with respect to the triplet excited state, it can also be considered that energy transfer from the exciplex occurs without energy transfer from the host material.

[0367] As the phosphorescent compound 205, a phosphorescent iridium metal complex of the first compound is used. Furthermore, as the combination of the first organic compound 206 and the second organic compound 207, a compound that readily accepts electrons (electron-trapping compound) and a compound that readily accepts holes (hole-trapping compound) are preferably combined. Furthermore, an organic compound containing a pyrimidine skeleton as the second compound can be used as the compound that readily accepts electrons.

[0368] Examples of the compound that readily accepts holes include 4-phenyl-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 4,4′,4″-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1′-TNATA), 2,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9′-bifluorene (abbreviation: DPA2SF), N,N′-bis(9-phenylcarbazol-3-yl)-N,N′-diphenyl-benzene-1,3-diamine (abbreviation: 4,4′,4″-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1′-TNATA), N-(9,9-dimethyl-2-N,N′-diphenylamino-9H-fluoren-7-yl)-N,N-diphenylamine (abbreviated as: DPNF), N-phenyl-N-(4-phenylphenyl)-N-(9-phenyl-9H-carbazol-3-yl)amine (abbreviated as: PCA1BP), N,N′,N″-triphenyl-N,N′,N″-tris(9-phenylcarbazol-3-yl)-benzene-1,3,5-triamine (abbreviated as: PCA3B), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-spiro-9,9′-bifluorene (abbreviated as: PCASF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9, 9′-Bifluorene (abbreviation: DPASF), N,N-di(biphenyl-4-yl)-N-(9-phenyl-9H-carbazol-3-yl)amine (abbreviation: PCzBBA1), N,N′-bis[4-(carbazol-9-yl)phenyl]-N,N′-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), 4,4′-bis[N-(3-methylphenyl)-N-phenylamino]biphenyl (abbreviation: TPD), 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-[9,9-dimethyl-2-{N′-phenyl-N′-(9 ,9-dimethyl-9H-fluoren-2-yl)}amino-9H-fluoren-7-yl]phenylamine (abbreviated as: DFLADFL), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzPCA1), 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzDPA2), 4,4′-bis(N-{4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviated as: DNTPD), 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviated as PCzTPN2), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzPCA2).

[0369] The combination of the first organic compound 206 and the second organic compound 207 is an example of a combination that can form an excimer complex. The emission spectrum of the excimer complex overlaps with the absorption spectrum of the phosphorescent compound 205. Compared with the peak of the absorption spectrum of the phosphorescent compound 205, the peak of the emission spectrum of the excimer complex is at a long wavelength.

[0370] When the first organic compound 206 and the second organic compound 207 are composed of a compound that easily accepts electrons and a compound that easily accepts holes, carrier balance can be controlled by adjusting their mixing ratio. Specifically, the ratio of the first organic compound to the second organic compound is preferably 1:9 to 9:1.

[0371] In the light-emitting element described in this embodiment, energy transfer utilizing the overlap between the emission spectrum of the exciplex and the absorption spectrum of the phosphorescent compound can improve energy transfer efficiency, thereby achieving a light-emitting element with high external quantum efficiency.

[0372] In addition, as another structure included in the present invention, the following structure can also be adopted: two organic compounds other than the phosphorescent compound 205 (guest material) use a host molecule with hole-capturing properties and a host molecule with electron-capturing properties to form the light-emitting layer 204, so as to obtain a phenomenon in which holes and electrons are introduced into the guest molecules present in the two host molecules and the guest molecules are made into an excited state (i.e., Guest Coupled with Complementary Hosts: GCCH, coupling of guest and complementary host).

[0373] In this case, as the host molecule having hole-trapping property and the host molecule having electron-trapping property, the above-mentioned compound that easily accepts holes and the above-mentioned compound that easily accepts electrons can be used, respectively.

[0374] The light-emitting element described in this embodiment is an example of a light-emitting element structure. However, light-emitting elements having other structures described in other embodiments can also be used in a light-emitting device according to one embodiment of the present invention. Furthermore, light-emitting devices having such light-emitting elements can include both passive matrix light-emitting devices and active matrix light-emitting devices. Light-emitting devices having microcavity structures different from those described in other embodiments can also be manufactured. All of these light-emitting devices are encompassed by the present invention.

[0375] Furthermore, when an active matrix light-emitting device is employed, there are no particular restrictions on the TFT structure. For example, staggered TFTs or inversely staggered TFTs may be used as appropriate. Furthermore, the driver circuit formed on the TFT substrate may be formed by either or both N-type and P-type TFTs. Furthermore, there are no particular restrictions on the crystallinity of the semiconductor film used for the TFT. For example, amorphous semiconductor films, crystalline semiconductor films, and oxide semiconductor films may be used.

[0376] Note that the structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0377] Implementation 5

[0378] In this embodiment, as one embodiment of the present invention, a light-emitting element having a structure including a plurality of EL layers with a charge generation layer interposed therebetween (hereinafter referred to as a tandem light-emitting element) is described.

[0379] The light-emitting element described in this embodiment is as follows Figure 4A As shown, a tandem light-emitting element includes a plurality of EL layers (a first EL layer 302 ( 1 ) and a second EL layer 302 ( 2 )) between a pair of electrodes (a first electrode 301 and a second electrode 304 ).

[0380] In this embodiment, the first electrode 301 is an electrode serving as an anode, and the second electrode 304 is an electrode serving as a cathode. The first electrode 301 and the second electrode 304 may have the same structure as in Embodiment 1. Furthermore, although the plurality of EL layers (the first EL layer 302(1) and the second EL layer 302(2)) may have the same structure as that described in Embodiment 1 or Embodiment 3, any one of the EL layers may have the same structure as that described in Embodiment 1 or Embodiment 3. In other words, the first EL layer 302(1) and the second EL layer 302(2) may have the same structure or different structures, and the same structure as in Embodiment 1 or Embodiment 3 may be applied as their structure.

[0381] Furthermore, a charge generation layer 305 is provided between the plurality of EL layers (the first EL layer 302(1) and the second EL layer 302(2)). The charge generation layer 305 has the function of injecting electrons into one EL layer and injecting holes into the other EL layer when a voltage is applied to the first electrode 301 and the second electrode 304. In this embodiment, when a voltage is applied to the first electrode 301 so that its potential is higher than that of the second electrode 304, the charge generation layer 305 injects electrons into the first EL layer 302(1) and injects holes into the second EL layer 302(2).

[0382] Furthermore, from the perspective of light extraction efficiency, the charge generation layer 305 preferably has a property of transmitting visible light (specifically, the charge generation layer 305 has a visible light transmittance of 40% or greater). Furthermore, the charge generation layer 305 functions even when its electrical conductivity is lower than that of the first electrode 301 or the second electrode 304.

[0383] The charge generation layer 305 may have a structure in which an electron acceptor (acceptor) is added to an organic compound having a high hole-transporting property, or a structure in which an electron donor (donor) is added to an organic compound having a high electron-transporting property, or both structures may be stacked.

[0384] In the case of adopting a structure in which an electron acceptor is added to an organic compound with high hole transport properties, aromatic amine compounds such as NPB, TPD, TDATA, MTDATA, or 4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviated as BSPB) can be used as organic compounds with high hole transport properties. The substances mentioned here mainly have a hole mobility of 10 -6 cm 2 However, any substance other than the above substances may be used as long as it is an organic compound with a higher hole-transporting property than an electron-transporting property.

[0385] In addition, as electron acceptors, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinoline and dimethane (abbreviation: F4-TCNQ), chloranil etc. can be given. In addition, transition metal oxides can also be given. In addition, oxides of metals belonging to Groups 4 to 8 in the periodic table can be given. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide and rhenium oxide are preferably used because they have high electron acceptance. In particular, molybdenum oxide is preferably used because it is stable in the atmosphere and its hygroscopicity is low, so it is easy to handle.

[0386] On the other hand, in the case of adopting a structure in which an electron donor is added to an organic compound with high electron transportability, as an organic compound with high electron transportability, for example, a metal complex having a quinoline skeleton or a benzoquinoline skeleton, such as Alq, Almq3, BeBq2 or BAlq, etc. can be used. In addition, a metal complex having an azole ligand or a thiazolyl ligand, such as Zn(BOX)2 or Zn(BTZ)2, etc. can also be used. Furthermore, in addition to the metal complex, PBD, OXD-7, TAZ, BPhen, BCP, etc. can also be used. The substances described here are mainly those with an electron mobility of 10 -6 cm 2 / Vs or more. In addition, an organic compound containing a pyrimidine skeleton as the second compound can also be used. In addition, as long as it is an organic compound with higher electron transport properties than hole transport properties, substances other than the above substances can be used.

[0387] In addition, as electron donors, alkali metals, alkaline earth metals, rare earth metals, metals belonging to Group 2 or Group 13 of the periodic table, and their oxides and carbonates can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, cesium carbonate, etc. are preferably used. In addition, organic compounds such as tetrathianaphthacene can also be used as electron donors.

[0388] In addition, by forming the charge generation layer 305 using the above-mentioned material, an increase in driving voltage caused when EL layers are stacked can be suppressed.

[0389] Although this embodiment mode describes a light-emitting element having two EL layers, Figure 4B As shown in FIG1 , one embodiment of the present invention can be similarly applied to a light-emitting element having n (note that n is 3 or more) stacked EL layers. As in the light-emitting element according to this embodiment, when a plurality of EL layers are provided between a pair of electrodes, by arranging a charge generating layer between the EL layer and the EL layer, light emission in a high brightness area can be achieved while maintaining a low current density. Because the low current density can be maintained, a long-life element can be achieved. In addition, when the light-emitting element is applied to lighting, since the voltage drop due to the resistance of the electrode material can be reduced, uniform light emission over a large area can be achieved. In addition, a light-emitting device that can be driven at a low voltage and has low power consumption can be achieved.

[0390] Furthermore, by making each EL layer emit light of a different color, the light-emitting element as a whole can emit light of a desired color. For example, in a light-emitting element having two EL layers, by making the emission colors of the first EL layer and the second EL layer complementary, the light-emitting element as a whole can emit white light. Note that the term "complementary color relationship" refers to a color relationship that produces a non-color when mixed. In other words, white light can be produced by mixing light emitted from substances emitting complementary colors.

[0391] The same applies to a light-emitting element having three EL layers. For example, when the emission color of the first EL layer is red, the emission color of the second EL layer is green, and the emission color of the third EL layer is blue, the light-emitting element as a whole can emit white light.

[0392] Note that the structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0393] Implementation Method 6

[0394] In this embodiment, referring to Figure 5 A light-emitting device using the light-emitting element described in Embodiments 1 and 3 to 5 will be described.

[0395] The light-emitting device described in this embodiment has an optical micro-resonator (micro-cavity) structure that utilizes the resonance effect of light between a pair of electrodes. Figure 5 The device shown has multiple light-emitting elements, each having a structure including at least an EL layer 455 between a pair of electrodes (a reflective electrode 451 and a semi-transmissive semi-reflective electrode 452). The EL layer 455 includes at least a first light-emitting layer 454B, a second light-emitting layer 454G, and a third light-emitting layer 454R, which serve as light-emitting regions. In addition, the EL layer 455 may also include a hole-injection layer, a hole-transport layer, an electron-transport layer, an electron-injection layer, a charge-generating layer, and the like. Furthermore, at least one of the first light-emitting layer 454B, the second light-emitting layer 454G, and the third light-emitting layer 454R contains a phosphorescent iridium metal complex and an organic compound containing a pyrimidine skeleton.

[0396] In this embodiment, Figure 5 A light-emitting device including light-emitting elements (a first light-emitting element 450R, a second light-emitting element 450G, and a third light-emitting element 450B) having different structures as shown will be described.

[0397] The first light-emitting element 450R has a structure in which the following layers are stacked in this order on a reflective electrode 451: a first transparent conductive layer 453a; an EL layer 455; and a semi-transmissive / semi-reflective electrode 452. Furthermore, the second light-emitting element 450G has a structure in which a second transparent conductive layer 453b, an EL layer 455, and a semi-transmissive / semi-reflective electrode 452 are stacked in this order on a reflective electrode 451. Furthermore, the third light-emitting element 450B has a structure in which an EL layer 455 and a semi-transmissive / semi-reflective electrode 452 are stacked in this order on a reflective electrode 451.

[0398] In addition, the above-mentioned light-emitting elements (the first light-emitting element 450R, the second light-emitting element 450G, and the third light-emitting element 450B) all include a reflective electrode 451 , an EL layer 455 , and a semi-transmissive and semi-reflective electrode 452 .

[0399] The EL layer 455 includes a first light-emitting layer 454B, a second light-emitting layer 454G, and a third light-emitting layer 454R. The first light-emitting layer 454B emits light having a peak in a wavelength range of 420 nm to 480 nm (λ B), the second light-emitting layer 454G emits light having a peak in a wavelength range of 500 nm to 550 nm (λ G ), while the third light emitting layer 454R emits light having a peak in a wavelength region of 600 nm to 760 nm (λ R ). Thus, any light-emitting element (first light-emitting element 450R, second light-emitting element 450G, and third light-emitting element 450B) can emit light that is a superposition of the light emitted from the first light-emitting layer 454B, the second light-emitting layer 454G, and the third light-emitting layer 454R, that is, light with a wide emission spectrum extending to the visible light region. Note that according to the above description, the wavelength length satisfies λ B <λ G <λ R relationship.

[0400] Each light-emitting element described in this embodiment has a structure in which an EL layer 455 is sandwiched between a reflective electrode 451 and a semi-transmissive semi-reflective electrode 452. Light emitted in all directions from each light-emitting layer included in the EL layer 455 resonates with the reflective electrode 451 and the semi-transmissive semi-reflective electrode 452, which function as an optical microresonator (microcavity). The reflective electrode 451 is formed of a reflective conductive material. The reflectivity of the film for visible light is 40% to 100%, preferably 70% to 100%, and the resistivity of the film is 1×10 -2 Ωcm or less. In addition, the semi-transmissive and semi-reflective electrode 452 is formed using a reflective conductive material and a translucent conductive material, and the reflectivity of visible light to the film is 20% to 80%, preferably 40% to 70%, and the resistivity of the film is 1×10 -2 Ωcm or less.

[0401] Furthermore, in this embodiment, the thicknesses of the transparent conductive layers (first transparent conductive layer 453a and second transparent conductive layer 453b) provided in the first light-emitting element 450R and the second light-emitting element 450G are varied, thereby varying the optical path length between the reflective electrode 451 and the semi-transmissive / semi-reflective electrode 452 for each light-emitting element. In other words, between the reflective electrode 451 and the semi-transmissive / semi-reflective electrode 452, light with a resonant wavelength within the broad emission spectrum emitted from each light-emitting layer of each light-emitting element can be intensified, while light with a non-resonant wavelength can be attenuated. Therefore, by varying the optical path length between the reflective electrode 451 and the semi-transmissive / semi-reflective electrode 452 for each element, light of different wavelengths can be extracted.

[0402] The optical path length (also called optical path length) is the value obtained by multiplying the actual distance by the refractive index. In this embodiment, it is the value obtained by multiplying the actual thickness by n (refractive index). In other words, "optical path length = actual thickness × n".

[0403] In addition, the optical path from the reflective electrode 451 to the semi-transmissive semi-reflective electrode 452 in the first light-emitting element 450R is mλ. R / 2 (note that m is a natural number greater than or equal to 1), the optical path from the reflective electrode 451 to the semi-transmissive semi-reflective electrode 452 in the second light-emitting element 450G is mλ G / 2 (note that m is a natural number greater than or equal to 1), and the optical path from the reflective electrode 451 to the semi-transmissive semi-reflective electrode 452 in the third light-emitting element 450B is mλ B / 2 (note that m is a natural number greater than 1).

[0404] As described above, light (λ) emitted from the first light-emitting element 450R is mainly extracted in the third light-emitting layer 454R included in the EL layer 455. R ), light emitted from the second light-emitting layer 454G included in the EL layer 455 is mainly extracted from the second light-emitting element 450G (λ G ), and light emitted in the first light-emitting layer 454B included in the EL layer 455 is mainly extracted from the third light-emitting element 450B (λ B ). In addition, the light taken out from each light emitting element is emitted from the semi-transmissive and semi-reflective electrode 452 side.

[0405] In the above configuration, strictly speaking, the optical path from the reflective electrode 451 to the semi-transmissive reflective electrode 452 is referred to as the distance from the reflective region of the reflective electrode 451 to the reflective region of the semi-transmissive reflective electrode 452. However, since it is difficult to strictly determine the position of the reflective region of the reflective electrode 451 or the semi-transmissive reflective electrode 452, the above-described effect can be fully achieved by assuming that any position of the reflective electrode 451 or the semi-transmissive reflective electrode 452 is the reflective region.

