Heterocyclic compound, light-emitting element, light-emitting device, electronic device, and lighting device

Abstract

A novel heterocyclic compound is provided. In particular, a novel heterocyclic compound which can improve element characteristics of a light-emitting element is provided. A heterocyclic compound represented by the following general formula (Gl), in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzobisbenzofuranyl group are bonded via a substituted or unsubstituted arylene group. In the general formula, DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzobisbenzofuranyl group. When the arylene group represented by Ar 1 and Ar 2 has a substituent, the substituents can also be bonded to each other to form a ring.

Description

[0001] This application is a divisional application of the patent application with the application date of June 24, 2016, the application number of 201610472256.1, and the invention title of "Heterocyclic Compound, Light Emitting Element, Light Emitting Device, Electronic Device, and Illumination Device". TECHNICAL FIELD

[0002] One embodiment of the present application relates to an object, a method, or a manufacturing method. In addition, the present application relates to a process, a machine, a manufacture, or a composition of matter. In particular, one embodiment of the present application relates to a semiconductor device, a light emitting device, a display device, a lighting device, a light emitting element, and a driving method or a manufacturing method thereof. Furthermore, one embodiment of the present application relates to a heterocyclic compound and a novel synthesis method thereof. Furthermore, one embodiment of the present application relates to a light emitting element, a light emitting device, an electronic device, and an illumination device using the above heterocyclic compound. Note that one embodiment of the present application is not limited to the technical field. BACKGROUND

[0003] A light emitting element using an organic compound as a light emitting body is expected to be applied to a next-generation flat panel display because of thinness, lightweight, high-speed responsiveness, direct-current low-voltage driving, and the like. In particular, a display device in which light emitting elements are arranged in a matrix has advantages of a wide viewing angle and excellent visibility over a liquid crystal display device.

[0004] The light emitting mechanism of a light emitting element is considered to be as follows: an electron injected from a cathode and a hole injected from an anode recombine at a light emitting center in an EL layer including a light emitting body interposed between a pair of electrodes, a molecular exciton is formed, and light is emitted when the molecular exciton returns to a ground state while releasing energy. It is known that there are a singlet excited state and a triplet excited state in an excited state, and it is considered that light emission can be achieved through either of the excited states.

[0005] In such a light emitting element, an organic compound is mainly used as the EL layer. Since it has a large influence on improvement in element characteristics of a light emitting element, various novel organic compounds have been developed (for example, see Patent Document 1).

[0006] [Patent Document 1] Japanese Published Patent Application No. 2007-189001 SUMMARY

[0007] The compound having a dibenzo[f,h]quinoxaline ring reported in the above patent document 1 has a planar structure, and thus has a problem of easy crystallization. A light-emitting element using a compound that easily crystallizes has a short lifetime. Further, if another skeleton is directly bonded to the dibenzo[f,h]quinoxaline ring so that the compound has a sterically bulky structure, it is sometimes possible to extend the conjugated system to cause a decrease in the triplet excitation energy. When the triplet excitation energy decreases, the emission efficiency also decreases, and thus the element characteristics of a light-emitting element using such a compound also decrease.

[0008] Thus, one embodiment of the present application provides a novel heterocyclic compound. In particular, a novel heterocyclic compound which can improve the element characteristics of a light-emitting element is provided. In addition, one embodiment of the present application provides a novel heterocyclic compound which has high emission efficiency and heat resistance. In addition, one embodiment of the present application provides a novel heterocyclic compound which can be used for a light-emitting element. In addition, one embodiment of the present application provides a novel heterocyclic compound which can be used for an EL layer of a light-emitting element. In particular, a light-emitting element with high heat resistance, a light-emitting element with high emission efficiency and low power consumption, and a light-emitting element with a long lifetime are provided. In addition, one embodiment of the present application provides a novel light-emitting element. In addition, a novel light-emitting device, a novel electronic device, or a novel illumination device is provided. Note that the description of these objects does not preclude the existence of other objects. One embodiment of the present application does not necessarily achieve all the above-described objects. In addition, objects other than the above can be extracted from the description, drawings, claims, and the like.

[0009] One embodiment of the present application is a heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxaline group is bonded to a substituted or unsubstituted benzo bisbenzofuran group through a substituted or unsubstituted arylene group.

[0010] One embodiment of the present application is a heterocyclic compound represented by General Formula (G1).

[0011] [Chemical Formula 1]

[0012]

[0013] In General Formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxaline group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzo bisbenzofuran group. When the arylene groups represented by Ar 1 and Ar 2 have a substituent, the substituents can be bonded to each other to form a ring.

[0014] In another embodiment of the present application, in the above general formula (Gl), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzodibenzofuranyl group. In the benzodibenzofuranyl group, any one of the carbon atoms adjacent to the carbon atom bonded to oxygen of the furan ring in the carbon atoms not forming the furan ring is bonded to Ar 2 . When the arylene group represented by Ar 1 and Ar 2 has a substituent, the substituents can be bonded to each other to form a ring.