[0406] Next, in the first light-emitting element 450R, since the light reflected by the reflective electrode 451 (first reflected light) from the third light-emitting layer 454R interferes with the light directly incident on the semi-transmissive and semi-reflective electrode 452 from the third light-emitting layer 454R (first incident light), the optical distance between the reflective electrode 451 and the third light-emitting layer 454R is adjusted to (2n R -1)λ R / 4(Note, n R (where ∥ is a natural number greater than or equal to 1). By adjusting the optical path, the phases of the first reflected light and the first incident light can be aligned, thereby amplifying the light emitted from the third light-emitting layer 454R.

[0407] Strictly speaking, the optical path between the reflective electrode 451 and the third light-emitting layer 454R can be referred to as the optical path between the reflective region of the reflective electrode 451 and the light-emitting region of the third light-emitting layer 454R. However, it is difficult to strictly determine the positions of the reflective region of the reflective electrode 451 or the light-emitting region of the third light-emitting layer 454R. Therefore, the aforementioned effects can be fully achieved by assuming that any position of the reflective electrode 451 is the reflective region and any position of the third light-emitting layer 454R is the light-emitting region.

[0408] Next, in the second light-emitting element 450G, since the light reflected by the reflective electrode 451 (second reflected light) from the second light-emitting layer 454G and the light directly incident on the semi-transmissive and semi-reflective electrode 452 from the second light-emitting layer 454G (second incident light) interfere with each other, the optical path between the reflective electrode 451 and the second light-emitting layer 454G is adjusted to (2n G -1)λ G / 4(Note, n G (where ∥ is a natural number greater than or equal to 1). By adjusting the optical path, the phases of the second reflected light and the second incident light can be aligned, thereby amplifying the light emitted from the second light-emitting layer 454G.

[0409] Strictly speaking, the optical path between the reflective electrode 451 and the second light-emitting layer 454G can be referred to as the optical path between the reflective region of the reflective electrode 451 and the light-emitting region of the second light-emitting layer 454G. However, it is difficult to strictly determine the positions of the reflective region of the reflective electrode 451 or the light-emitting region of the second light-emitting layer 454G. Therefore, the aforementioned effects can be fully achieved by assuming that any position of the reflective electrode 451 is the reflective region and any position of the second light-emitting layer 454G is the light-emitting region.

[0410] Next, in the third light-emitting element 450B, the light reflected by the reflective electrode 451 (third reflected light) from the first light-emitting layer 454B interferes with the light directly incident on the semi-transmissive and semi-reflective electrode 452 from the first light-emitting layer 454B (third incident light). Therefore, the optical path between the reflective electrode 451 and the first light-emitting layer 454B is adjusted to (2n B -1)λ B / 4(Note, n B (where ∥ is a natural number greater than or equal to 1). By adjusting the optical path, the phases of the third reflected light and the third incident light can be aligned, thereby amplifying the light emitted from the first light-emitting layer 454B.

[0411] Strictly speaking, the optical path between the reflective electrode 451 and the first light-emitting layer 454B can be referred to as the optical path between the reflective region of the reflective electrode 451 and the light-emitting region of the first light-emitting layer 454B. However, it is difficult to strictly determine the positions of the reflective region of the reflective electrode 451 or the light-emitting region of the first light-emitting layer 454B. Therefore, the aforementioned effects can be fully achieved by assuming that any position of the reflective electrode 451 is the reflective region and any position of the first light-emitting layer 454B is the light-emitting region.

[0412] In the above structure, each light-emitting element is shown as having a structure including multiple light-emitting layers within the EL layer. However, the present invention is not limited to this. For example, a structure may be employed in which the above structure is combined with the tandem (stacked) light-emitting element described in Embodiment 5, where multiple EL layers are provided in a single light-emitting element with a charge generation layer interposed therebetween, and one or more light-emitting layers are formed within each EL layer.

[0413] The light-emitting device shown in this embodiment has a microcavity structure, and even if it has the same EL layer, it can extract light of different wavelengths according to the light-emitting element, so there is no need to apply RGB separately. Therefore, the above structure is advantageous from the perspective of achieving full colorization due to reasons such as easy realization of high precision. In addition, since the luminous intensity in the front direction of a specific wavelength can be enhanced, low power consumption quantization can be achieved. This structure is particularly effective when applied to a color display (image display device) using pixels of three or more colors, but it can also be used for purposes such as lighting.

[0414] Note that the structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0415] Implementation 7

[0416] In this embodiment, referring to Figures 6A to 7B A light-emitting device including a light-emitting element according to one embodiment of the present invention will be described. Figure 6A and Figure 6B The light emitting device shown in FIG. Figure 7A and Figure 7B The light emitting device shown.

[0417] in addition, Figure 6A is a top view of the light emitting device, Figure 6B It is along Figure 6A Cross-sectional view taken along lines AB and CD.

[0418] exist Figure 6AIn the figure, reference numerals 401, 402, and 403 indicated by dotted lines respectively denote a driver circuit portion (source-side driver circuit), a pixel portion, and a finger driver circuit portion (gate-side driver circuit). Reference numeral 404 denotes a sealing substrate, and reference numeral 405 denotes a sealing material. The portion surrounded by the sealing material 405 is a space.

[0419] Note that the leads 408 are used to transmit signals input to the source-side driver circuit 401 and the gate-side driver circuit 403, and receive image signals, clock signals, start signals, reset signals, and the like from an FPC (flexible printed circuit) 409 serving as an external input terminal. Although only an FPC is shown here, a printed wiring board (PWB) may also be attached to the FPC. The light-emitting device in this specification includes not only the light-emitting device itself but also a light-emitting device attached with an FPC or PWB.

[0420] Next, refer to Figure 6B A cross-sectional structure is described. A driver circuit portion and a pixel portion are formed over an element substrate 410 , and here, a source-side driver circuit 401 as the driver circuit portion and one pixel in the pixel portion 402 are shown.

[0421] In addition, a CMOS circuit formed by combining an n-channel TFT 423 and a p-channel TFT 424 is formed in the source-side driver circuit 401. Alternatively, the driver circuit may be formed using various CMOS circuits, PMOS circuits, or NMOS circuits formed using TFTs. Although this embodiment describes a driver-integrated type in which the driver circuit is formed on the substrate, the present invention is not necessarily limited to this type; the driver circuit may be formed externally rather than on the substrate.

[0422] The pixel portion 402 is formed of a plurality of pixels including a switching TFT 411, a current control TFT 412, and a first electrode 413 electrically connected to the drain of the current control TFT 412. Note that an insulator 414 is formed to cover the end of the first electrode 413. Here, the insulator 414 is formed using a positive photosensitive acrylic resin film.

[0423] To improve coverage, a curved surface is formed at the upper or lower end of insulator 414. For example, when a positive-type photosensitive acrylic resin is used as the material for insulator 414, it is preferable to form a curved surface with a curvature radius (0.2 μm to 3 μm) only at the upper end of insulator 414. Insulator 414 can be made of either a negative-type resin that does not dissolve in an etchant after exposure to light, or a positive-type resin that dissolves in an etchant after exposure to light.

[0424] A light-emitting layer 416 and a second electrode 417 are formed on the first electrode 413. A material with a high work function is preferably used as the material for the first electrode 413, which serves as an anode. For example, in addition to single-layer films such as ITO films, indium tin oxide films containing silicon, indium oxide films containing 2 to 20% zinc oxide by weight, titanium nitride films, chromium films, tungsten films, Zn films, and Pt films, a stacked structure of a titanium nitride film and a film primarily composed of aluminum, or a three-layer structure of a titanium nitride film, a film primarily composed of aluminum, and a titanium nitride film can also be used. Furthermore, when a stacked structure is used, the wiring resistance is low, and good ohmic contact can be achieved.

[0425] The light-emitting layer 416 can be formed using various methods, such as vapor deposition using a vapor deposition mask, droplet ejection methods such as inkjet methods, printing, and spin coating. The light-emitting layer 416 contains the organic compound containing a pyrimidine skeleton described in the above embodiment. Alternatively, the light-emitting layer 416 may contain another material, such as a low-molecular-weight material, an oligomer, a dendrimer, or a polymer.

[0426] Furthermore, as a material for the second electrode 417 formed on the light-emitting layer 416 and serving as a cathode, a material having a low work function (for example, Al, Mg, Li, Ca, or alloys or compounds thereof, such as Mg-Ag, Mg-In, or Al-Li) is preferably used. In order to allow light generated in the light-emitting layer 416 to pass through the second electrode 417, the second electrode 417 is preferably a stacked layer of a thin metal film and a transparent conductive film (for example, ITO, indium oxide containing 2 wt % to 20 wt % zinc oxide, indium oxide-tin oxide containing silicon or silicon oxide, or zinc oxide).

[0427] Furthermore, the sealing substrate 404 and the element substrate 410 are bonded together using the sealing material 405, and the light-emitting element 418 is provided in a space 407 surrounded by the element substrate 410, the sealing substrate 404, and the sealing material 405. The space 407 is filled with a filler and, in addition to being filled with an inert gas (such as nitrogen or argon), is sometimes filled with the sealing material 405.

[0428] Epoxy resin is preferably used as the sealing material 405. Furthermore, these materials are preferably materials that are as impermeable as possible to moisture and oxygen. Furthermore, in addition to glass substrates and quartz substrates, plastic substrates made of FRP (Fiberglass-Reinforced Plastics), PVF (polyvinyl fluoride), polyester, acrylic resin, and the like can also be used as the material for the sealing substrate 404.

[0429] As described above, an active matrix light-emitting device including the light-emitting element according to one embodiment of the present invention can be obtained.

[0430] Furthermore, the light-emitting element of the present invention can be used in a passive matrix light-emitting device, and is not limited to the active matrix light-emitting device described above.

[0431] Figure 7A and Figure 7B A perspective view and a cross-sectional view showing a passive matrix light emitting device using the light emitting element of the present invention. Figure 7A is a perspective view of a light emitting device, Figure 7B It is along Figure 7A The cross-sectional view cut along the XY line.

[0432] exist Figure 7A and Figure 7B In the embodiment, an EL layer 504 is provided between a first electrode 502 and a second electrode 503 on a substrate 501. The end of the first electrode 502 is covered by an insulating layer 505. Furthermore, a partition layer 506 is provided on the insulating layer 505. The side walls of the partition layer 506 are inclined so that the distance between the two side walls gradually narrows toward the substrate surface. In other words, the cross-section of the partition layer 506 in the short side direction is trapezoidal, and the bottom side (the side facing the same direction as the surface direction of the insulating layer 505 and in contact with the insulating layer 505) is shorter than the top side (the side facing the same direction as the surface direction of the insulating layer 505 and not in contact with the insulating layer 505). In this way, by providing the partition layer 506, defects of the light-emitting element caused by static electricity, etc. can be prevented.

[0433] As described above, a passive matrix light-emitting device including the light-emitting element according to one embodiment of the present invention can be obtained.

[0434] The light-emitting devices described in this embodiment (active matrix light-emitting device and passive matrix light-emitting device) can both be formed using the light-emitting element described in one embodiment of the present invention, thereby obtaining a light-emitting device with low power consumption.

[0435] In addition, this embodiment mode can be combined with other embodiment modes as appropriate.

[0436] Implementation 8

[0437] This embodiment describes an electronic device including a light-emitting device according to one embodiment of the present invention described in the above embodiment. Examples of such electronic devices include image capture devices such as video cameras and digital cameras, goggle-type displays, navigation systems, audio reproduction devices (such as car audio systems and stereo systems), computers, game consoles, portable information terminals (such as portable computers, mobile phones, portable game consoles, and e-book readers), and image reproduction devices having a recording medium (specifically, devices that reproduce recording media such as digital versatile discs (DVDs) and have a display device capable of displaying images therefrom). Figures 8A to 8D Specific examples of the above-mentioned electronic devices are shown.

[0438] Figure 8A This is a television set according to one embodiment of the present invention, comprising a housing 611, a support base 612, a display unit 613, a speaker unit 614, a video input terminal 615, and the like. In this television set, a light-emitting device according to one embodiment of the present invention can be applied to the display unit 613. Because the light-emitting device according to one embodiment of the present invention can achieve low driving voltage and high current efficiency, the application of the light-emitting device according to one embodiment of the present invention can provide a television set with low power consumption.

[0439] Figure 8B This is a computer according to one embodiment of the present invention, comprising a main body 621, a housing 622, a display unit 623, a keyboard 624, an external connection port 625, a pointing device 626, and the like. In this computer, the display unit 623 can employ the light-emitting device of the present invention. Because the light-emitting device of the present invention can achieve low driving voltage and high current efficiency, employing the light-emitting device according to one embodiment of the present invention can provide a computer with low power consumption.

[0440] Figure 8C This mobile phone, which is one embodiment of the present invention, includes a main body 631, a housing 632, a display portion 633, a sound input portion 634, a sound output portion 635, operation keys 636, an external connection port 637, an antenna 638, and the like. In this mobile phone, the display portion 633 can employ the light-emitting device of the present invention. Because the light-emitting device of the present invention can achieve low driving voltage and high current efficiency, by employing the light-emitting device of one embodiment of the present invention, a mobile phone with low power consumption can be achieved.

[0441] Figure 8D This is an image capture device according to one embodiment of the present invention. The image capture device includes a main body 641, a display unit 642, a housing 643, an external connection port 644, a remote control receiver 645, an image receiver 646, a battery 647, an audio input unit 648, operation keys 649, a viewfinder 650, and the like. In this image capture device, a light-emitting device according to one embodiment of the present invention can be applied to the display unit 642. Because the light-emitting device according to one embodiment of the present invention can achieve high current efficiency with a low driving voltage, the application of the light-emitting device according to one embodiment of the present invention can provide an image capture device with low power consumption.

[0442] As described above, the light-emitting device of one embodiment of the present invention has a wide range of applications and can be applied to electronic devices in various fields. By using the light-emitting device of one embodiment of the present invention, electronic devices with reduced power consumption can be obtained.

[0443] Furthermore, the light-emitting device of one embodiment of the present invention can also be used as a lighting device. Figure 9A This is an example of a liquid crystal display device using the light-emitting device of one embodiment of the present invention as a backlight. Figure 9A The illustrated liquid crystal display device includes a housing 701, a liquid crystal layer 702, a backlight 703, and a housing 704. The liquid crystal layer 702 is connected to a driver IC 705. A light-emitting device according to one embodiment of the present invention is used as the backlight 703, and current is supplied to the backlight 703 via a terminal 706.

[0444] As described above, by using a light-emitting device according to one embodiment of the present invention as a backlight for a liquid crystal display device, a backlight with low power consumption can be obtained. Furthermore, since the light-emitting device according to one embodiment of the present invention is a surface-emitting lighting device, it can be used for a large area, thereby also enabling a large backlight area. Consequently, a liquid crystal display device with low power consumption and a large area can be obtained.

[0445] then, Figure 9B This is an example of a desk lamp in which the light-emitting device of one embodiment of the present invention is used as a lighting device. Figure 9B The desk lamp shown includes a housing 801 and a light source 802, and a light-emitting device according to one embodiment of the present invention is used as the light source 802. Since low driving voltage and high current efficiency can be achieved, the light-emitting device according to one embodiment of the present invention can provide a desk lamp with low power consumption.

[0446] then, Figure 9C This is an example of using a light emitting device according to one embodiment of the present invention as an indoor lighting device 901. Since a light emitting device according to one embodiment of the present invention can also be large-sized, it can be used as a large-area lighting device. In addition, since a light emitting device according to one embodiment of the present invention can be driven at a low voltage to obtain high current efficiency, a low-power-consumption lighting device can be obtained by applying a light emitting device according to one embodiment of the present invention. In this way, a light emitting device according to one embodiment of the present invention can be installed in a room where a light emitting device according to one embodiment of the present invention is used as an indoor lighting device 901. Figure 8A The television device 902 according to one embodiment of the present invention described above is used for viewing public broadcasts or movies.

[0447] In addition, this embodiment mode can be combined with other embodiment modes as appropriate.

[0448] Furthermore, the organic compound containing a pyrimidine skeleton (second compound) of one embodiment of the present invention can be used in organic thin-film solar cells. Specifically, because it has carrier transport properties, it can be used in carrier transport layers and carrier injection layers. Furthermore, because it is photoexcitable, it can be used in power generation layers.

[0449] Example 1

[0450] In this example, as one embodiment of an organic compound containing a pyrimidine skeleton as the second compound, a method for synthesizing 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as 4,6mPnP2Pm) represented by the following structural formula (300) is described.