[0015] Another embodiment of the present application is a heterocyclic compound represented by the following general formula (G2).

[0016] [Chemical Formula 2]

[0017]

[0018] In the general formula (G2), A represents a substituted or unsubstituted benzodibenzofuranyl group, R 1 to R 9 independently represent hydrogen, an alkyl group having 1 to 4 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms. When the arylene group represented by Ar 1 and Ar 2 has a substituent, the substituents can be bonded to each other to form a ring.

[0019] In the above structure, Ar 2 in the general formula (Gl) or the general formula (G2) represents a substituted or unsubstituted phenylene group or a substituted or unsubstituted biphenyl-4,4’-diyl group, and n represents 0.

[0020] In the above structure, Ar 2 in the general formula (Gl) or the general formula (G2) represents a substituted or unsubstituted m-phenylene group or a substituted or unsubstituted biphenyl-3,3’-diyl group, and n represents 0.

[0021] In each of the above structures, A in General Formula (G1) or General Formula (G2) is any one of General Formula (A1) to General Formula (A3) below, in which any one of the carbon atoms adjacent to the carbon atom bonded to oxygen of the furan ring among the carbon atoms not forming the furan ring is bonded to Ar 2 .

[0022] [Chemical Formula 3]

[0023]

[0024] In General Formula (A1) to General Formula (A3), the benzene ring can also have a substituent, which is a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.

[0025] Another embodiment of the present application is a heterocyclic compound represented by Structural Formula (101), Structural Formula (107), Structural Formula (149), or Structural Formula (150) below.

[0026] [Chemical Formula 4]

[0027]

[0028] The heterocyclic compound of one embodiment of the present application is a material with a high T1 level, and thus can be used as a host material which can be combined with a light-emitting substance (dopant) such as a phosphorescent material.

[0029] In addition, the heterocyclic compound of one embodiment of the present application is a material with high electron-transport properties. Thus, the heterocyclic compound can be used not only in a light-emitting layer in an EL layer of a light-emitting element but also in an electron-transport layer or the like. Furthermore, the heterocyclic compound of one embodiment of the present application is a light-emitting substance. Thus, in a light-emitting layer, the heterocyclic compound can be used not only as a host material used in combination with a light-emitting substance such as a phosphorescent material but also as a light-emitting substance. Thus, a light-emitting element using the heterocyclic compound of one embodiment of the present application is included in the category of one embodiment of the present application.

[0030] That is, another embodiment of the present application is a light-emitting element using a heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzo bisbenzofuranyl group are bonded to each other through a substituted or unsubstituted arylene group.

[0031] Another embodiment of the present application is a light-emitting element using a heterocyclic compound in which a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group and a substituted or unsubstituted benzo[2,1-b:3,2'-b']dithiophenyl group are bonded to each other via a substituted or unsubstituted arylene group, and in the benzo[2,1-b:3,2'-b']dithiophenyl group, any one of carbon atoms adjacent to a carbon atom to which an oxygen atom of a furan ring is bonded is bonded to the arylene group.

[0032] In addition, in each of the above structures, the light-emitting element includes a light-emitting layer, and the light-emitting layer includes the heterocyclic compound and a light-emitting substance.

[0033] Further, one embodiment of the present application includes not only a light-emitting device including a light-emitting element but also a lighting device including a light-emitting device. Thus, the light-emitting device in this specification refers to an image display device or a light source (including a lighting device). In addition, the light-emitting device sometimes includes a module in which a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) is attached to a light-emitting device, a module in which a printed wiring board is provided on the tip of a TCP, or a module in which an IC (Integrated Circuit) is directly mounted on a light-emitting element by a COG (Chip On Glass) method.

[0034] According to one embodiment of the present application, a novel heterocyclic compound can be provided. In particular, according to one embodiment of the present application, a novel heterocyclic compound which can improve characteristics of a light-emitting element can be provided. In addition, according to one embodiment of the present application, a novel heterocyclic compound which has high light-emitting efficiency and heat resistance can be provided. Further, according to one embodiment of the present application, a novel heterocyclic compound which can be used for a light-emitting element can be provided. In addition, according to one embodiment of the present application, a novel heterocyclic compound which can be used for an EL layer of a light-emitting element can be provided. In particular, according to one embodiment of the present application, a light-emitting element which has high heat resistance, a light-emitting element which has high light-emitting efficiency and low power consumption, and a light-emitting element which has a long lifetime can be provided. According to one embodiment of the present application, a novel light-emitting element can be provided. According to one embodiment of the present application, a novel light-emitting device, a novel electronic device, or a novel lighting device can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0035] FIG. 1A and FIG. 1B are cross-sectional views each illustrating a structure of a light-emitting element;

[0036] FIG. 2A and FIG. 2B are cross-sectional views each illustrating a structure of a light-emitting element;

[0037] FIGS. 3A-3C is a diagram illustrating a light-emitting device;

[0038] FIG. 4A and FIG. 4B is a diagram illustrating a light-emitting device;