[0451]

[0452] Synthesis of 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as 4,6mPnP2Pm)

[0453] (C-1) shows a synthesis scheme of 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm).

[0454]

[0455] In a 100 mL round-bottom flask, 0.64 g (4.3 mmol) of 4,6-dichloropyrimidine, 3.2 g (11 mmol) of 3-(phenanthren-9-yl)phenylboronic acid, and 2.3 g (21 mmol) of sodium carbonate were placed. 10 mL of acetonitrile and 20 mL of water were added to the mixture. The mixture was degassed while stirring under reduced pressure. 30 mg (43 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture. Microwaves (2.45 GHz, 100 W) were irradiated for 1.5 hours under an argon atmosphere to heat the mixture while stirring. 1.0 g (3.4 mmol) of 3-(9-phenanthren-9-yl)phenylboronic acid, 0.71 g (6.7 mmol) of sodium carbonate, and 28 mg (40 μmol) of bis(triphenylphosphine)palladium(II) dichloride were added to the mixture, and the mixture was heated for an additional hour with stirring. After heating, water was added to the mixture, and the organic layer was extracted with dichloromethane. The obtained organic layer was washed with a saturated aqueous sodium bicarbonate solution and saturated brine, and magnesium sulfate was added to absorb moisture. The mixture was naturally filtered, and the filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography. In silica gel column chromatography, toluene was used as a developing solvent, and the obtained fraction was concentrated to obtain a solid. It was recrystallized using toluene / hexane to obtain 0.99 g of a white solid of 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as: 4,6mPnP2Pm) with a yield of 40%.

[0456] The resulting white solid of 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as 4,6mPnP2Pm) was purified using the train sublimation method. Purification was performed by heating the solution at 280°C for 14 hours under conditions of 3.7 Pa pressure and an argon flow rate of 5.0 mL / min. After purification, 0.80 g of the white solid 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as 4,6mPnP2Pm) was obtained in a 79% yield.

[0457] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm).

[0458] The obtained compounds are shown below. 1 H NMR data.

[0459] 1 H NMR (CDCl3, 300MHz): δ = 7.50-7.75 (m, 14H), 7.87-7.91 (m, 4H), 8.21-8.31 (m ,5H),8.73(d,J1=8.4Hz,2H),8.78(d,J1=8.4Hz,2H),9.36(d,J1=0.9Hz,1H).

[0460] in addition, Figure 10A and Figure 10B Show 1 H NMR spectrum. In addition, Figure 10B To enlarge Figure 10A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0461] Next, 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as: 4,6mPnP2Pm) obtained in this example was analyzed by liquid chromatography-mass spectrometry (LC / MS analysis).

[0462] In the LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed on an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and a 0.1% formic acid aqueous solution was used as mobile phase B. In addition, 4,6mPnP2Pm was dissolved in toluene at an arbitrary concentration and diluted with acetonitrile to prepare the sample, with an injection volume of 5.0 μL.

[0463] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0464] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0465] The component with m / z = 584.23 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 97 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0466] Depend on Figure 97 The results show that in 4,6mPnP2Pm of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=252, m / z=277, and m / z=541, a peak derived from precursor ions is mainly detected near m / z=585, and a peak derived from dimer ions is mainly detected near m / z=1169. In addition, Figure 97 The results show characteristics derived from 4,6mPnP2Pm, and thus can be said to be important data for identifying 4,6mPnP2Pm contained in the mixture.

[0467] Furthermore, the fragments located near m / z = 541 are believed to be product ions generated by ring-opening of the pyrimidine ring in 4,6mPnP2Pm. This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- and 6-positions of the pyrimidine ring. Therefore, this indicates that 4,6mPnP2Pm according to one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0468] in addition, Figures 98A to 98D The qualitative spectrum (positive ions and negative ions) of 4,6mPnP2Pm measured by a time-of-flight secondary ion mass spectrometer (ToF-SIMS) is shown.

[0469] in addition, Figure 98A The measurement results of positive ions are shown, with the horizontal axis representing m / z in the range of 0 to 500 and the vertical axis representing intensity (arbitrary unit). Figure 98B The measurement results of positive ions are shown, with the horizontal axis representing m / z in the range of 400 to 1200 and the vertical axis representing intensity (arbitrary unit). Figure 98C The measurement results of negative ions are shown, with the horizontal axis representing m / z in the range of 0 to 500 and the vertical axis representing intensity (arbitrary unit). Figure 98D The measurement results of negative ions are shown, with the horizontal axis representing m / z in the range of 400 to 1200 and the vertical axis representing intensity (arbitrary unit).

[0470] TOF SIMS5 (manufactured by ION-TOF) was used as the apparatus, and Bi3 ++ The primary ion was irradiated in a pulsed manner with a pulse width of 7 to 12 nm and an irradiation dose of 8.2×10 10 to 6.7×10 11 ions / cm 2 (1×10 12 ions / cm 2 The acceleration voltage was 25 keV and the current value was 0.2 pA. 4,6mPnP2Pm powder was used as a sample for the measurement.

[0471] Depend on Figure 98A and Figure 98B As a result, it was found that in 4,6mPnP2Pm of one embodiment of the present invention, peaks of product ions of partial skeletons were mainly detected near m / z=252 and m / z=276.

[0472] In addition, by Figure 98C and Figure 98DAs a result, it can be seen that in 4,6mPnP2Pm of one embodiment of the present invention, the peak of the product ion of the partial skeleton is mainly detected near m / z=571, and the peaks derived from the precursor ion are mainly detected near m / z=585 and m / z=595. Figure 98C and Figure 98D The results show characteristics derived from 4,6mPnP2Pm, and thus this is important data for identifying 4,6mPnP2Pm contained in the mixture.

[0473] also, Figure 11A The absorption spectrum of the toluene solution of 4,6mPnP2Pm is shown. Figure 11B Its emission spectrum is shown. Figure 12A The absorption spectrum of the 4,6mPnP2Pm film is shown. Figure 12B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 11A to 12B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, absorption peaks were observed near 281 nm and 299 nm, and peaks of emission wavelengths were observed near 322 nm, 342 nm, and 357 nm. In addition, when measuring a thin film, absorption peaks were observed near 206 nm, 257 nm, 304 nm, and 353 nm, and peaks of emission wavelengths were observed near 406 nm.

[0474] The glass transition temperature of 4,6mPnP2Pm synthesized in this example was measured using a differential scanning calorimeter (DSC). The results showed a glass transition temperature of 126°C. This high glass transition temperature indicates that 4,6mPnP2Pm has good heat resistance. Furthermore, no crystallization peak was observed for 4,6mPnP2Pm, indicating that 4,6mPnP2Pm is not easily crystallized.

[0475] In addition, the electrochemical properties (thin film) of 4,6mPnP2Pm were measured (measurement device: AC-2 manufactured by Rikenki Co., Ltd.) The electrochemical properties (thin film) were measured as follows.

[0476] The ionization potential values measured in air using a photoelectron spectrophotometer (AC-2, manufactured by Riken Keiki Co., Ltd.) were converted to negative values to obtain the HOMO energy level. The LUMO energy level was obtained as follows: assuming a direct transition, the absorption spectrum data of the film described in this example was used to obtain the absorption edge from the Tauc plot. This absorption edge was considered as an optical energy gap and added to the HOMO energy level.

[0477] The results of electrochemical properties (thin film) showed that the HOMO level (highest occupied molecular orbital) of 4,6mPnP2Pm was -5.95 eV, the LUMO level (lowest unoccupied molecular orbital) was -2.70 eV, and the energy gap (Bg) was 3.25 eV.

[0478] From the above results, it can be seen that 4,6mPnP2Pm has a deep HOMO energy level, a shallow LUMO energy level and a wide energy gap (Bg).

[0479] Example 2

[0480] In this example, a method for synthesizing 4,6-bis[3-(naphthalen-1-yl)phenyl]-2-phenylpyrimidine (abbreviated as: 2Ph-4,6mNP2Pm) represented by the following structural formula (311) is described.

[0481]

[0482] Synthesis of 4,6-bis[3-(naphthalen-1-yl)phenyl]-2-phenylpyrimidine (abbreviated as 2Ph-4,6mNP2Pm)

[0483] (D-1) shows a synthesis scheme of 4,6-bis[3-(naphthalen-1-yl)phenyl]-2-phenylpyrimidine (abbreviated as: 2Ph-4,6mNP2Pm).

[0484]

[0485] In a 100 mL three-necked flask, 1.80 g (3.86 mmol) of 4,6-bis(3-bromophenyl)-2-phenylpyrimidine, 4.50 g (9.65 mmol) of 1-naphthaleneboronic acid and 117 mg (386 μmol) of tri(2-methylphenyl)phosphine were placed. 10 mL of 2.0 M potassium carbonate aqueous solution, 15 mL of toluene and 5 mL of ethanol were added to the mixture, and the mixture was stirred under reduced pressure and degassed. 17 mg (77.2 μmol) of palladium (II) acetate was added to the mixture, and the mixture was stirred at 90°C for 8 hours under a nitrogen flow. After stirring, the resulting mixture was filtered and the solid was recovered. Next, the aqueous layer of the filtrate was extracted with toluene. The obtained extract solution and the organic layer were combined and washed with saturated brine, and magnesium sulfate was added to absorb moisture. The mixture was naturally filtered, and the filtrate was concentrated to obtain a solid. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135). The filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (using hexane as the developing solvent and a toluene:hexane ratio of 1:4). The obtained solid was recrystallized from toluene to obtain 1.84 g of a white solid in an 85% yield.

[0486] The resulting white solid (1.66 g) was purified by gradient sublimation under conditions of a pressure of 2.9 Pa and an argon flow rate of 5 mL / min, while heating at 260° C. After purification, 1.52 g of a white solid was obtained with a yield of 92%.

[0487] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 4,6-bis[3-(naphthalen-1-yl)phenyl]-2-phenylpyrimidine (abbreviation: 2Ph-4,6mNP2Pm).

[0488] The obtained compounds are shown below. 1 H NMR data.

[0489] 1 H NMR (CDCl3, 300MHz): δ = 7.42-7.60 (m, 11H), 7.65-7.72 (m, 4H), 7.90-7.96 (m, 6H), 8.10 (s, 1H), 8.36-8.40 (m, 4H), 8.69-8.73 (m, 2H).

[0490] in addition, Figure 13A and Figure 13B Show 1 H NMR spectrum. In addition, Figure 13B To enlarge Figure 13AThe graph shows a range of 7.0 ppm to 9.5 ppm.

[0491] Next, the 4,6-bis[3-(naphthalen-1-yl)phenyl]-2-phenylpyrimidine (abbreviated as: 2Ph-4,6mNP2Pm) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0492] In the LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The chromatographic column used for LC separation was an Acquity UPLC BEH C8 (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and a 0.1% formic acid aqueous solution was used as mobile phase B. In addition, 2Ph-4,6mNP2Pm was dissolved in toluene at an arbitrary concentration and diluted with acetonitrile to adjust the sample, and the injection volume was 5.0 μL.

[0493] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0494] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0495] The component with m / z = 560.23 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 99 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0496] Depend on Figure 99 The results show that in 2Ph-4,6mNP2Pm of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=202, m / z=230, m / z=253, and m / z=441, a peak derived from precursor ions is mainly detected near m / z=561, and a peak derived from dimer ions is mainly detected near m / z=1121. In addition, Figure 99The results show characteristics derived from 2Ph-4,6mNP2Pm, and thus can be said to be important data for identifying 2Ph-4,6mNP2Pm contained in the mixture.

[0497] Furthermore, the fragments located near m / z = 441 are believed to be product ions generated by the ring-opening of the pyrimidine ring in 2Ph-4,6mNP2Pm (with the simultaneous loss of the phenyl group at the 2-position). This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- and 6-positions on the pyrimidine ring. Therefore, this indicates that 2Ph-4,6mNP2Pm according to one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0498] also, Figure 14A The absorption spectrum of 2Ph-4,6mNP2Pm in toluene is shown. Figure 14B Its emission spectrum is shown. Figure 15A The absorption spectrum of the thin film of 2Ph-4,6mNP2Pm is shown. Figure 15B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 14A to 15B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak was observed near 282 nm, and a peak of the emission wavelength was observed near 361 nm. In addition, when measuring a thin film, absorption peaks were observed near 228 nm, 266 nm, 279 nm, 316 nm, and 357 nm, and a peak of the emission wavelength was observed near 393 nm.

[0499] Example 3

[0500] In this example, a method for synthesizing 4,6-bis[3-(triphenylene-2-yl)phenyl]pyrimidine (abbreviated as 4,6mTpP2Pm) represented by the following structural formula (314) is described.

[0501]

[0502] Synthesis of 4,6-bis[3-(triphenylene-2-yl)phenyl]pyrimidine (abbreviated as 4,6mTpP2Pm)

[0503] (E-1) shows a synthesis scheme of 4,6-bis[3-(triphenylene-2-yl)phenyl]pyrimidine (abbreviated as: 4,6mTpP2Pm).

[0504]

[0505] In a 100 mL round-bottom flask, 0.65 g (4.38 mmol) of 4,6-dichloropyrimidine, 3.83 g (11.0 mmol) of 3-(triphenylene-2-yl)phenylboronic acid, and 2.33 g (22.0 mol) of sodium carbonate were placed. To this mixture were added 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water. The mixture was stirred while reducing the pressure to degas. 41 mg (52.6 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. The reaction vessel was heated by irradiating with microwaves (2.45 GHz, 100 W) for 1.5 hours under an argon stream. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent, and then using toluene:ethyl acetate = 10:1). The resulting solid was recrystallized from toluene, yielding 1.12 g of a white solid in a 37% yield.

[0506] The resulting white solid (0.88 g) was purified by gradient sublimation under conditions of a pressure of 2.8 Pa and an argon flow rate of 5 mL / min, while heating at 370° C. After purification, 0.71 g of a light yellow solid was obtained in a yield of 81%.

[0507] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 4,6-bis[3-(triphenylene-2-yl)phenyl]pyrimidine (abbreviation: 4,6mTpP2Pm).

[0508] The following shows the obtained material 1 H NMR data.

[0509] 1 H NMR (CDCl3, 300MHz): δ = 7.66-7.76 (m, 10H), 7.98-8.02 (m, 4H), 8.23 (d, J1 = 7.8Hz, 2H), 8.34 (s, 1H), 8.62-8.81 (m, 12H), 8.95 (s, 2H), 9.46 (s, 1H).

[0510] in addition, Figure 16A and Figure 16B Show 1 H NMR spectrum. In addition, Figure 16B To enlarge Figure 16A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0511] Next, 4,6-bis[3-(triphenylene-2-yl)phenyl]pyrimidine (abbreviated as: 4,6mTpP2Pm) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0512] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. In addition, 4,6mTpP2Pm was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample, with an injection volume of 5.0 μL.

[0513] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0514] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0515] The component with m / z = 684.26 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 100 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0516] Depend on Figure 100 The results show that in 4,6mTpP2Pm of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=327 and m / z=641, and precursor ions are mainly detected near m / z=685. Figure 100 The results show characteristics derived from 4,6mTpP2Pm, and thus can be said to be important data for identifying 4,6mTpP2Pm contained in the mixture.

[0517] Furthermore, the product ions near m / z = 641 are believed to be generated by ring-opening of the pyrimidine ring in 4,6mTpP2Pm. This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- and 6-positions of the pyrimidine ring. Therefore, this indicates that 4,6mTpP2Pm according to one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0518] also, Figure 17A The absorption spectrum of a toluene solution of 4,6mTpP2Pm is shown. Figure 17B Its emission spectrum is shown. Figure 18A The absorption spectrum of the thin film of 4,6mTpP2Pm is shown. Figure 18B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. 17A to 18B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak is observed near 281 nm, and a peak of the emission wavelength is observed near 363 nm. In addition, when measuring a thin film, absorption peaks are observed near 271 nm and 320 nm, and a peak of the emission wavelength is observed near 423 nm.

[0519] Example 4

[0520] In this example, a method for synthesizing 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II) represented by the following structural formula (400) is described.

[0521]

[0522] Synthesis of 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II)

[0523] (F-1) shows a synthesis scheme of 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-II).

[0524]

[0525] In a 100 mL eggplant-shaped flask, place 1.0 g (6.7 mmol) of 4,6-dichloropyrimidine, 5.1 g (17 mmol) of 3-(dibenzothiophene-4-yl)-phenylboronic acid, 3.5 g (34 mmol) of sodium carbonate, 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU), and 10 mL of water. Stir the mixture while reducing the pressure to degas. Add 56 mg (81 μmol) of bis(triphenylphosphine)palladium(II) dichloride to the mixture, and replace the air with argon. Heat the reaction vessel with microwaves (2.45 GHz, 100 W) for 1.5 hours while stirring. After heating, add water to the mixture and filter to obtain a filter residue. Wash the resulting solid with dichloromethane and ethanol. Toluene was added to the resulting solid, and the mixture was suction filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a solid. The resulting solid was recrystallized using toluene to obtain 2.52 g of a white solid in a yield of 63%.

[0526] 2.50 g of the obtained white solid was purified by gradient sublimation method by heating at 300° C. under the conditions of pressure of 3.6 Pa and argon flow rate of 5 mL / min. After purification, 1.98 g of white solid was obtained with a yield of 79%.

[0527] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II).

[0528] The obtained compounds are shown below. 1 H NMR data.

[0529] 1 H NMR (CDCl3, 300MHz): δ=7.41-7.51(m,4H),7.58-7.62(m,4H),7.68-7.79(m,4H),8.73(dt,J 1=8.4Hz,J2=0.9Hz,2H),8.18-8.27(m,7H),8.54(t,J1=1.5Hz,2H),9.39(d,J1=0.9Hz,1H).

[0530] in addition, Figure 19A and Figure 19B Show 1 H NMR spectrum. In addition, Figure 19BTo enlarge Figure 19A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0531] Next, the 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-II) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0532] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and a 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 4,6mDBTP2Pm-II was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample, with an injection volume of 5.0 μL.

[0533] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0534] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0535] The component with m / z = 596.14 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 101 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0536] Depend on Figure 101The results show that in 4,6mDBTP2Pm-II of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z = 252, near m / z = 258, near m / z = 284, near m / z = 309, and near m / z = 553, a peak derived from precursor ions is mainly detected near m / z = 597, and a peak derived from dimer ions is mainly detected near m / z = 1193. In addition, Figure 101 The results show characteristics derived from 4,6mDBTP2Pm-II, and thus can be said to be important data for identifying 4,6mDBTP2Pm-II contained in the mixture.

[0537] Furthermore, the product ion near m / z = 553 is believed to be a fragment generated by the ring-opening of the pyrimidine ring in 4,6mDBTP2Pm-II. This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- or 6-position of the pyrimidine ring. Therefore, this indicates that 4,6mDBTP2Pm-II according to one embodiment of the present invention contains a pyrimidine ring substituted at the 4- or 6-position.

[0538] in addition, Figures 102A to 102D The qualitative spectrum (positive ion and negative ion) of 4,6mDBTP2Pm-II measured by time-of-flight secondary ion mass spectrometry (ToF-SIMS) is shown.

[0539] in addition, Figure 102A The measurement results of positive ions are shown, with the horizontal axis representing m / z in the range of 0 to 500 and the vertical axis representing intensity (arbitrary unit). Figure 102B The measurement results of positive ions are shown, with the horizontal axis representing m / z in the range of 400 to 1200 and the vertical axis representing intensity (arbitrary unit). Figure 102C The measurement results of negative ions are shown, with the horizontal axis representing m / z in the range of 0 to 500 and the vertical axis representing intensity (arbitrary unit). Figure 102D The measurement results of negative ions are shown, with the horizontal axis representing m / z in the range of 400 to 1200 and the vertical axis representing intensity (arbitrary unit).

[0540] TOF SIMS5 (manufactured by ION-TOF) was used as the apparatus, and Bi3 ++ The primary ion was irradiated in a pulsed manner with a pulse width of 7 to 12 nm and an irradiation dose of 8.2×10 10 to 6.7×10 11 ions / cm 2 (1×10 12 ions / cm 2The acceleration voltage was 25 keV and the current value was 0.2 pA. In addition, the measurement was performed using 4,6mDBTP2Pm-II powder as a sample.

[0541] Depend on Figure 102A and Figure 102B The results show that in 4,6mDBTP2Pm-II of one embodiment of the present invention, the peaks of product ions of partial skeletons are mainly detected near m / z=184, m / z=258, m / z=271, m / z=284, m / z=296, m / z=309 and m / z=597.

[0542] In addition, by Figure 102C and Figure 102D The results show that in 4,6mDBTP2Pm-II of one embodiment of the present invention, the peak of the product ion of the partial skeleton is mainly detected near m / z=583, and the peaks derived from the precursor ion are mainly detected near m / z=597, m / z=607, and m / z=627. In addition, Figure 102C and Figure 102D The results show characteristics derived from 4,6mDBTP2Pm-II, and thus this is important data for identifying 4,6mDBTP2Pm-II contained in the mixture.

[0543] In addition, a GC / MS instrument (manufactured by Thermo Fisher Scientific Inc., ITQ1100 ion trap GC / MS) was used. n 4,6mDBTP2Pm-II, one embodiment of the present invention, was measured using a direct injection system (DEP). The mode was EI+, with an ionization voltage of 70 eV, an emission current of 250 μA, and an electron lens setting of 15 V. The sample temperature was raised to 1000°C at a heating rate of 10°C / sec. The measurement results show that in 4,6mDBTP2Pm-II (m / z = 596.14), one embodiment of the present invention, peaks of partial skeleton product ions were detected primarily near m / z = 184, m / z = 282, m / z = 298, m / z = 310, m / z = 552, and m / z = 568, while a peak derived from the precursor ion was primarily detected near m / z = 596. These results demonstrate characteristics derived from 4,6mDBTP2Pm-II, making them important data for identifying 4,6mDBTP2Pm-II contained in a mixture.

[0544] Furthermore, the product ions near m / z = 184 are believed to be fragments derived from dibenzothiophene in 4,6mDBTP2Pm-II. This product ion form is a characteristic feature of organic compounds according to one embodiment of the present invention having a dibenzothiophene skeleton. Therefore, this indicates that 4,6mDBTP2Pm-II according to one embodiment of the present invention contains a dibenzothiophene skeleton.

[0545] Furthermore, the product ions near m / z = 552 and m / z = 568 are believed to be fragments generated by the ring-opening of the pyrimidine ring in 4,6mDBTP2Pm-II. This product ion pattern is a characteristic feature of heterocyclic compounds of one embodiment of the present invention that have substitutions at the 4- and 6-positions on the pyrimidine ring. This indicates that 4,6mDBTP2Pm-II of one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0546] also, Figure 20A The absorption spectrum of the toluene solution of 4,6mDBTP2Pm-II is shown. Figure 20B Its emission spectrum is shown. Figure 21A The absorption spectrum of the thin film of 4,6mDBTP2Pm-II is shown. Figure 21B The emission spectrum is shown. Absorption spectra were measured using a UV-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution was placed in a quartz cell, and a thin film was deposited on a quartz substrate to prepare a sample for measurement. The absorption spectrum of the solution was obtained by subtracting the absorption spectrum measured with only toluene placed in the quartz cell. The absorption spectrum of the thin film was obtained by subtracting the absorption spectrum of the quartz substrate.

[0547] exist Figures 20A to 21B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak was observed near 282 nm, and a peak of the emission wavelength was observed near 376 nm. In addition, when measuring a thin film, absorption peaks were observed near 244 nm, 265 nm, 290 nm, 317 nm, and 334 nm, and a peak of the emission wavelength was observed near 396 nm.

[0548] Example 5

[0549] In this example, a method for synthesizing 2,4-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 2,4mDBTP2Pm-II) represented by the following structural formula (401) is described.

[0550]

[0551] Synthesis of 2,4-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 2,4mDBTP2Pm-II)

[0552] (G-1) shows a synthesis scheme of 2,4-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 2,4mDBTP2Pm-II).

[0553]

[0554] In a 100 mL eggplant-shaped flask, 0.75 g (5.03 mmol) of 2,4-dichloropyrimidine, 3.82 g (12.6 mmol) of 3-(dibenzothiophen-4-yl)phenylboronic acid, and 2.67 g (25.2 mmol) of sodium carbonate were placed. To this mixture were added 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water. The mixture was degassed by stirring while reducing the pressure. 42 mg (60.3 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. Under an argon flow, the reaction vessel was heated by irradiating it with microwaves (2.45 GHz, 100 W) for 55 minutes. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene, yielding 1.87 g of a white solid in a 62% yield.

[0555] 1.80 g of the obtained solid was purified by gradient sublimation method by heating at 300° C. under the conditions of a pressure of 5.1 Pa and an argon flow rate of 10 mL / min. After purification, 1.98 g of a white solid was obtained with a yield of 68%.

[0556] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 2,4-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 2,4mDBTP2Pm-II).

[0557] The following shows the obtained material 1 H NMR data.

[0558] 1H NMR (CDCl3, 300MHz): δ = 7.39-7.76 (m, 13H), 7.90 (dt, J1 = 7.8Hz, J2 = 1.5Hz, 2H), 8.13-8.20 (m, 4H), 8.32 (dt, J1 = 8.1Hz, J 2=1.5Hz, 1H), 8.68 (dt, J1=7.8Hz, J2=1.5Hz, 1H), 8.72 (t, J1=1.5Hz, 1H), 8.92 (d, J1=5.4Hz, 1H), 9.07 (t, J1=1.5Hz, 1H).

[0559] in addition, Figure 22A and Figure 22B Show 1 H NMR spectrum. In addition, Figure 22B To enlarge Figure 22A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0560] also, Figure 23A The absorption spectrum of the toluene solution of 2,4mDBTP2Pm-II is shown. Figure 23B Its emission spectrum is shown. Figure 24A The absorption spectrum of the thin film of 2,4mDBTP2Pm-II is shown. Figure 24B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 23A to 24B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak is observed near 283 nm, and a peak of the emission wavelength is observed near 356 nm. In addition, when measuring a thin film, absorption peaks are observed near 244 nm, 226 nm, 287 nm, 318 nm, and 335 nm, and a peak of the emission wavelength is observed near 385 nm.

[0561] Example 6

[0562] In this example, a method for synthesizing 2,5-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 2,5mDBTP2Pm-II) represented by the following structural formula (402) is described.

[0563]

[0564] Synthesis of 2,5-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 2,5mDBTP2Pm-II)

[0565] (H-1) shows a synthesis scheme of 2,5-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 2,5mDBTP2Pm-II).

[0566]

[0567] In a 100 mL eggplant-shaped flask, 0.97 g (5.03 mmol) of 5-bromo-2-chloropyrimidine, 3.82 g (12.6 mmol) of 3-(dibenzothiophene-4-yl)phenylboronic acid, and 2.67 g (25.2 mmol) of sodium carbonate were placed. 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water were added to the mixture. The mixture was stirred while reducing the pressure to degas. 42 mg (60.3 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. Under an argon stream, the reaction vessel was heated by irradiating microwaves (2.45 GHz, 100 W) for 1.5 hours. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene, yielding 1.87 g of a white solid in a 62% yield.

[0568] 1.81 g of the obtained solid was purified by gradient sublimation method by heating at 335° C. under the conditions of a pressure of 5.1 Pa and an argon flow rate of 10 mL / min. After purification, 1.52 g of a white solid was obtained with a yield of 84%.

[0569] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 2,5-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 2,5mDBTP2Pm-II).

[0570] The following shows the obtained material 1 H NMR data.

[0571] 1H NMR (CDCl3, 300MHz): δ= 7.46-7.51(m,4H),7.55-7.75(m,7H),7.82-7.88(m,3H),7.92(dt,J1=7.8Hz,J2=1.5Hz,1H),8.09(t,J1 =1.5Hz,1H),8.18-8.23(m,4H),8.60(dt,J1=8.4Hz,J2=1.5Hz,1H),8.92(t,J1=1.8Hz,1H),9.17(s,2H).

[0572] in addition, Figure 25A and Figure 25B Show 1 H NMR spectrum. In addition, Figure 25B To enlarge Figure 25A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0573] Next, the 2,5-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 2,5mDBTP2Pm-II) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0574] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 2,5mDBTP2Pm-II was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample, with an injection volume of 5.0 μL.

[0575] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0576] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0577] The component with m / z = 596.14 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 103 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0578] Depend on Figure 103 The results show that in 2,5mDBTP2Pm-II of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=271 and m / z=284, peaks derived from precursor ions are mainly detected near m / z=597, and peaks derived from dimer ions are mainly detected near m / z=1193. Figure 103 The results show characteristics derived from 2,5mDBTP2Pm-II, and thus can be said to be important data for identifying 2,5mDBTP2Pm-II contained in the mixture.

[0579] also, Figure 26A The absorption spectrum of a toluene solution of 2,5mDBTP2Pm-II is shown. Figure 26B Its emission spectrum is shown. Figure 27A The absorption spectrum of the thin film of 2,5mDBTP2Pm-II is shown. Figure 27B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 26A to 27B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak was observed near 287 nm, and a peak of the emission wavelength was observed near 353 nm. In addition, when measuring a thin film, absorption peaks were observed near 244 nm, 268 nm, 289 nm, 326 nm, and 334 nm, and a peak of the emission wavelength was observed near 391 nm.

[0580] Example 7

[0581] In this example, a method for synthesizing 4,6-bis[3-(2,8-diphenyl-dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-III) represented by the following structural formula (412) is described.

[0582]

[0583] Synthesis of 4,6-bis[3-(2,8-diphenyl-dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-III)

[0584] (I-1) shows a synthesis scheme of 4,6-bis[3-(2,8-diphenyl-dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-III).

[0585]

[0586] In a 100 mL round-bottom flask, 0.50 g (3.33 mmol) of 4,6-dichloropyrimidine, 3.80 g (8.33 mmol) of 3-(2,8-diphenyl-dibenzothiophen-4-yl)phenylboronic acid, and 1.77 g (16.7 mmol) of sodium carbonate were placed. To this mixture were added 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water. The mixture was degassed by stirring while reducing the pressure. 45 mg (63.7 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. Under an argon flow, the reaction vessel was heated by irradiating with microwaves (2.45 GHz, 100 W) for 1.5 hours. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene, yielding 1.74 g of a white solid in a 58% yield.

[0587] 1.19 g of the obtained solid was purified by gradient sublimation method by heating at 380° C. under the conditions of a pressure of 2.5 Pa and an argon flow rate of 5 mL / min. After purification, 1.04 g of a white solid was obtained with a yield of 87%.

[0588] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 4,6-bis[3-(2,8-diphenyl-dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-III).

[0589] The following shows the obtained material 1H NMR data.

[0590] 1 H NMR (CDCl3, 300MHz): δ = 7.37-7.42 (m, 4H), 7.50 (t, J1 = 7.5Hz, 8H), 7.65-7.83 (m, 16H), 7.97 (dt, J1 = 7.8Hz ,J1=1.5Hz,2H),8.29-8.33(m,3H),8.43(t,J1=1.5Hz,4H),8.62(t,J1=1.5Hz,2H),9.41(d,J1=1.2Hz,1H).

[0591] in addition, Figure 28A and Figure 28B Show 1 H NMR spectrum. In addition, Figure 28B To enlarge Figure 28A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0592] Next, the 4,6-bis[3-(2,8-diphenyl-dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-III) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0593] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 4,6mDBTP2Pm-III was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample, with an injection volume of 5.0 μL.

[0594] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0595] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0596] The component with m / z = 900.26 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 104 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0597] Depend on Figure 104 The results show that in 4,6mDBTP2Pm-III of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=421, m / z=437, and m / z=857, and a peak derived from precursor ions is mainly detected near m / z=901. Figure 104 The results show characteristics derived from 4,6mDBTP2Pm-III, and thus can be said to be important data for identifying 4,6mDBTP2Pm-III contained in the mixture.

[0598] Furthermore, the product ions at around m / z = 857 are believed to be generated by ring-opening of the pyrimidine ring in 4,6mDBTP2Pm-III. This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- and 6-positions of the pyrimidine ring. This indicates that 4,6mDBTP2Pm-III according to one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0599] also, Figure 29A The absorption spectrum of the toluene solution of 4,6mDBTP2Pm-III is shown. Figure 29B Its emission spectrum is shown. Figure 30A The absorption spectrum of the thin film of 4,6mDBTP2Pm-III is shown. Figure 30B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 29A to 30B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak is observed near 292nm, and a peak of the emission wavelength is observed near 372nm. In addition, when measuring a thin film, absorption peaks are observed near 264nm, 301nm, and 354nm, and a peak of the emission wavelength is observed near 402nm.

[0600] Example 8

[0601] In this example, a method for synthesizing 4,6-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBFP2Pm-II) represented by the following structural formula (430) is described.

[0602]

[0603] Synthesis of 4,6-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBFP2Pm-II)

[0604] (J-1) shows a synthesis scheme of 4,6-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as: 4,6mDBFP2Pm-II).