[0039] FIG. 5A1 , FIG. 5A2 , FIG. 5B , FIG. 5C , FIG. 5D1 , FIG. 5D2 and FIG. 5D3 is a diagram illustrating an electronic device;

[0040] FIGS. 6A-6C is a diagram illustrating an electronic device;

[0041] FIG. 7A and FIG. 7B is a diagram illustrating a car;

[0042] FIGS. 8A-8D is a diagram illustrating a lighting device;

[0043] FIG. 9 is a diagram illustrating a lighting device;

[0044] FIG. 10A and FIG. 10B is a diagram illustrating one example of a touch screen;

[0045] FIG. 11A and FIG. 11B is a diagram illustrating one example of a touch screen;

[0046] FIG. 12A and FIG. 12B is a diagram illustrating one example of a touch screen;

[0047] FIG. 13A and FIG. 13B are a block diagram and a timing chart of a touch sensor, respectively;

[0048] FIG. 14 is a circuit diagram of a touch sensor;

[0049] FIG. 15A and FIG. 15B are H-NMR spectra of the heterocyclic compounds represented by Structural Formula (101); 1

[0050] FIG. 16A and FIG. 16B are ultraviolet-visible absorption spectra and emission spectra of the heterocyclic compounds represented by Structural Formula (101);

[0051] FIG. 17A and FIG. 17B are H-NMR spectra of the heterocyclic compounds represented by Structural Formula (107);​1 H-NMR spectrum;

[0052] FIG. 18A and FIG. 18B are UV-visible absorption spectrum and emission spectrum of the heterocyclic compound represented by Structural Formula (107);

[0053] FIG. 19A and FIG. 19B are UV-visible absorption spectrum and emission spectrum of the heterocyclic compound represented by Structural Formula (149); 1 H-NMR spectrum;

[0054] FIG. 20A and FIG. 20B are UV-visible absorption spectrum and emission spectrum of the heterocyclic compound represented by Structural Formula (149);

[0055] FIG. 21A and FIG. 21B are UV-visible absorption spectrum and emission spectrum of the heterocyclic compound represented by Structural Formula (150); 1 H-NMR spectrum;

[0056] FIG. 22A and FIG. 22B are UV-visible absorption spectrum and emission spectrum of the heterocyclic compound represented by Structural Formula (150);

[0057] FIG. 23 is a graph showing the light-emitting element;

[0058] FIG. 24 is a graph showing current density-luminance characteristics of the light-emitting elements 1 to 4;

[0059] FIG. 25 is a graph showing voltage-luminance characteristics of the light-emitting elements 1 to 4;

[0060] FIG. 26 is a graph showing luminance-current efficiency characteristics of the light-emitting elements 1 to 4;

[0061] FIG. 27 is a graph showing voltage-current characteristics of the light-emitting elements 1 to 4;

[0062] FIG. 28 is a graph showing emission spectrum of the light-emitting elements 1 to 4;

[0063] FIG. 29 is a graph showing reliability of the light-emitting elements 1 to 4;

[0064] FIG. 30 is a graph showing time change in external quantum efficiency characteristics of the light-emitting elements 1 to 3 and the comparative light-emitting element 5;

[0065] FIG. 31 is a mass spectrum of 2mBbfPDBq;

[0066] FIG. 32 is a mass spectrum of 2mBbfPDBq. DETAILED DESCRIPTION

[0067] Hereinafter, an embodiment of the present application will be explained in detail with reference to the drawings. Note that the present application is not limited to the following explanation, and modes and details thereof can be modified in various ways without departing from the spirit and scope of the present application. Therefore, the present application should not be interpreted as being limited only to the contents described in the following embodiment.

[0068] In addition, "film" and "layer" can be interchanged depending on the situation or state. For example, "conductive layer" can be interchanged as "conductive film" in some cases. Further, "insulating film" can be interchanged as "insulating layer" in some cases.

[0069] Embodiment 1

[0070] In this embodiment, a heterocyclic compound of one embodiment of the present application is described.

[0071] The heterocyclic compound shown in this embodiment has the following feature: a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group is bonded to a substituted or unsubstituted benzo bisbenzofuranyl group through a substituted or unsubstituted arylene group.

[0072] It is generally known that as the number of condensed rings of a molecular structure of an organic compound is increased, heat resistance of the organic compound having a structure with a larger number of condensed rings is improved as the molecular weight increases, and long service life can be expected when the organic compound is used for a light-emitting element. However, since the organic compound has a molecular structure with higher planarity as the number of condensed rings is increased, there are problems such as reduction in heat resistance due to easy crystallization of a thin film of the organic compound, reduction in the triplet excitation energy (T1 level) of the compound, and difficulty in synthesis and purification of the compound due to reduction in solubility of the compound. In contrast, in the heterocyclic compound of one embodiment of the present application, a condensed ring including a hetero atom is used to expand the skeleton of an organic molecule, and thus a compound with a high T1 level can be provided. By bonding a dibenzo[f,h]quinoxalinyl group with high planarity to a benzo bisbenzofuranyl group through an arylene group, a bulky compound is realized, and thus crystallization can be inhibited to improve heat resistance. Thus, the heterocyclic compound described in this embodiment is a heterocyclic compound having a structure represented by General Formula (G1).