[0605]

[0606] In a 100 mL eggplant-shaped flask, 0.79 g (5.31 mmol) of 4,6-dichloropyrimidine, 3.82 g (13.3 mmol) of 3-(dibenzofuran-4-yl)-phenylboronic acid and 2.82 g (26.6 mmol) of sodium carbonate were placed, and 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water were added to the mixture. The mixture was stirred while reducing the pressure to degas. 45 mg (63.7 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. Under an argon stream, the reaction vessel was irradiated with microwaves (2.45 GHz, 100 W) for 1.5 hours to heat it. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene to obtain 1.56 g of a white solid in a yield of 52%.

[0607] 1.51 g of the obtained solid was purified by gradient sublimation method by heating at 280° C. under the conditions of a pressure of 3.5 Pa and an argon flow rate of 5 mL / min. After purification, 1.23 g of a white solid was obtained with a yield of 81%.

[0608] By nuclear magnetic resonance ( 1H NMR) confirmed that the compound was the target 4,6-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBFP2Pm-II).

[0609] The following shows the obtained material 1 H NMR data.

[0610] 1 H NMR (CDCl3, 300MHz): δ = 7.34-7.50 (m, 6H), 7.57 (d, J1 = 8.4Hz, 2H), 7.73 (t, J1 = 7.8Hz, 4H), 7.98-8.01 (m, 4H) ,8.11(d,J1=7.8Hz,2H),8.26(d,J1=7.8Hz,2H),8.33(d,J1=0.9Hz,1H),8.69(t,J1=1.5Hz,2H),9.41(s,1H).

[0611] in addition, Figure 31A and Figure 31B Show 1 H NMR spectrum. In addition, Figure 31B To enlarge Figure 31A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0612] Next, the 4,6-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBFP2Pm-II) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0613] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 4,6mDBFP2Pm-II was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample. The injection volume was 5.0 μL.

[0614] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0615] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0616] The component with m / z = 564.18 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 105 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0617] Depend on Figure 105 The results show that in 4,6mDBFP2Pm-II of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z = 215, near m / z = 239, near m / z = 270, and near m / z = 521, a peak derived from precursor ions is mainly detected near m / z = 565, and a peak derived from dimer ions is mainly detected near m / z = 1129. In addition, Figure 105 The results show characteristics derived from 4,6mDBFP2Pm-II, and thus can be said to be important data for identifying 4,6mDBFP2Pm-II contained in the mixture.

[0618] Furthermore, the product ions near m / z = 521 are believed to be generated by ring-opening of the pyrimidine ring in 4,6mDBFP2Pm-II. This product ion pattern is a characteristic feature of organic compounds according to one embodiment of the present invention that have substitutions at the 4- and 6-positions of the pyrimidine ring. Therefore, this indicates that 4,6mDBFP2Pm-II according to one embodiment of the present invention contains pyrimidine rings substituted at the 4- and 6-positions.

[0619] also, Figure 32A The absorption spectrum of the toluene solution of 4,6mDBFP2Pm-II is shown. Figure 32B Its emission spectrum is shown. Figure 33A The absorption spectrum of the thin film of 4,6mDBFP2Pm-II is shown. Figure 33B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 32A to 33BIn the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak was observed near 289 nm, and a peak of the emission wavelength was observed near 383 nm. In addition, when measuring a thin film, absorption peaks were observed near 206 nm, 248 nm, 290 nm, 303 nm, and 315 nm, and a peak of the emission wavelength was observed near 383 nm.

[0620] Example 9

[0621] In this example, a method for synthesizing 2,4-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 2,4mDBFP2Pm-II) represented by the following structural formula (431) is described.

[0622]

[0623] Synthesis of 2,4-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 2,4mDBFP2Pm-II)

[0624] (K-1) shows a synthesis scheme of 2,4-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as: 2,4mDBFP2Pm-II).

[0625]

[0626] In a 100 mL eggplant-shaped flask, 0.79 g (5.31 mmol) of 2,4-dichloropyrimidine, 3.82 g (13.3 mmol) of 3-(dibenzofuran-4-yl)-phenylboronic acid, and 2.82 g (26.6 mmol) of sodium carbonate were placed. 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water were added to the mixture. The mixture was stirred while reducing the pressure to degas. 45 mg (63.7 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. The reaction vessel was heated by irradiating microwaves (2.45 GHz, 100 W) for 1 hour under an argon stream. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene, yielding 1.89 g of a white solid in a 63% yield.

[0627] 1.93 g of the obtained solid was purified by gradient sublimation method by heating at 270° C. under the conditions of a pressure of 3.3 Pa and an argon flow rate of 5 mL / min. After purification, 1.43 g of a white solid was obtained in a yield of 74%.

[0628] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 2,4-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 2,4mDBFP2Pm-II).

[0629] The following shows the obtained material 1 H NMR data.

[0630] 1 H NMR (CDCl3, 300MHz): δ=7.31-7.45(m,6H),7.54-7.57(m,2H),7.68-7.77(m,5H),7.92-8.00(m,4H),8.07-8.13(m,2H),8.33(dt,J1 =7.8Hz, J2=1.2Hz, 1H), 8.70(dt, J1=8.1Hz, J2=1.5Hz, 1H), 8.89(t, J1=1.5Hz, 1H), 8.93(d, J1=5.4Hz, 1H), 9.22(t, J1=1.5Hz, 1H).

[0631] in addition, Figure 34A and Figure 34B Show 1 H NMR spectrum. In addition, Figure 34B To enlarge Figure 34A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0632] Next, the 2,4-bis[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 2,4mDBFP2Pm-II) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0633] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 2,4mDBFP2Pm-II was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample. The injection volume was 5.0 μL.

[0634] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0635] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0636] The component with m / z = 564.18 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 106 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0637] Depend on Figure 106 The results show that in 2,4mDBFP2Pm-II of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z=239 and m / z=268, peaks derived from precursor ions are mainly detected near m / z=565, and peaks derived from dimer ions are mainly detected near m / z=1129. Figure 106 The results show characteristics derived from 2,4mDBFP2Pm-II, and thus can be said to be important data for identifying 2,4mDBFP2Pm-II contained in the mixture.

[0638] also, Figure 35A The absorption spectrum of the toluene solution of 2,4mDBFP2Pm-II is shown. Figure 35B Its emission spectrum is shown. Figure 36AThe absorption spectrum of the thin film of 2,4mDBFP2Pm-II is shown. Figure 36B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 35A to 36B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak is observed near 283 nm, and a peak of the emission wavelength is observed near 413 nm. In addition, when measuring a thin film, an absorption peak is observed near 316 nm, and a peak of the emission wavelength is observed near 387 nm.

[0639] Example 10

[0640] In this example, a method for synthesizing 2,5-[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 2,5mDBFP2Pm-II) represented by the following structural formula (432) is described.

[0641]

[0642] Synthesis of 2,5-[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as 2,5mDBFP2Pm-II)

[0643] (L-1) shows a synthesis scheme of 2,5-[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviated as: 2,5mDBFP2Pm-II).

[0644]

[0645] In a 100 mL eggplant-shaped flask, 1.03 g (5.31 mmol) of 5-bromo-2-chloropyrimidine, 3.82 g (13.3 mmol) of 3-(dibenzofuran-4-yl)-phenylboronic acid, and 2.82 g (26.6 mmol) of sodium carbonate were placed. 20 mL of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) and 10 mL of water were added to the mixture. The mixture was stirred while reducing the pressure to degas. 45 mg (63.7 μmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and the air was replaced with argon. The reaction vessel was heated by irradiating microwaves (2.45 GHz, 100 W) for 2.5 hours under an argon stream. After heating, water was added to the mixture and filtered to obtain a filter residue. The resulting solid was washed with ethanol and dichloromethane. Toluene was added to the solid, and the mixture was filtered through celite (Wako Pure Chemical Industries, Ltd., Catalog No. 531-16855), alumina, and magnesium silicate (Wako Pure Chemical Industries, Ltd., Catalog No. 540-00135). The filtrate was concentrated to obtain a white solid. The solid was purified by silica gel column chromatography (using toluene as the developing solvent). The obtained solid was recrystallized from toluene, yielding 1.80 g of a white solid in a 60% yield.

[0646] 1.80 g of the obtained solid was purified by gradient sublimation method by heating at 300° C. under the conditions of a pressure of 3.3 Pa and an argon flow rate of 5 mL / min. After purification, 1.51 g of a white solid was obtained with a yield of 84%.

[0647] By nuclear magnetic resonance ( 1 H NMR) confirmed that the compound was the target 2,5-[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 2,5mDBFP2Pm-II).

[0648] The following shows the obtained material 1 H NMR data.

[0649] 1 H NMR (CDCl3, 300MHz): δ = 7.35-7.41 (m, 2H), 7.45-7.52 (m, 4H), 7.62-7.78 (m, 7H), 7.96-8.03 (m, 5H), 8.14 (dt, J1 = 7.8Hz, J 2=1.5Hz,1H),8.21(dd,J1=2.7Hz,J2=1.5Hz,1H),8.59(dt,J1=7.8Hz,J2=1.5Hz,1H),9.03(t,J1=1.2Hz,1H),9.18(s,2H).

[0650] in addition, Figure 37A and Figure 37B Show 1 H NMR spectrum. In addition, Figure 37B To enlarge Figure 37A The graph shows a range of 7.0 ppm to 9.5 ppm.

[0651] Next, the 2,5-[3-(dibenzofuran-4-yl)phenyl]pyrimidine (abbreviation: 2,5mDBFP2Pm-II) obtained in this example was analyzed by liquid chromatography-mass spectrometry analysis (LC / MS analysis).

[0652] In LC / MS analysis, LC (liquid chromatography) separation was performed using an Acquity UPLC manufactured by Waters, and MS analysis (mass spectrometry) was performed using a Xevo G2 Tof MS manufactured by Waters. The LC separation was performed using an Acquity UPLC BEH C8 column (2.1×100 mm, 1.7 μm), and the column temperature was 40°C. Acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. Separately, 2,5mDBFP2Pm-II was dissolved in chloroform at an arbitrary concentration and diluted with acetonitrile to prepare the sample. The injection volume was 5.0 μL.

[0653] LC separation utilizes a gradient method that changes the mobile phase composition. From 0 to 1 minute after the start of detection, the ratio is set to 40:60 mobile phase A:B. The composition is then changed to 95:5 mobile phase A:B 10 minutes after the start of detection. The composition ratio is linearly varied.

[0654] In MS analysis, ionization was performed using electrospray ionization (ESI) with a capillary voltage of 3.0 kV, a sample cone voltage of 30 V, and detection in positive mode. The mass range detected was m / z = 100 to 1200.

[0655] The component with m / z = 564.18 separated and ionized under the above conditions was collided with argon gas in a collision cell to dissociate into product ions. The energy during the collision with argon (collision energy) was 70 eV. Figure 107 The graph shows the results of MS analysis of the dissociated product ions using time-of-flight mass spectrometry (ToF-MS).

[0656] Depend on Figure 107The results show that in 2,5mDBFP2Pm-II of one embodiment of the present invention, peaks of product ions of partial skeletons are mainly detected near m / z = 239, near m / z = 255, and near m / z = 268, a peak derived from precursor ions is mainly detected near m / z = 565, and a peak derived from dimer ions is mainly detected near m / z = 1129. In addition, Figure 107 The results show characteristics derived from 2,5mDBFP2Pm-II, and thus can be said to be important data for identifying 2,5mDBFP2Pm-II contained in the mixture.

[0657] also, Figure 38A The absorption spectrum of the toluene solution of 2,5mDBFP2Pm-II is shown. Figure 38B Its emission spectrum is shown. Figure 39A The absorption spectrum of the thin film of 2,5mDBFP2Pm-II is shown. Figure 39B The emission spectrum is shown. The absorption spectrum is measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). The solution is placed in a quartz dish, and a thin film is evaporated on a quartz substrate to make a sample for measurement. The absorption spectrum of the solution is obtained by subtracting the absorption spectrum measured by placing only toluene in the quartz dish. The absorption spectrum of the thin film is obtained by subtracting the absorption spectrum of the quartz substrate. Figures 38A to 39B In the figure, the horizontal axis represents wavelength (nm) and the vertical axis represents intensity (arbitrary unit). When measuring a toluene solution, an absorption peak was observed near 287 nm, and a peak of the emission wavelength was observed near 425 nm. In addition, when measuring a thin film, absorption peaks were observed near 205 nm, 247 nm, 280 nm, 302 nm, and 316 nm, and a peak of the emission wavelength was observed near 390 nm.

[0658] As shown in Examples 1 to 10, according to the absorption spectrum, the band gap (Bg) between the HOMO and LUMO of the organic compound containing a pyrimidine skeleton of the second compound of the present invention is wide. The organic compound has almost no absorption in the visible region and has high light transmittance, so when the organic compound is used in a light-emitting element, it is not easy to absorb the luminous energy, so that a high-efficiency element can be expected. Moreover, according to the absorption spectrum, the organic compound has a high S1 energy level, so it can be expected that the organic compound can be used as a main material of a material that emits fluorescence in the visible region. In addition, because the organic compound has a high S1 energy level, it can be expected to have a high T1 energy level. In addition, because the organic compound emits light from purple to blue, it can also be used as a light-emitting material.

[0659] Example 11

[0660] In this example, electrochemical properties (solution) were measured for the following compounds: compounds represented by structural formulas (300), (311), (314), (400), (401), (402), (412), (430), (431), and (432) produced in Examples 1 to 10 as one embodiment of an organic compound containing a pyrimidine skeleton as a second compound; and compounds represented by structural formulas (200) to (204), (210) to (213), (250), and (251) that can be used as the first compound. The chemical formulas of the materials used in this example are shown below.

[0661]

[0662]

[0663]

[0664]

[0665] Cyclic voltammetry (CV) was used as the measurement method. An electrochemical analyzer (BAS Inc., ALS model 600A or 600C) was used for the measurement. Table 1 shows the measurement results.

[0666]

[0667]

[0668] ND:No data

[0669] The data on the oxidation side (single-electron oxidation potential) shown in Table 1 corresponds to the HOMO level. Since the HOMO level of 4,6mPnP2Pm, an embodiment of the organic compound containing a pyrimidine skeleton, is deeper than the HOMO level of the iridium metal complex used as a dopant (the HOMO level of 4,6mPnP2Pm, etc. is lower than the HOMO level of the iridium metal complex), holes can be efficiently injected into these iridium metal complexes used as dopants. Furthermore, when the HOMO level of the iridium metal complex is between -6.0 eV and -5.0 eV, the iridium metal complex is more efficient at trapping holes than the organic compound containing a pyrimidine skeleton used as the second compound.

[0670] Furthermore, the data on the reduction side (single-electron reduction potential) shown in Table 1 corresponds to the LUMO energy level. Since the LUMO energy level of 4,6mPnP2Pm, an embodiment of an organic compound containing a pyrimidine skeleton, is equal to or shallower than the LUMO energy level of the phosphorescent iridium metal complex used as a dopant, and these values are close, electrons can be efficiently injected into the iridium metal complex used as a dopant. Furthermore, this allows for the production of devices with low driving voltages, without the iridium complex used as a dopant interfering with the electron transport properties of the host material, such as 4,6mPnP2Pm.

[0671] Based on the above results, the organic compound containing a pyrimidine skeleton of the present invention has a deep HOMO energy level and an appropriate LUMO energy level, and is therefore suitable for use as a host material for an iridium metal complex. In particular, it is suitable for use as an iridium metal complex containing a diazine skeleton having a LUMO energy level similar to that of the host material, specifically an iridium metal complex containing a pyrimidine skeleton.

[0672] In addition, the phosphorescent iridium metal complexes represented by structural formulas (200) to (204), (250) and (251) have a pyrimidine skeleton, and the phosphorescent iridium metal complexes represented by structural formulas (210) to (213) have a pyrazine skeleton, so the above compounds all have a diazine skeleton.

[0673] The cyclic voltammetry (CV) measurement method is as follows: Although 4,6mPnP2Pm is mentioned in the following description, other compounds can be measured using the same method.

[0674] The solution used for CV measurement consisted of dehydrated dimethylformamide (DMF, Sigma-Aldrich Inc., 99.8%, Catalog No. 22705-6) as the solvent, and tetra-n-butylammonium perchlorate (n-Bu4NClO4, Tokyo Chemical Industry Co., Ltd., Catalog No. T0836) as the supporting electrolyte, dissolved in the solvent to a concentration of 100 mmol / L. Furthermore, the target substance to be measured was dissolved in the solvent to a concentration of 2 mmol / L. A platinum electrode (BAS Inc., PTE platinum electrode) was used as the working electrode, a platinum electrode (BAS Inc., Pt counter electrode for VC-3 (5 cm)) was used as the auxiliary electrode, and an Ag / Ag+ electrode (BAS Inc., RE7 non-aqueous solvent-based reference electrode) was used as the reference electrode. The CV measurement was performed at room temperature (20° C. to 25° C.) and the scanning rate during the CV measurement was uniformly set to 0.1 V / sec.