[0073] [Chemical Formula 5]

[0074]

[0075] In General Formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzo bisbenzofuranyl group. When Ar 1 and Ar 2 have a substituent, the substituents can also be bonded to each other to form a ring.

[0076] In addition, as another structure, in the heterocyclic compound represented by General Formula (G1) above, DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, and A represents a substituted or unsubstituted benzo bisbenzofuranyl group. When Ar 2 in the benzo bisbenzofuranyl group is bonded to any one of the carbon atoms adjacent to the carbon atom of the furan ring to which oxygen is bonded. 1 and Ar 2 have a substituent, the substituents can also be bonded to each other to form a ring.

[0077] As the arylene group having 6 to 13 carbon atoms represented by Ar 1 or Ar 2 in General Formula (G1), a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthalene-diyl group, a substituted or unsubstituted biphenyl-diyl group, a substituted or unsubstituted fluorene-diyl group, and the like can be given, and specifically, arylene groups represented by Structural Formula (α1) to (α15) below, and the like can be given.

[0078] [Chemical Formula 6]

[0079]

[0080] In General Formula (G1), the unsubstituted benzo bisbenzofuranyl group in the substituted or unsubstituted benzo bisbenzofuranyl group represented by A is any one of General Formula (A1) to General Formula (A7) below.

[0081] [Chemical Formula 7]

[0082]

[0083] When the benzodibenzofuranyl group represented by A in General Formula (G1) has a substituent, the benzene ring in General Formula (A1) to General Formula (A7) can also have a substituent, and as the substituent, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 7 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms can be given.

[0084] When the alkyl group having 1 to 6 carbon atoms is a substituent in General Formula (A1) to General Formula (A7), as a specific example of the alkyl group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, a neohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, a 2,3-dimethylbutyl group, and the like can be given.

[0085] Further, when the cycloalkyl group having 5 to 7 carbon atoms is a substituent in General Formula (A1) to General Formula (A7), as a specific example of the cycloalkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and the like can be given.

[0086] Further, when the aryl group having 6 to 13 carbon atoms is a substituent in General Formula (A1) to General Formula (A7), as a specific example of the aryl group, a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, an indenyl group, and the like can be given.

[0087] Substitution in General Formula (G1) means substitution with an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group, or an aryl group having 6 to 12 carbon atoms such as a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenyl group, a 3-biphenyl group, a 4-biphenyl group, and the like. These substituents can also be bonded to each other to form a ring. For example, when the fluorene-diyl group of the arylene group is a 9,9-diphenyl-9H-fluorene-2,7-diyl group having two phenyl groups as substituents at the 9-position, the phenyl groups can also be bonded to each other to become spiro-9,9'-bianthracene-2,7-diyl.

[0088] Further, another structure of the heterocyclic compound of one embodiment of the present application is a heterocyclic compound having a structure represented by General Formula (G2).

[0089] [Chemical Formula 8]

[0090]

[0091] In General Formula (G2), A represents a substituted or unsubstituted benzodibenzofuranyl group, R 1 to R 9respectively independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, and Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms. When the arylene group represented by Ar 1 and Ar 2 When the arylene group represented by Ar

[0092] As a specific example of the arylene group having 6 to 13 carbon atoms represented by Ar 1 or Ar 2 in General Formula (G2), an arylene group represented by the following structural formula (al) to (al5) and the like can be given.

[0093] [Chemical Formula 9]

[0094]

[0095] In General Formula (G2), the unsubstituted benzobisbenzofuran group among the substituted or unsubstituted benzobisbenzofuran groups represented by A is any one of the following General Formula (Al) to General Formula (A7).

[0096] [Chemical Formula 10]

[0097]

[0098] When the benzobisbenzofuran group represented by A in General Formula (G2) has a substituent, the benzene ring in General Formula (Al) to General Formula (A7) can also have a substituent, and as the substituent, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms or an aryl group having 6 to 13 carbon atoms, which is substituted or unsubstituted, can be given.

[0099] When General Formula (Al) to General Formula (A7) have an alkyl group having 1 to 6 carbon atoms as the substituent, as a specific example of the alkyl group, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, a neohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, a 2,3-dimethylbutyl group and the like can be given.

[0100] Further, when General Formula (Al) to General Formula (A7) have a cycloalkyl group having 5 to 7 carbon atoms as the substituent, as a specific example of the alkyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and the like can be given.

[0101] In addition, when the general formula (A1) to general formula (A7) is a substituent having an aryl group having 6 to 13 carbon atoms, specific examples of such aryl group include phenyl, biphenyl, naphthyl, fluorenyl, indene, etc.