[0675] (Calculation of the potential energy of the reference electrode relative to the vacuum level)

[0676] First, calculate the potential energy (eV) relative to the vacuum level of the reference electrode (Ag / Ag+ electrode) used in this example. Specifically, calculate the Fermi level of the Ag / Ag+ electrode. It is known that the redox potential of ferrocene in methanol relative to the standard hydrogen electrode is +0.610 [V vs. SHE] (reference: Christian R. Goldsmith et al., J. Am. Chem. Soc., Vol. 124, No. 1, pp. 83-96, 2002).

[0677] On the other hand, the redox potential of ferrocene in methanol was calculated using the reference electrode used in this example, and the result was +0.11 V [vs. Ag / Ag+]. Therefore, it was found that the potential energy of the reference electrode used in this example was 0.50 [eV] lower than that of the standard hydrogen electrode.

[0678] The potential energy of the standard hydrogen electrode relative to the vacuum level is known to be -4.44 eV (reference: Toshihiro Ohnishi, Tamami Koyama. High Molecular EL Material., Kyoritsu Shuppan, pp. 64-67). Therefore, the potential energy of the reference electrode used in this example relative to the vacuum level is calculated to be -4.44-0.50=-4.94 [eV].

[0679] In the measurement of the oxidation reaction characteristics of the compound of this example, the potential of the working electrode relative to the reference electrode was swept from about 0.3 V to about 1.5 V and then from about 1.5 V to about 0.3 V.

[0680] Next, the calculation of the HOMO energy level of the target substance by CV measurement is described in detail. Calculation of the oxidation peak potential (between the neutral state and the oxidation side) E pa [V] and reduction peak potential (from the oxidized side to the neutral state) E pc [V]. Thus, the half-wave potential (at E pa With E pc The potential in the middle of pa +E pc ) / 2[V]. This shows that the compound of the example was oxidized by electric energy having a half-wave potential value [V vs. Ag / Ag+], which corresponds to the HOMO level.

[0681] In measuring the reduction reaction characteristics of the compound of this example, the potential of the working electrode relative to the reference electrode was swept from approximately -1.5 V to approximately -2.2 V, and then from approximately -2.2 V to approximately -1.5 V.

[0682] Next, the calculation of the LUMO energy level of the target substance based on the CV measurement is described in detail. The reduction peak potential (between the neutral state and the reduction side) E is calculated. pa [V] and oxidation peak potential (from the reduction side to the neutral state) E pc [V]. Thus, the half-wave potential (at E pa With E pc The potential in the middle of pa +E pc ) / 2[V]. This shows that the compound of the example is reduced by electric energy of the value of the half-wave potential [V vs. Ag / Ag+], which corresponds to the LUMO level.

[0683] Example 12

[0684] In this example, a light-emitting element 1 was evaluated using a first compound, which is a phosphorescent iridium metal complex containing a pyrimidine skeleton, and a second compound, which is an organic compound containing a pyrimidine skeleton represented by structural formula (300) as described in Embodiment 1 and Example 1, as light-emitting substances. The chemical formulas of the materials used in this example are shown below.

[0685]

[0686] Reference Figure 40 The light emitting element 1 will be described. A method for manufacturing the light emitting element 1 of this embodiment will be described below.

[0687] (Light-emitting element 1)

[0688] First, an indium oxide-tin oxide compound (ITO-SiO2, hereinafter referred to as ITSO) containing silicon or silicon oxide is formed on a substrate 1100 by sputtering, thereby forming a first electrode 1101. The target material composition ratio used is In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 1101 is set to 110 nm, and its electrode area is set to 2 mm × 2 mm. Here, the first electrode 1101 serves as the anode of the light-emitting element.

[0689] Next, as pretreatment for forming a light-emitting element over the substrate 1100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0690] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking was performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 1100 was cooled for about 30 minutes.

[0691] Next, the substrate 1100 having the first electrode 1101 formed thereon is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface having the first electrode 1101 formed thereon faces downward, and the pressure is reduced to 10°C. -4 Pa, 1,3,5-tris(dibenzothiophen-4-yl)benzene (DBT3P-II) and molybdenum oxide were co-evaporated on the first electrode 1101 to form a hole injection layer 1111. The thickness of the hole injection layer 1111 was set to 40 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (DBT3P-II:molybdenum oxide). Co-evaporation refers to a method in which deposition is performed simultaneously from multiple evaporation sources in a single processing chamber.

[0692] Next, 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine (abbreviated as BPAFLP) was formed to a thickness of 20 nm on the hole-injection layer 1111 , thereby forming the hole-transport layer 1112 .

[0693] Furthermore, a first light-emitting layer 1113a was formed on the hole-transporting layer 1112 by co-evaporation of 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as 4,6mPnP2Pm), 4-phenyl-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as PCBA1BP), and (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidino)iridium(III) (abbreviated as [Ir(tBuppm)2(acac)]) synthesized in Example 1. The weight ratio of 4,6mPnP2Pm, PCBA1BP, and [Ir(tBuppm)2(acac)] was adjusted to 0.7:0.3:0.05 (=4,6mPnP2Pm:PCBA1BP:[Ir(tBuppm)2(acac)]). In addition, the thickness of the first light-emitting layer 1113a was set to 15 nm.

[0694] Next, a second light-emitting layer 1113b was formed on the first light-emitting layer 1113a by co-evaporating 4,6mPnP2Pm, PCBA1BP, and [Ir(tBuppm)2(acac)] onto the first light-emitting layer 1113a. The weight ratio of 4,6mPnP2Pm, PCBA1BP, and [Ir(tBuppm)2(acac)] was adjusted to 0.8:0.2:0.05 (4,6mPnP2Pm:PCBA1BP:[Ir(tBuppm)2(acac)]). The thickness of the second light-emitting layer 1113b was 25 nm.

[0695] Next, 4,6mPnP2Pm was formed to a thickness of 10 nm over the second light-emitting layer 1113b, thereby forming a first electron-transport layer 1114a.

[0696] Next, bathophenanthroline (abbreviated as BPhen) was formed to a thickness of 20 nm on the first electron-transport layer 1114 a , thereby forming a second electron-transport layer 1114 b .

[0697] Furthermore, a lithium fluoride (LiF) film was formed to a thickness of 1 nm by vapor deposition over the second electron-transport layer 1114 b , thereby forming the electron-injection layer 1115 .

[0698] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 1103 functioning as a cathode, thereby manufacturing the light-emitting element 1 of this example.

[0699] Table 2 shows the device structure of the light-emitting device 1 obtained through the above steps.

[0700]

[0701] In a nitrogen atmosphere glove box, the light-emitting element 1 was sealed (a sealing material was applied around the element and heat treated at 80°C for 1 hour during sealing) to prevent the element from being exposed to the atmosphere. The operating characteristics of the light-emitting element 1 were then measured. The measurements were performed at room temperature (in an atmosphere maintained at 25°C).

[0702] Figure 41 The current density-luminance characteristics of the light-emitting element 1 are shown. Figure 41 The horizontal axis represents the current density (mA / cm 2 ), while the vertical axis represents brightness (cd / m 2 ).in addition, Figure 42 The voltage-luminance characteristics of the light-emitting element 1 are shown. Figure 42 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents brightness (cd / m 2 ).in addition, Figure 43The luminance-current efficiency characteristics of the light-emitting element 1 are shown. Figure 43 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents the current efficiency (cd / A). Figure 44 The voltage-current characteristics of the light-emitting element 1 are shown. Figure 44 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents current (mA). Figure 45 The luminance-chromaticity coordinate characteristics of the light emitting element 1 are shown. Figure 45 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents chromaticity (x coordinate and y coordinate). Figure 46 The luminance-power efficiency characteristics of the light-emitting element 1 are shown. Figure 46 In the figure, the horizontal axis represents the brightness (cd / m 2 ), while the vertical axis represents power efficiency (lm / W).

[0703] In addition, Table 3 shows that the luminance of the light emitting element 1 is about 1000 cd / m 2 The voltage (V), current density (mA / cm 2 ), CIE chromaticity coordinates (x, y), brightness (cd / m 2 ), current efficiency (cd / A) and external quantum efficiency (%).

[0704] [Table 3]

[0705]

[0706] Figure 47 The current density of the light-emitting element 1 is 2.5 mA / cm 2 The emission spectrum of Figure 47 As shown, the emission spectrum of Light-emitting Element 1 has a peak at 547 nm.

[0707] In addition, as shown in Table 3, the luminance of the light-emitting element 1 is 1300 cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.43, 0.56). This shows that luminescence originating from the dopant is obtained.

[0708] As shown above, the light-emitting element 1 according to one embodiment of the present invention, which uses a phosphorescent iridium metal complex containing a pyrimidine skeleton as the first compound and an organic compound containing a pyrimidine skeleton as the second compound as the light-emitting substance, can efficiently emit light in the green wavelength region. Furthermore, 4,6mPnP2Pm has a higher T1 level than green light, making it suitable for use as a host material for light-emitting materials that emit green light or light with a wavelength longer than green.

[0709] In addition, according to Figure 41 and Figure 42 It can be seen that the light emitting element 1 is a low driving voltage and low power consumption element. Figure 43 and Figure 46 It can be seen that the light emitting element 1 is a high efficiency element. Figure 45 It can be seen that the light-emitting element 1 is an element with excellent carrier balance at various luminance levels.

[0710] Next, the light emitting element 1 was evaluated by a reliability test. Figure 48 and Figure 49 The results of the reliability test are shown.

[0711] In the reliability test, the initial brightness was set to 5000cd / m 2 The light emitting element 1 is driven under the condition of constant current density. Figure 48 The results are shown in FIG. 1 . The horizontal axis represents the driving time (h) of the element, and the vertical axis represents the normalized brightness (%) when the initial brightness is 100%. Figure 48 It can be seen that after about 290 hours, the normalized luminance of the light-emitting element 1 drops to below 70%.

[0712] according to Figure 48 It can be seen that the light emitting element 1 has a long service life.

[0713] The above results indicate that the light-emitting element 1 of one embodiment of the present invention, which uses a phosphorescent iridium metal complex containing pyrimidine as the first compound and an organic compound containing a pyrimidine skeleton as the second compound as light-emitting substances, is a light-emitting element with high efficiency, low driving voltage, low power consumption, and long service life.

[0714] Next, in the reliability test, the initial brightness was set to 5000 cd / m 2 The temporal change in the voltage of the light-emitting element 1 was measured under the condition of a constant current density. Figure 49 The results are shown in FIG. The horizontal axis represents the driving time (h) of the element, and the vertical axis represents the voltage (V). Figure 49 It can be seen that the degree of temporal increase in the voltage of the light emitting element 1 is small.

[0715] Example 13

[0716] In this example, light-emitting element 2 and light-emitting element 3 using the organic compound represented by structural formula (400) synthesized in Example 4, which is one embodiment of the present invention, were evaluated. The chemical formula of the material of light-emitting element 2 used in this example is shown below.

[0717]

[0718] Reference Figure 50AThe light emitting element 2 will be described below. A method for manufacturing the light emitting element 2 of this embodiment will be described below.

[0719] (Light-emitting element 2)

[0720] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0721] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0722] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0723] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, 1,3,5-tris(dibenzothiophene-4-yl)benzene (DBT3P-II) and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 40 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (DBT3P-II:molybdenum oxide). Co-evaporation refers to a deposition method in which deposition is performed simultaneously from multiple evaporation sources in a single processing chamber.

[0724] Next, 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine (abbreviated as BPAFLP) was formed to a thickness of 20 nm on the hole-injection layer 2111 , thereby forming the hole-transport layer 2112 .

[0725] Furthermore, a first light-emitting layer 2113a was formed on the hole-transporting layer 2112 by co-evaporation of 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II), 4-phenyl-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as PCBA1BP), and (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidino)iridium(III) (abbreviated as [Ir(tBuppm)2(acac)]) synthesized in Example 4. The weight ratio of 4,6mDBTP2Pm-II, PCBA1BP, and [Ir(tBuppm)2(acac)] was adjusted to 0.7:0.3:0.05 (4,6mDBTP2Pm-II:PCBA1BP:[Ir(tBuppm)2(acac)]). In addition, the thickness of the first light-emitting layer 2113a was set to 15 nm.

[0726] Next, a second light-emitting layer 2113b was formed on the first light-emitting layer 2113a by co-evaporating 4,6mDBTP2Pm-II, PCBA1BP, and [Ir(tBuppm)2(acac)]. The weight ratio of 4,6mDBTP2Pm-II, PCBA1BP, and [Ir(tBuppm)2(acac)] was adjusted to 0.8:0.2:0.05 (4,6mDBTP2Pm-II:PCBA1BP:[Ir(tBuppm)2(acac)]). The thickness of the second light-emitting layer 2113b was 25 nm.

[0727] Next, 4,6mDBTP2Pm-II was formed to a thickness of 10 nm over the second light-emitting layer 2113b, thereby forming a first electron-transport layer 2114a.

[0728] Next, bathophenanthroline (abbreviated as BPhen) was formed to a thickness of 20 nm on the first electron-transporting layer 2114 a , thereby forming a second electron-transporting layer 2114 b .

[0729] Furthermore, lithium fluoride (LiF) was deposited to a thickness of 1 nm on the second electron-transport layer 2114 b , thereby forming the electron-injection layer 2115 .

[0730] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 2 of this example.

[0731] Table 4 shows the device structure of the light-emitting device 2 obtained through the above steps.

[0732]

[0733] The chemical formula of the material of the light-emitting element 3 used in this example is shown below.

[0734]

[0735] Reference Figure 50B The light emitting element 3 will be described below. A method for manufacturing the light emitting element 3 of this embodiment will be described below.

[0736] (Light-emitting element 3)

[0737] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0738] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0739] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0740] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, 4,4'-bis(N-carbazolyl)biphenyl (CBP) and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 60 nm, and the weight ratio of CBP to molybdenum oxide was adjusted to 4:2 (=CBP:molybdenum oxide). Co-evaporation refers to an evaporation method in which evaporation is performed simultaneously from multiple evaporation sources in a single processing chamber.

[0741] Next, 1,3-bis(N-carbazolyl)benzene (abbreviated as mCP) was formed to a thickness of 20 nm on the hole-injection layer 2111 , thereby forming the hole-transport layer 2112 .

[0742] Furthermore, a first light-emitting layer 2113a was formed on the hole-transporting layer 2112 by co-evaporation of 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II), 9-phenyl-9H-3-(9-phenyl-9H-carbazol-3-yl)carbazole (abbreviated as PCCP), and tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviated as [Ir(Mptz1-mp)3]) synthesized in Example 4. The weight ratio of 4,6mDBTP2Pm-II, PCCP, and [Ir(Mptz1-mp)3] was adjusted to 1:0.3:0.08 (=4,6mDBTP2Pm-II:PCCP:[Ir(Mptz1-mp)3]). In addition, the thickness of the first light-emitting layer 2113a was set to 30 nm.

[0743] Next, a second light-emitting layer 2113b was formed on the first light-emitting layer 2113a by co-evaporating 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (mDBTBIm-II) and [Ir(Mptz1-mp)3] onto the first light-emitting layer 2113a. The weight ratio of mDBTBIm-II to [Ir(Mptz1-mp)3] was adjusted to 1:0.08 (=mDBTBIm-II:[Ir(Mptz1-mp)3]). The thickness of the second light-emitting layer 2113b was set to 10 nm.

[0744] Next, bathophenanthroline (abbreviated as BPhen) was formed to a thickness of 15 nm over the second light-emitting layer 2113 b , thereby forming the electron-transport layer 2114 .

[0745] Furthermore, lithium fluoride (LiF) was deposited to a thickness of 1 nm on the electron-transporting layer 2114 , thereby forming the electron-injecting layer 2115 .

[0746] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 3 of this example.

[0747] Table 5 shows the device structure of the light-emitting device 3 obtained through the above steps.

[0748]

[0749] In a nitrogen atmosphere glove box, the light-emitting elements 2 and 3 manufactured through the above steps were sealed (a sealing material was applied around the element and heat treated at 80°C for 1 hour during sealing) so as not to expose them to the atmosphere. The operating characteristics of the light-emitting elements 2 and 3 were then measured. The measurements were performed at room temperature (in an atmosphere maintained at 25°C).