[0102] R in the above general formula (G2) 1 To R 9 Specific examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, pentyl, isopentyl, sec-pentyl, tert-pentyl, neopentyl, hexyl, isohexyl, sec-hexyl, tert-hexyl, neohexyl, 3-methylpentyl, 2-methylpentyl, 2-ethylbutyl, 1,2-dimethylbutyl, and 2,3-dimethylbutyl.

[0103] R in the above general formula (G2) 1 To R 9 Specific examples of aryl groups with 6 to 13 carbon atoms include phenyl, biphenyl, tolyl, naphthyl, xylyl, fluorenyl, and indene.

[0104] In general formula (G2), substitution refers to alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, sec-butyl, tert-butyl, n-pentyl, and n-hexyl, or aryl groups having 6 to 12 carbon atoms, such as phenyl, o-tolyl, m-tolyl, p-tolyl, 1-naphthyl, 2-naphthyl, 2-biphenyl, 3-biphenyl, and 4-biphenyl. These substituents can also bond with each other to form a ring. For example, when the fluorene-diyl arylene is 9,9-diphenyl-9H-fluorene-2,7-diyl with two phenyl groups at the 9-position as substituents, these phenyl groups can also bond with each other to form spiro-9,9'-bifluorene-2,7-diyl.

[0105] Next, the specific structural formula of a heterocyclic compound according to one aspect of the present invention is shown below. Note that the present invention is not limited to the following structural formula.

[0106] [Chemical Formula 11]

[0107]

[0108] [Chemical Formula 12]

[0109]

[0110] [Chemical Formula 13]

[0111]

[0112] [Chemical Formula 14]

[0113]

[0114] [Chemical Formula 15]

[0115]

[0116] [Chemical Formula 16]

[0117]

[0118] [Chemical Formula 17]

[0119]

[0120] [Chemical Formula 18]

[0121]

[0122] [Chemical Formula 19]

[0123]

[0124] [Chemical Formula 20]

[0125]

[0126] [Chemical Formula 21]

[0127]

[0128] [Chemical Formula 22]

[0129]

[0130] [Chemical Formula 23]

[0131]

[0132] [Chemical Formula 24]

[0133]

[0134] [Chemical Formula 25]

[0135]

[0136] [Chemical Formula 26]

[0137]

[0138] [Chemical Formula 27]

[0139]

[0140] [Chemical Formula 28]

[0141]

[0142] [Chemical Formula 29]

[0143]

[0144] [Chemical Formula 30]

[0145]

[0146] [Chemical Formula 31]

[0147]

[0148] [Chemical Formula 32]

[0149]

[0150] [Chemical Formula 33]

[0151]

[0152] [Chemical Formula 34]

[0153]

[0154] [Chemical Formula 35]

[0155]

[0156] [Chemical Formula 36]

[0157]

[0158] [Chemical Formula 37]

[0159]

[0160] [Chemical Formula 38]

[0161]

[0162] The heterocyclic compounds represented by Structural Formula (101) to Structural Formula (184), Structural Formula (201) to Structural Formula (400) are merely examples of the heterocyclic compounds represented by General Formula (G1), General Formula (G2), and the heterocyclic compounds of one embodiment of the present application are not limited thereto.

[0163] Next, one example of a synthesis method of the heterocyclic compound represented by General Formula (G1) of one embodiment of the present application will be described. As the synthesis method of the organic compound represented by General Formula (G1), various reactions can be used, and for example, the organic compound represented by General Formula (G1) can be synthesized by the following method. Note that the synthesis method of the organic compound represented by General Formula (G1) of one embodiment of the present application is not limited to the following synthesis method.

[0164] [Chemical Formula 39]

[0165]

[0166] In General Formula (G1), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzo bisbenzofuranyl group. When the arylene group represented by Ar 1 and Ar 2 has a substituent, the substituents can be bonded to each other to form a ring. Of the carbon atoms in the benzo bisbenzofuranyl group which do not form the furan ring, either of the carbon atoms adjacent to the carbon atom bonded to oxygen of the furan ring is bonded to Ar 2 .

[0167] Synthesis Scheme A of the heterocyclic compound represented by General Formula (G1) is shown below. As shown in Synthesis Scheme A, the heterocyclic compound represented by General Formula (G1) can be synthesized by coupling a dibenzo[f,h]quinoxaline compound (Compound 1) and a benzo bisbenzofuranyl compound (Compound 2).

[0168] [Chemical Formula 40]

[0169]

[0170] In Synthesis Scheme (A), DBq represents a substituted or unsubstituted dibenzo[f,h]quinoxalinyl group, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzo bisbenzofuranyl group. When the arylene group represented by Ar 1 and Ar 2 has a substituent, the substituents can be bonded to each other to form a ring.

[0171] In Synthesis Scheme (A), in the case where a Suzuki-Miyaura coupling reaction using a palladium catalyst is performed, X 1and X 2 represents a halogen group, a boronic acid group, an organoboron group, or a trifluoromethylsulfonyl group, and the halogen group is preferably iodine, bromine, or chlorine. In the above reaction, a palladium compound such as bis(dibenzylideneacetone)palladium(0), palladium(II) acetate, [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II), tetrakis(triphenylphosphine)palladium(0), and a ligand such as tri(tert-butyl)phosphine, tri(n-hexyl)phosphine, tricyclohexylphosphine, di(l-adamantyl)-n-butylphosphine, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, and tri(o-tolyl)phosphine can be used.

[0172] In the reaction shown in Synthesis Scheme (A), an organic base such as sodium tert-butoxide, an inorganic base such as potassium carbonate, cesium carbonate, sodium carbonate, and the like can be used. Also, as the solvent, toluene, xylene, benzene, tetrahydrofuran, dioxane, ethanol, methanol, water, and the like can be used. Note that the reagent classes that can be used in the above reaction are not limited to the above reagent classes.

[0173] The reaction in Synthesis Scheme (A) is not limited to the Suzuki-Miyaura coupling reaction, and the Migita-Kosugi-Stille coupling reaction using an organotin compound, the Kumada-Tsuneda-Corriu coupling reaction using a Grignard reagent, the Negishi coupling reaction using an organozinc compound, a reaction using copper or a copper compound, and the like can be used.

[0174] When the Migita-Kosugi-Stille coupling reaction is used in Synthesis Scheme (A), one of X 1 and X 2 represents an organotin group, and the other represents a halogen group. That is, one of Compound 1 and Compound 2 represents an organotin compound.

[0175] When the Kumada-Tsuneda-Corriu coupling reaction is used in Synthesis Scheme (A), one of X 1 and X 2 represents a magnesium halide group, and the other represents a halogen group. That is, one of Compound 1 and Compound 2 represents a Grignard reagent.

[0176] When the Negishi coupling reaction is used in Synthesis Scheme (A), one of X 1 and X 2 represents an organozinc group, and the other represents a halogen group. That is, one of Compound 1 and Compound 2 represents an organozinc compound.

[0177] Note that in the synthesis of the organic compound (G1) of the present application, the synthesis method is not limited to Synthesis Method (A).

[0178] As described above, although an example of a method for synthesizing the heterocyclic compound of one embodiment of the present application is described, one embodiment of the present application is not limited to this, and a compound synthesized by another method can be used.

[0179] Since the heterocyclic compound of one embodiment of the present application has electron-transport property and hole-transport property, it can be used as a host material of a light-emitting layer or for an electron-transport layer, a hole-transport layer. Further, since the heterocyclic compound of one embodiment of the present application is a material with a high T1 level, it is preferably used as a host material in combination with a substance that emits phosphorescence (a phosphorescent material). Further, since the heterocyclic compound of one embodiment of the present application exhibits fluorescent emission, it can be used as a light-emitting substance of a light-emitting element itself. Thus, a light-emitting element including the heterocyclic compound is also included in the category of one embodiment of the present application.

[0180] In addition, by using the heterocyclic compound of one embodiment of the present application, a light-emitting element, a light-emitting device, an electronic device, or a lighting device with high emission efficiency can be achieved. Furthermore, one embodiment of the present application can achieve a light-emitting element, a light-emitting device, an electronic device, or a lighting device with low power consumption.

[0181] In this embodiment mode, one embodiment of the present application is described. Further, in another embodiment mode, one embodiment of the present application will be described. However, one embodiment of the present application is not limited to this. That is, in this embodiment mode and another embodiment mode, various modes of the present application are described, and thus one embodiment of the present application is not limited to a specific mode. Although an example in which one embodiment of the present application is applied to a light-emitting element is described, one embodiment of the present application is not limited to this. Depending on circumstances, one embodiment of the present application can be applied to an object other than a light-emitting element. Depending on circumstances, one embodiment of the present application can not be applied to a light-emitting element.

[0182] The structure described in this embodiment mode can be implemented in combination with the structure described in another embodiment mode as appropriate.

[0183] Embodiment 2

[0184] In this embodiment mode, a light-emitting element of one embodiment of the present application is described with reference to FIG. 1A and FIG. 1B

[0185] In the light-emitting element described in this embodiment mode, an EL layer 102 including a light-emitting layer 113 is interposed between a pair of electrodes (a first electrode (anode) 101 and a second electrode (cathode) 103), and the EL layer 102 includes a hole-injection layer 111, a hole-transport layer 112, an electron-transport layer 114, an electron-injection layer 115, and the like in addition to the light-emitting layer 113.

[0186] ​When a voltage is applied to the light-emitting element described above, holes injected from the first electrode 101 side recombine with electrons injected from the second electrode 103 side in the light-emitting layer 113, and energy generated thereby causes an organic metal complex or the like contained in the light-emitting layer 113 to emit light.