[0750] Figure 51 and Figure 58 The current density-luminance characteristics of light-emitting element 2 and light-emitting element 3 are shown respectively. Figure 51 and Figure 58 The horizontal axis represents the current density (mA / cm 2 ), while the vertical axis represents brightness (cd / m 2 ).in addition, Figure 52 and Figure 59 The voltage-luminance characteristics of light-emitting element 2 and light-emitting element 3 are shown respectively. Figure 52 and Figure 59 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents brightness (cd / m 2 ).in addition, Figure 53 and Figure 60 The luminance-current efficiency characteristics of light-emitting element 2 and light-emitting element 3 are shown respectively. Figure 53 and Figure 60 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents the current efficiency (cd / A). Figure 54 and Figure 61 The voltage-current characteristics of light emitting element 2 and light emitting element 3 are shown respectively. Figure 54 and Figure 61 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents current (mA). Figure 55 and Figure 62 The luminance-chromaticity coordinate characteristics of light emitting element 2 and light emitting element 3 are shown respectively. Figure 55 and Figure 62 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents chromaticity (x coordinate and y coordinate). Figure 56 and Figure 63 The brightness-power efficiency characteristics of light-emitting element 2 and light-emitting element 3 are shown respectively. Figure 56 and Figure 63 In the figure, the horizontal axis represents the brightness (cd / m 2 ), while the vertical axis represents power efficiency (lm / W).

[0751] according to Figure 56 and Figure 63 It can be seen that light emitting element 2 and light emitting element 3 are high efficiency elements. Figure 55 and Figure 62 It can be seen that the light emitting element 2 and the light emitting element 3 are elements with good carrier balance at each brightness. Figure 54 and Figure 61 It can be seen that the light-emitting element 2 and the light-emitting element 3 are elements having a low driving voltage and low power consumption.

[0752] In addition, Table 6 shows that the luminance of light emitting element 2 and light emitting element 3 is about 1000 cd / m 2 The voltage (V), current density (mA / cm 2 ), CIE chromaticity coordinates (x, y), brightness (cd / m 2 ), current efficiency (cd / A) and external quantum efficiency (%).

[0753] [Table 6]

[0754]

[0755] in addition, Figure 57 and Figure 64 The current density of light emitting element 2 and light emitting element 3 is 2.5 mA / cm 2 The emission spectrum of Figure 57 and Figure 64 As shown, the emission spectra of Light-Emitting Element 2 and Light-Emitting Element 3 have peaks at 548 nm and 472 nm, respectively.

[0756] In addition, as shown in Table 6, the luminance of light emitting element 2 is 723 cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.43, 0.56). In addition, the luminance of the light-emitting element 3 is 735 cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.20, 0.35). This shows that both Light-Emitting Element 2 and Light-Emitting Element 3 emit light originating from the dopant.

[0757] As can be seen from the above, Light-Emitting Element 2 according to one embodiment of the present invention can efficiently emit light in the yellow wavelength region. Furthermore, Light-Emitting Element 3 according to one embodiment of the present invention can efficiently emit light in the blue wavelength region. In other words, 4,6mDBTP2Pm-II has a higher T1 level than blue light, making it suitable for use as a host material for light-emitting materials emitting light in the visible region (blue to red).

[0758] Example 14

[0759] In this example, light-emitting element 4, light-emitting element 5, light-emitting element 6 using an organic compound represented by structural formula (400) synthesized in Example 4 according to one embodiment of the present invention and light-emitting element 7 using 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviated as: 4,6CzP2Pm) were evaluated.

[0760] First, the chemical formula of the material used for the light-emitting element 4 of this embodiment is shown.

[0761]

[0762] Reference Figure 50A The light emitting element 4 will be described below. A method for manufacturing the light emitting element 4 of this embodiment will be described below.

[0763] (Light-emitting element 4)

[0764] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0765] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0766] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0767] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, DBT3P-II and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 40 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (=DBT3P-II:molybdenum oxide).

[0768] Next, BPAFLP was formed to a thickness of 20 nm over the hole-injection layer 2111 , thereby forming the hole-transport layer 2112 .

[0769] Furthermore, 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II), 4-4′-di(1-naphthyl)-4″-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as PCBNBB), and (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidino)iridium(III) (abbreviated as [Ir(tBuppm)2(acac)] synthesized in Example 4 were co-deposited. ), a first light-emitting layer 2113a was formed on the hole-transporting layer 2112. The weight ratio of 4,6mDBTP2Pm-II, PCBNBB, and [Ir(tBuppm)2(acac)] was adjusted to 0.5:0.5:0.05 (=4,6mDBTP2Pm-II:PCBNBB:[Ir(tBuppm)2(acac)]). The thickness of the first light-emitting layer 2113a was set to 20 nm.

[0770] Next, a second light-emitting layer 2113b was formed on the first light-emitting layer 2113a by co-evaporating 4,6mDBTP2Pm-II, PCBNBB, and [Ir(tBuppm)2(acac)]. The weight ratio of 4,6mDBTP2Pm-II, PCBNBB, and [Ir(tBuppm)2(acac)] was adjusted to 0.8:0.2:0.05 (4,6mDBTP2Pm-II:PCBNBB:[Ir(tBuppm)2(acac)]). The thickness of the second light-emitting layer 2113b was 20 nm.

[0771] Next, 4,6mDBTP2Pm-II was formed to a thickness of 10 nm over the second light-emitting layer 2113b, thereby forming a first electron-transport layer 2114a.

[0772] Next, BPhen was formed to a thickness of 20 nm over the first electron-transport layer 2114 a , thereby forming a second electron-transport layer 2114 b .

[0773] Furthermore, lithium fluoride (LiF) was deposited to a thickness of 1 nm on the second electron-transport layer 2114 b , thereby forming the electron-injection layer 2115 .

[0774] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 4 of this example.

[0775] Table 7 shows the device structure of the light-emitting device 4 obtained through the above steps.

[0776]

[0777] Next, the chemical formula of the material used for the light-emitting element 5 of this embodiment is shown below.

[0778]

[0779] Reference Figure 50C Description of the light emitting element 5. Hereinafter, a method for manufacturing the light emitting element 5 of this embodiment will be described.

[0780] (Light-emitting element 5)

[0781] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0782] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0783] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0784] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, DBT3P-II and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 40 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (=DBT3P-II:molybdenum oxide).

[0785] Next, 9-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]-9H-carbazole (abbreviated as mCzFLP) and PCCP were co-evaporated on the hole-injection layer 2111 to form a hole-transport layer 2112. The thickness of the hole-transport layer 2112 was set to 20 nm, and the weight ratio of mCzFLP to PCCP was adjusted to 1:1 (=mCzFLP:PCCP).

[0786] Furthermore, 4,6mDBTP2Pm-II, PCCP and tris(2-phenylpyridine-N,C 2′ ) iridium (III) (abbreviated as [Ir(ppy)3]), and a light-emitting layer 2113 was formed on the hole-transporting layer 2112. The weight ratio of 4,6mDBTP2Pm-II, PCCP, and [Ir(ppy)3] was adjusted to 0.8:0.2:0.05 (=4,6mDBTP2Pm-II:PCCP:[Ir(ppy)3]). The thickness of the light-emitting layer 2113 was set to 40 nm.

[0787] Next, 4,6mDBTP2Pm-II was formed to a thickness of 10 nm over the light-emitting layer 2113, thereby forming a first electron-transport layer 2114a.

[0788] Next, BPhen was formed to a thickness of 20 nm over the first electron-transport layer 2114 a , thereby forming a second electron-transport layer 2114 b .

[0789] Furthermore, lithium fluoride (LiF) was deposited to a thickness of 1 nm on the second electron-transport layer 2114 b , thereby forming the electron-injection layer 2115 .

[0790] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 5 of this example.

[0791] Table 8 shows the device structure of the light-emitting device 5 obtained through the above steps.

[0792]

[0793] Next, the chemical formula of the material used for the light-emitting element 6 of this embodiment is shown below.

[0794]

[0795] Reference Figure 50A The light emitting element 6 will be described below. A method for manufacturing the light emitting element 6 of this embodiment will be described below.

[0796] (Light-emitting element 6)

[0797] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0798] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0799] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0800] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, DBT3P-II and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 30 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (=DBT3P-II:molybdenum oxide).

[0801] Next, BPAFLP was formed to a thickness of 20 nm over the hole-injection layer 2111 , thereby forming the hole-transport layer 2112 .

[0802] A first light-emitting layer 2113a was formed on the hole-transporting layer 2112 by co-evaporation of 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviated as 4,6mDBTP2Pm-II), PCCP, and tris[2-methyl-3-(6-tert-butyl-4-pyrimidinyl-κN3)pyridyl-κC] (abbreviated as [Ir(tBumpypm)3]) synthesized in Example 4. The weight ratio of 4,6mDBTP2Pm-II, PCCP, and [Ir(tBumpypm)3] was adjusted to 0.5:0.5:0.05 (4,6mDBTP2Pm-II:PCCP:[Ir(tBumpypm)3]. The thickness of the first light-emitting layer 2113a was 20 nm.

[0803] Next, a second light-emitting layer 2113b was formed on the first light-emitting layer 2113a by co-evaporating 4,6mDBTP2Pm-II, PCCP, and [Ir(tBumpypm)3]. The weight ratio of 4,6mDBTP2Pm-II, PCCP, and [Ir(tBumpypm)3] was adjusted to 0.8:0.2:0.05 (4,6mDBTP2Pm-II:PCCP:[Ir(tBumpypm)3]. The thickness of the second light-emitting layer 2113b was 20 nm.

[0804] Next, 4,6mDBTP2Pm-II was formed to a thickness of 10 nm over the second light-emitting layer 2113b, thereby forming a first electron-transport layer 2114a.

[0805] Next, BPhen was formed to a thickness of 15 nm over the first electron-transport layer 2114 a , thereby forming a second electron-transport layer 2114 b .

[0806] Furthermore, a lithium fluoride (LiF) film was formed to a thickness of 1 nm by vapor deposition on the second electron-transport layer 2114 b , thereby forming the electron-injection layer 2115 .

[0807] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 6 of this example.

[0808] Table 9 shows the device structure of the light-emitting device 6 obtained through the above steps.

[0809]

[0810] Next, the chemical formula of the material used for the light-emitting element 7 of this embodiment is shown below.

[0811]

[0812] Reference Figure 50A Description of the light emitting element 7. Hereinafter, a method for manufacturing the light emitting element 7 of this embodiment will be described.

[0813] (Light-emitting element 7)

[0814] First, an indium oxide-tin oxide compound (ITSO) containing silicon or silicon oxide was deposited on a substrate 2100 by sputtering to form a first electrode 2101. The target material composition ratio used was In2O3:SnO2:SiO2 = 85:10:5 [wt. %]. The thickness of the first electrode 2101 was set to 110 nm, and the electrode area was set to 2 mm × 2 mm. Here, the first electrode 2101 serves as the anode of the light-emitting element.

[0815] Next, as pretreatment for forming a light-emitting element over the substrate 2100, the substrate surface was washed with water and baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0816] Then, the substrate was placed in a vacuum evaporation device, and the pressure inside the device was reduced to 10 -4 Pa. Vacuum baking is performed at 170° C. for 30 minutes in a heating chamber within a vacuum evaporation apparatus, and then the substrate 2100 is cooled for about 30 minutes.

[0817] Next, the substrate 2100 on which the first electrode 2101 is formed is fixed on a substrate holder provided in a vacuum evaporation apparatus in such a manner that the surface on which the first electrode 2101 is formed faces downward, and the pressure is reduced to 10 -4 Pa, DBT3P-II and molybdenum oxide were co-evaporated on the first electrode 2101 to form a hole injection layer 2111. The thickness of the hole injection layer 2111 was set to 40 nm, and the weight ratio of DBT3P-II to molybdenum oxide was adjusted to 4:2 (=DBT3P-II:molybdenum oxide).

[0818] Next, mCzFLP was formed to a thickness of 20 nm on the hole injection layer 2111 , thereby forming the hole transport layer 2112 .

[0819] Furthermore, 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviated as 4,6mCzP2Pm), PCCP and bis[2-methyl-3-(6-tert-butyl-4-pyrimidinyl-κN3)pyridyl-κC](2,4-pentanedione-κ 2 A first light-emitting layer 2113a was formed on the hole-transport layer 2112 using iridium (III) (O,O′) (abbreviated as [Ir(tBumpypm)2(acac)]). The weight ratio of 4,6mCzP2Pm, PCCP, and [Ir(tBumpypm)2(acac)] was adjusted to 0.8:0.2:0.05 (4,6mCzP2Pm:PCCP:[Ir(tBumpypm)2(acac)]). The thickness of the first light-emitting layer 2113a was 20 nm.

[0820] Next, a second light-emitting layer 2113b was formed on the first light-emitting layer 2113a by co-evaporating 4,6mCzP2Pm and [Ir(tBumpypm)2(acac)]. The weight ratio of 4,6mCzP2Pm to [Ir(tBumpypm)2(acac)] was adjusted to 1:0.05 (4,6mCzP2Pm:[Ir(tBumpypm)2(acac)]). The thickness of the second light-emitting layer 2113b was 20 nm.

[0821] Next, 4,6mCzP2Pm was formed to a thickness of 10 nm over the second light-emitting layer 2113b, thereby forming a first electron-transport layer 2114a.

[0822] Next, BPhen was formed to a thickness of 20 nm over the first electron-transport layer 2114 a , thereby forming a second electron-transport layer 2114 b .

[0823] Furthermore, a lithium fluoride (LiF) film was formed to a thickness of 1 nm by vapor deposition on the second electron-transport layer 2114 b , thereby forming the electron-injection layer 2115 .

[0824] Finally, a 200-nm-thick aluminum film was formed by vapor deposition as the second electrode 2103 functioning as a cathode, thereby manufacturing the light-emitting element 7 of this example.

[0825] Table 10 shows the device structure of the light-emitting device 7 obtained through the above steps.

[0826]

[0827] In a nitrogen atmosphere glove box, each of the light-emitting elements 4 to 7 manufactured through the above steps was sealed (a sealing material was applied around the element and heat treated at 80°C for 1 hour during sealing) so as not to expose it to the atmosphere. The operating characteristics of these light-emitting elements 4 to 7 were then measured. The measurements were performed at room temperature (in an atmosphere maintained at 25°C).

[0828] Figure 65 、 Figure 72 、 Figure 79 and Figure 86 The current density-luminance characteristics of light-emitting element 4, light-emitting element 5, light-emitting element 6, and light-emitting element 7 are shown respectively. Figure 65 、 Figure 72 、 Figure 79 and Figure 86 The horizontal axis represents the current density (mA / cm 2 ), while the vertical axis represents brightness (cd / m 2 ).in addition, Figure 66、 Figure 73 、 Figure 80 and Figure 87 The voltage-luminance characteristics of light-emitting element 4, light-emitting element 5, light-emitting element 6, and light-emitting element 7 are shown respectively. Figure 66 、 Figure 73 、 Figure 80 and Figure 87 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents brightness (cd / m 2 ).in addition, Figure 67 、 Figure 74 、 Figure 81 and Figure 88 The luminance-current efficiency characteristics of light-emitting element 4, light-emitting element 5, light-emitting element 6, and light-emitting element 7 are shown respectively. Figure 67 、 Figure 74 、 Figure 81 and Figure 88 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents the current efficiency (cd / A). Figure 68 、 Figure 75 、 Figure 82 and Figure 89 The voltage-current characteristics of light emitting element 4, light emitting element 5, light emitting element 6 and light emitting element 7 are shown respectively. Figure 68 、 Figure 75 、 Figure 82 and Figure 89 In the figure, the horizontal axis represents voltage (V) and the vertical axis represents current (mA). Figure 69 、 Figure 76 、 Figure 83 and Figure 90 The luminance-chromaticity coordinate characteristics of light emitting element 4, light emitting element 5, light emitting element 6 and light emitting element 7 are shown respectively. Figure 69 、 Figure 76 、 Figure 83 and Figure 90 In the figure, the horizontal axis represents the brightness (cd / m 2 ), and the vertical axis represents chromaticity (x coordinate and y coordinate). Figure 70 、 Figure 77 、 Figure 84 and Figure 91 The brightness-power efficiency characteristics of light-emitting element 4, light-emitting element 5, light-emitting element 6, and light-emitting element 7 are shown respectively. Figure 70 、 Figure 77 、 Figure 84 and Figure 91 In the figure, the horizontal axis represents the brightness (cd / m 2 ), while the vertical axis represents power efficiency (lm / W).

[0829] according to Figure 70 、 Figure 77 、 Figure 84 and Figure 91 It can be seen that light emitting elements 4 to 7 are highly efficient elements. Figure 69 、 Figure 76 、 Figure 83 and Figure 90 It can be seen that light emitting elements 4 to 7 are elements with good carrier balance at each brightness. Figure 68 、 Figure 75 、 Figure 82 and Figure 89 It can be seen that light-emitting elements 4 to 7 are elements having low driving voltage and low power consumption.