[0187] In addition, the hole-injection layer 111 in the EL layer 102 is a layer that can inject holes into the hole-transport layer 112 or the light-emitting layer 113, and can be formed using, for example, a substance having a high hole-transport property and an acceptor substance. At this time, the acceptor substance extracts electrons from the substance having a high hole-transport property, and thus holes are generated. Thus, holes are injected from the hole-injection layer 111 to the light-emitting layer 113 through the hole-transport layer 112. Alternatively, a substance having a high hole-injection property can be used as the hole-injection layer 111. For example, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, or manganese oxide can be used. Alternatively, a phthalocyanine-based compound such as phthalocyanine (abbreviation: H2Pc), copper phthalocyanine (CuPc), or the like; an aromatic amine compound such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(l,l'-biphenyl)-4,4'-diamine (abbreviation: DNTPD), or the like; or a high molecular compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (abbreviation: PEDOT / PSS) can be used to form the hole-injection layer 111.

[0188] Next, a specific example of the production of the light-emitting element described in this embodiment will be described.

[0189] As the first electrode (anode) 101 and the second electrode (cathode) 103, a metal, an alloy, a conductive compound, a mixture thereof, or the like can be used. Specifically, in addition to indium tin oxide, indium tin oxide containing silicon or silicon oxide, indium zinc oxide, 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), titanium (Ti), an alkali metal belonging to Group 1 or Group 2 in the periodic table, such as lithium (Li) and cesium (Cs), an alkaline earth metal such as calcium (Ca) and strontium (Sr), magnesium (Mg), an alloy containing these metals (MgAg, AlLi), a rare earth metal such as europium (Eu) and ytterbium (Yb), an alloy containing these metals, graphene or a graphene compound such as graphene oxide, and the like can be used. The first electrode (anode) 101 and the second electrode (cathode) 103 can be formed by a sputtering method, an evaporation method (including a vacuum evaporation method), or the like, for example.

[0190] As a substance having a high hole-transport property for the hole-injection layer 111 and the hole-transport layer 112, various organic compounds such as an aromatic amine compound, a carbazole derivative, an aromatic hydrocarbon, a high molecular compound (an oligomer, a dendrimer, a polymer, or the like), and the like can be used. Specifically, a substance having a hole mobility of 1 x 10 -6 cm 2 or more is preferably used. Further, the layer formed using a substance having a high hole-transport property can be a single layer or a stacked layer of two or more layers. Hereinafter, specific examples of an organic compound that can be used as a hole-transport substance are given.

[0191] For example, as an aromatic amine compound, N,N'-bis(p-tolyl)-N,N'-diphenyl-p- phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N- phenylamino]biphenyl (abbreviation: DPAB), DNTPD, 1,3,5-tris[N-(4- diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 4,4'-bis[N-(1- naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or a-NPD), N,N'-bis(3- methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4',4"- tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA), 4,4',4"-tris(N,N- diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4"-tris[N-(3- methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(spiro- 9,9'-bifluorene-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), and the like can be given.

[0192] As a carbazole derivative, 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9- phenylcarbazole (abbreviation: 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), and the like can be given. In addition to the above, 4,4'-di(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 (abbreviation: CzPA), 1,4-bis[4-(N-carbazolyl)phenyl]- 2,3,5,6-tetraphenylbenzene, and the like can be given.

[0193] In addition, as the aromatic hydrocarbon, for example, 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-l-naphthyl)anthracene (abbreviation: DMNA), 2-tert-butyl-9,10-bis[2-(l-naphthyl)phenyl]anthracene, 9,10-bis[2-(l-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(l-naphthyl)anthracene, 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, and the like can be given. In addition to these, pentacene, coronene, and the like can be used. Like this, an aromatic hydrocarbon having a hole mobility of 1 x 10 -6 cm 2 or more and having 14 to 42 carbon atoms is preferably used. The aromatic hydrocarbon can have a vinyl skeleton. As the aromatic hydrocarbon having a vinyl group, for example, 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), and the like can be given.

[0194] In addition, a high molecular compound such as poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD), and the like can be used.

[0195] As the acceptor material for the hole injection layer 111 and the hole transport layer 112, a compound having an electron-withdrawing group (halogen or cyano) such as 7,7,8,8-tetracyano-2,3,5,6-tetrachloroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), and the like can be given. In particular, a compound in which an electron-withdrawing group such as HAT-CN is bonded to a condensed aromatic ring having a plurality of hetero atoms is thermally stable, and is thus preferable. Further, an oxide of a metal belonging to Group 4 to Group 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 preferable because they have high electron accepting properties. Among them, molybdenum oxide is particularly preferable because it is stable in the air, has low hygroscopic property, and is easy to handle.