[0830] In addition, Table 11 shows that the luminance of light emitting elements 4 to 7 is about 1000 cd / m 2 The voltage (V), current density (mA / cm 2 ), CIE chromaticity coordinates (x, y), brightness (cd / m 2 ), current efficiency (cd / A) and external quantum efficiency (%).

[0831] [Table 11]

[0832]

[0833] in addition, Figure 71 、 Figure 78 、 Figure 85 and Figure 92 The current density of light emitting element 4 to light emitting element 7 is 2.5 mA / cm 2 The emission spectrum of Figure 71 、 Figure 78 、 Figure 85 and Figure 92 As shown, the emission spectra of light-emitting element 4 to light-emitting element 7 have peaks at 548 nm, 513 nm, 493 nm, and 508 nm, respectively.

[0834] As described above, it was found that luminescence was obtained from each dopant material (iridium complex). Furthermore, since the organic compound containing a pyrimidine skeleton of the second compound of one embodiment of the present invention has a high T1 level, it was found that it can be used as a host material for a phosphorescent material that emits blue-green light or light with a wavelength longer than blue-green.

[0835] In addition, as shown in Table 11, the luminance of light emitting element 4 is 694 cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.43, 0.56). In addition, the luminance of the light emitting element 4 is 694 cd / m 2 The voltage, current density, current efficiency and external quantum efficiency were 2.7 V, 0.9 mA / cm2 , 79cd / A and 22%. In addition, the brightness of light emitting element 5 is 954cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.33, 0.62). In addition, the luminance of the light-emitting element 5 is 954 cd / m 2 The voltage, current density, current efficiency and external quantum efficiency were 3.1V, 1.4mA / cm 2 , 69cd / A and 20%. In addition, the brightness of the light emitting element 6 is 797cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.25, 0.52). In addition, the luminance of the light emitting element 6 is 797 cd / m 2 The voltage, current density, current efficiency and external quantum efficiency were 2.9 V, 1.3 mA / cm 2 , 60cd / A and 24%. In addition, the brightness of the light emitting element 7 is 810cd / m 2 The CIE chromaticity coordinates at this time are (x, y) = (0.30, 0.61). In addition, the luminance of the light-emitting element 7 is 810 cd / m 2 The voltage, current density, current efficiency and external quantum efficiency were 3.3 V, 1.1 mA / cm 2 , 77cd / A and 24%.

[0836] As described above, it is understood that the light-emitting elements 4 to 7 according to one embodiment of the present invention have characteristics of low driving voltage and good carrier balance.

[0837] Since the organic compound containing a pyrimidine skeleton of the second compound of one embodiment of the present invention has a high electron-transporting property, it is known that when it is used in the electron-transporting layer, a device with a low driving voltage can be obtained.

[0838] In addition, as shown in the description of light-emitting elements 4 to 7, when an organic compound containing a pyrimidine skeleton and a compound with a high hole-transporting property (PCBNBB or PCCP) of the second compound of one embodiment of the present invention are used in the light-emitting layer, electrons and holes can be efficiently injected into the dopant (iridium complex), thereby obtaining an element with high efficiency and low driving voltage.

[0839] In addition, as shown in the description of light-emitting element 5, when a material with high hole transport properties (PCCP) and a material with a high T1 energy level (mCzFLP) are used for the hole transport layer, holes are efficiently injected into the light-emitting layer and the excitation energy generated in the light-emitting layer can be suppressed from being transmitted to the hole transport layer, thereby obtaining an element with lower driving voltage and higher efficiency.

[0840] Next, the light-emitting elements 4 and 5 were evaluated by reliability tests. Figures 93 to 96 The results of the reliability test are shown.

[0841] In the reliability test, the initial brightness was set to 5000cd / m 2 The light-emitting element 4 and the light-emitting element 5 are driven under the condition of constant current density. Figure 93 and Figure 95 The results are shown in FIG. 1 . The horizontal axis represents the driving time (h) of the element, and the vertical axis represents the normalized brightness (%) when the initial brightness is 100%. Figure 93 It can be seen that after about 300 hours, the normalized brightness of the light emitting element 4 decreases to 87%. Figure 95 It can be seen that after about 420 hours, the normalized brightness of the light-emitting element 5 decreases to 83%.

[0842] Next, in the reliability test, the initial brightness was set to 5000 cd / m 2 The temporal change in voltage of Light-Emitting Element 4 and Light-Emitting Element 5 was measured under the condition of constant current density. Figure 94 and Figure 96 The results are shown in FIG. The horizontal axis represents the driving time (h) of the element, and the vertical axis represents the voltage (V). Figure 94 and Figure 96 It can be seen that the degree of temporal increase in the voltage of the light-emitting element 4 and the light-emitting element 5 is small.

[0843] As described above, it is understood that the light-emitting element 4 and the light-emitting element 5 have long service lives.

[0844] (Reference Example 1)

[0845] The synthesis method of (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinyl)iridium(III) (abbreviated as [Ir(tBuppm)2(acac)]) used in Examples 12 and 13 will be described in detail. The structure of [Ir(tBuppm)2(acac)] is shown below.

[0846]

[0847] Step 1: Synthesis of 4-tert-butyl-6-phenylpyrimidine (abbreviated as HtBuppm)

[0848] First, 22.5 g of 4,4-dimethyl-1-pentylbenzene-1,3-dione and 50 g of formamide were placed in an eggplant-shaped flask equipped with a reflux tube, and the air inside the flask was replaced with nitrogen. The reaction vessel was heated to reflux the reaction solution for 5 hours. Then, the solution was injected into an aqueous sodium hydroxide solution, and the organic layer was extracted with dichloromethane. The obtained organic layer was washed with water and saturated brine, and dried over magnesium sulfate. The dried solution was filtered. The solvent of the solution was distilled off, and the obtained residue was purified by silica gel column chromatography using hexane: ethyl acetate = 10: 1 (volume ratio) as a developing solvent. As a result, the pyrimidine derivative HtBuppm (colorless oil, yield 14%) was obtained. The following (M-1) shows the synthesis scheme of step 1.

[0849]

[0850] Step 2: Synthesis of di-μ-chloro-bis[bis(6-tert-butyl-4-phenylpyrimidinyl)iridium(III)] (abbreviated as [Ir(tBuppm)2Cl]2)

[0851] Next, in an eggplant-shaped flask equipped with a reflux tube, 15 mL of 2-ethoxyethanol, 5 mL of water, 1.49 g of HtBuppm obtained in the above-mentioned step 1, and 1.04 g of iridium chloride hydrate (IrCl 3 · H 2 O) were added and the air was replaced with argon. The reaction was then carried out by irradiating with microwaves (2.45 GHz, 100 W) for 1 hour. After distillation and removing the solvent of the solution, the resulting residue was filtered with ethanol and washed to obtain a binuclear complex [Ir(tBuppm) 2 Cl] 2 (yellow-green powder, 73% yield). The following (M-2) shows the synthesis scheme of step 2.

[0852]

[0853] Step 3: Synthesis of (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviated as [Ir(tBuppm)2(acac)])

[0854] Furthermore, in an eggplant-shaped flask equipped with a reflux tube, 40 mL of 2-ethoxyethanol, 1.61 g of the binuclear complex [Ir(tBuppm)2Cl]2 obtained in step 2 above, 0.36 g of acetylacetone, and 1.27 g of sodium carbonate were placed, and the air inside the flask was replaced with argon. The reaction was then carried out by irradiation with microwaves (2.45 GHz, 120 W) for 1 hour. The solvent was removed by distillation, and the resulting residue was filtered using ethanol, and then washed with water and ethanol. The solid was dissolved in dichloromethane and filtered through a filter aid consisting of diatomaceous earth (Wako Pure Chemical Industries, Ltd., catalog number: 531-16855), alumina, and diatomaceous earth. The solid obtained by distilling the solvent off was recrystallized using a mixed solvent of dichloromethane and hexane to obtain the target yellow powder (yield 68%). The following (M-3) shows the synthesis scheme of step 3.

[0855]

[0856] Using nuclear magnetic resonance spectroscopy ( 1 The yellow powder obtained in the above step 3 was measured by H NMR. The measurement data are shown below. The measurement results show that [Ir(tBuppm)2(acac)] was obtained.

[0857] The following shows the obtained material 1 H NMR data.

[0858] 1 H NMR. δ (CDCl3): 1.50 (s, 18H), 1.79 (s, 6H), 5.26 (s, 1H), 6.33 (d, 2H), 6.77 (t, 2H), 6.85 (t, 2H), 7.70 (d, 2H), 7.76 (s, 2H), 9.02 (s, 2H).

[0859] (Reference Example 2)

[0860] The synthesis method of tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviated as [Ir(Mptz1-mp)3]) used in Example 13 will be described in detail. The structure of [Ir(Mptz1-mp)3] is shown below.

[0861]

[0862] 《Step 1: Synthesis of N-(1-ethoxyvinyl)benzamide》

[0863] First, in a 500mL three-necked flask, 15.5g ethyl acetimidate hydrochloride, 150mL toluene, 31.9g triethylamine (Et3N) were placed, and stirred at room temperature for 10 minutes. A mixed solvent of 50mL of 17.7g benzoyl chloride and 30mL toluene was added dropwise to the mixture using a dropping funnel, and stirred at room temperature for 24 hours. After a predetermined time, the reaction mixture was filtered with suction, and the solid was washed with toluene. The filtrate obtained was concentrated to obtain N-(1-ethoxyvinyl) benzamide (red oil, 82% yield). The following (N-1) illustrates the synthesis scheme of step 1.

[0864]

[0865] Step 2: Synthesis of 3-methyl-1(2-methylphenyl)-5-phenyl-1H-1,2,4-triazole (abbreviated as HMptz1-mp)

[0866] Next, in a 300 mL eggplant-shaped flask, 8.68 g of o-tolylhydrazine hydrochloride, 100 mL of carbon tetrachloride, and 35 mL of triethylamine (Et3N) were placed and stirred at room temperature for 1 hour. After a predetermined time, 8.72 g of N-(1-ethoxyvinyl)benzamide obtained in step 1 above was added to the mixture and stirred at room temperature for 24 hours. After a predetermined time, water was added to the mixture and the aqueous layer was extracted with chloroform. The organic layer was washed with saturated brine and dried with anhydrous magnesium sulfate. The resulting mixture was naturally filtered and the filtrate was concentrated to obtain an oil. Dichloromethane was used as a developing solvent. The resulting fraction was concentrated to obtain 3-methyl-1(2-methylphenyl)-5-phenyl-1H-1,2,4-triazole (abbreviated as: HMptz1-mp) (orange oil, yield 84%). The following (N-2) shows the synthesis scheme of step 2.

[0867]

[0868] Step 3: Synthesis of tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviated as [Ir(Mptz1-mp)3])

[0869] Next, 2.71 g of the ligand HMptzl-mp obtained in step 2 above and 1.06 g of tris(acetylacetonate)iridium(III) were placed in a reaction vessel equipped with a three-way stopcock. The air in the reaction vessel was replaced with argon, and the reaction was carried out by heating at 250°C for 48 hours. The reaction mixture was dissolved in dichloromethane and purified by silica gel column chromatography. As a developing solvent, dichloromethane was first used, and then a mixed solvent of dichloromethane:ethyl acetate = 10:1 (v / v). The obtained fraction was concentrated to obtain a solid. The solid was washed with ethyl acetate and then recrystallized with a mixed solvent of dichloromethane and ethyl acetate to obtain an organometallic complex [Ir(Mptz1-mp)3] (yellow powder, yield 35%) of one embodiment of the present invention. The following (N-3) shows the synthesis scheme of step 3.

[0870]

[0871] Using nuclear magnetic resonance spectroscopy ( 1 H-NMR) was measured on the yellow powder obtained in the above step 3. The measurement results showed that [Ir(Mptz1-mp)3] was obtained.

[0872] The following shows the obtained material 1 H NMR data.

[0873] 1 H NMR. δ (CDCl3): 1.94-2.21 (m, 18H), 6.47-6.76 (m, 12H), 7.29-7.52 (m, 12H).

[0874] Reference Example 3

[0875] The synthesis method of tris[2-methyl-3-(6-tert-butyl-4-pyrimidinyl-κN3)pyridine-κC]iridium(III) (abbreviated as [Ir(tBumpypm)3]) used in Example 14 will be described. The structure of [Ir(tBumpypm)3] is shown below.

[0876]

[0877] 《Step 1: Synthesis of 4-hydroxy-6-tert-butylpyrimidine》

[0878] First, 7.2 g of formamidine acetate, 7.5 g of sodium methoxide and 70 mL of methanol were added to a 100 mL three-necked flask, and 10 g of methyl 4,4-dimethyloxopentanoate was added to the mixed solution and stirred at room temperature for 24 hours. After a predetermined time, a mixed solution of 17 mL of water and 7.2 mL of acetic acid was added to the mixed solution and stirred at room temperature. The mixture was concentrated, the obtained residue was dissolved in water, and extracted with ethyl acetate. The obtained extract was washed with saturated brine, and anhydrous magnesium sulfate was added to the organic layer for drying. The obtained mixture was naturally filtered, and the filtrate was concentrated to obtain a solid. The solid was washed with ethyl acetate to obtain 4-hydroxy-6-tert-butylpyrimidine (white solid, yield 49%). The following (P-1) shows the synthesis scheme of step 1.

[0879]

[0880] 《Step 2: Synthesis of 4-chloro-6-tert-butylpyrimidine》

[0881] Next, 4.7 g of 4-hydroxy-6-tert-butylpyrimidine obtained by the above step 1 and 14 mL of phosphorus oxychloride were added to a 50 mL three-necked flask and heated under reflux for 1.5 hours. After reflux, phosphorus oxychloride was distilled off under reduced pressure. The obtained residue was dissolved in dichloromethane and washed with water and saturated sodium bicarbonate aqueous solution. Anhydrous magnesium sulfate was added to the obtained organic layer for drying. Th...

Claims

1. A light-emitting device, comprising: a first electrode; a light-emitting layer on the first electrode, the light-emitting layer comprising a first compound and a second compound; as well as a second electrode on the light-emitting layer, Wherein, the first compound is a phosphorescent iridium metal complex having a diazine skeleton, The second compound is an organic compound having a pyrimidine skeleton, Each of the first compound and the second compound has a LUMO level of -3.5 eV or more and -2.5 eV or less, and The first compound has a HOMO energy level of -6.0 eV or more and -5.0 eV or less.

2. The light emitting device according to claim 1, wherein The diazine skeleton is a pyrimidine skeleton.

3. The light emitting device according to claim 1, wherein The first compound has a LUMO energy level of -3.09 eV or more and -2.73 eV or less in cyclic voltammetry.

4. A light-emitting device comprising: a first electrode; a light-emitting layer on the first electrode, the light-emitting layer comprising a first compound and a second compound; as well as a second electrode on the light-emitting layer, wherein the first compound is a phosphorescent iridium metal complex having one of a quinoline skeleton and a quinoxaline skeleton, The second compound is an organic compound having a pyrimidine skeleton, and Each of the first compound and the second compound has a LUMO level of −3.5 eV or more and −2.5 eV or less.

5. The light emitting device according to claim 4, wherein One of the quinoline skeleton and the quinoxaline skeleton forms a coordinate bond with the iridium atom in the first compound. The light emitting device according to claim 4 , wherein: One of the quinoline skeleton and the quinoxaline skeleton is a quinoline skeleton.

7. The light emitting device according to claim 6, wherein: The first compound has a quinoline ring and a benzene ring, and the quinoline ring and the benzene ring are coordinated to an iridium atom.

8. The light emitting device according to claim 4, wherein One of the quinoline skeleton and the quinoxaline skeleton is a quinoxaline skeleton.

9. The light emitting device according to claim 4, wherein: The first compound has a HOMO energy level of -6.0 eV or more and -5.0 eV or less.

10. The light emitting device according to claim 1 or 8, wherein: The second compound has a HOMO energy level of -6.0 eV or less.

11. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound comprises a m-phenylene group.

12. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound has a LUMO energy level of -2.83 eV or more and -2.66 eV or less.

13. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound is a fused aromatic compound.

14. The light emitting device according to claim 13, wherein: The fused aromatic compound is a fused heteroaromatic compound.

15. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound has a LUMO orbital in the pyrimidine skeleton.

16. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound further comprises a carbazole skeleton.

17. The light emitting device according to any one of claims 1, 4, 6 and 7, wherein: The second compound includes any one of a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

18. An electronic device comprising the light emitting device according to claim 1 or 4.

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