[0196] The light-emitting layer 113 is a layer containing a light-emitting substance. As the light-emitting substance, a fluorescent light-emitting substance and a phosphorescent light-emitting substance can be given. As the phosphorescent light-emitting substance, specifically, an organometallic complex is used. When an organometallic complex (guest material) is used in the light-emitting layer 113, a substance having a larger triplet excited energy than the organometallic complex is preferably contained as a host material. In addition, the light-emitting layer 113 can contain two kinds of organic compounds (any of the above host materials can be used) which form an exciplex when carriers (electrons and holes) recombine in the light-emitting layer 113, in addition to the light-emitting substance. It is particularly preferable to combine a compound that easily accepts an electron (a material having electron-transporting properties) and a compound that easily accepts a hole (a material having hole-transporting properties) in order to efficiently form an exciplex. When a material having electron-transporting properties and a material having hole-transporting properties are combined to obtain a host material that forms an exciplex, the balance between carriers in the light-emitting layer can be easily optimized by adjusting the mixing ratio of the material having electron-transporting properties and the material having hole-transporting properties. By optimizing the balance between carriers in the light-emitting layer, the region where electrons and holes recombine in the light-emitting layer can be made to be less biased. By making the region where recombination occurs less biased, the reliability of the light-emitting element can be improved.

[0197] As the compound (material having electron-transporting property) which is preferably used at the time of forming the above-mentioned exciplex, a π-electron deficient heteroaromatic compound such as a nitrogen-containing heteroaromatic compound or a metal complex or the like can be used. Specifically, metal complexes such as bis(10-hydroxybenzo[h]quinoline)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-hydroxyquinoline)(4-phenylphenol)aluminum(III) (abbreviation: BAIq), bis(8-hydroxyquinoline)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenol]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenol]zinc(II) (abbreviation: ZnBTZ), and the like; heterocyclic compounds having a polyazole skeleton such as 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: COll), 2,2',2"-(1,3,5-benzinetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzo[f,h]thien-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), and the like; heterocyclic compounds having a diazine skeleton such as 2-[3-(dibenzo[f,h]thien-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzo[f,h]thien-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4-(3,6-di-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzo[f,h]thien-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), 6-[3-(dibenzo[f,h]thien-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzo[b,d]thienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), and the like can be used.2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn) and the like having a triazine skeleton, and 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tris[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB) and the like having a pyridine skeleton. Among these, the heterocyclic compounds having a diazine skeleton and a triazine skeleton and the heterocyclic compounds having a pyridine skeleton have high reliability, and thus are preferable. In particular, the heterocyclic compounds having a diazine (pyrimidine or pyrazine) skeleton and a triazine skeleton have high electron-transport properties, and are also effective in reducing the driving voltage.

[0198] As the compound (material having a hole-transport property) which is preferably used at the time of forming the above-described exciplex, a π-electron rich heteroaromatic compound (for example, a carbazole derivative or an indole derivative) or an aromatic amine, or the like can be appropriately used. Specifically, 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), 4,4',4"-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1'-TNATA), 2,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-difluorene (abbreviation: DPA2SF), N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPFN), N,N',N"-triphenyl-N,N',N"-tris(9-phenylcarbazol-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-difluorene (abbreviation: DPASF), N,N'-bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), NPB, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), BSPB, 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 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 (abbreviation: DFLADFL), PCzPCA1, 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), DNTPD, 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), PCzPCA2, 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4',4"-diphenyl-1,1':3',1''-terphenyl-3''-amine (abbreviation: DPA3), 3,5-diphenyl-4- (9-phenylcarbazol-3-yl)phenyl (abbreviation: DCZ), 3,5-diphenyl-4-(15-phenyl-20-1H-indol-3-yl)phenyl (abbreviation: DPi), 4-(diphenylamino)-4'-(9-phenylcarbazol-3-yl)-triphenylamine (abbreviation: YGAPA), 4-(9-phenylcarbazol-3-yl)-4'-(9-phenyl-9H-carbazol-3-yl)-triphenylamine (abbreviation: PCAPA), 4,4'-diphenyl-4"-decyanophenyl (abbreviation: DCB), and the like can be given.4'-diphenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]fluorine-9-phenylcarbazole (abbreviation: PCzPCN1), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluorene-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluorene-2-amine (abbreviation: PCBASF), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), and the like having an aromatic amine skeleton; 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-bis(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 9-phenyl-9H-3-(9-phenyl-9H-carbazol-3-yl)carbazole (abbreviation: PCCP), and the like having a carbazole skeleton; 4,4',4"-(benzene-1,3,5-triyl)tris(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), and the like having a thiophene skeleton; and 4,4',4"-(benzene-1,3,5-triyl)tris(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), and the like having a furan skeleton. Among these, the compounds having an aromatic amine skeleton and the compounds having a carbazole skeleton have high reliability and high hole-transport properties, and are also effective in reducing the driving voltage, and are thus preferable.

[0199] In addition, by forming the light-emitting layer 113 by including the above-described organometallic complex (guest material) and the host material, phosphorescent emission with high emission efficiency can be obtained from the light-emitting layer 113.

[0200] The light-emitting layer 113 is not limited toFIG. 1A The single-layer structure shown can also have, for example, the following characteristics. FIG. 1B A stacked structure of two or more layers as shown. Note that in this case, a structure in which light emission is obtained from each of the stacked layers is adopted. For example, a structure in which fluorescence emission is obtained from the first light-emitting layer 113(a1) and phosphorescence emission is obtained from the second light-emitting layer 113(a2) stacked on the first layer can be adopted. Note that the stacking order can also be reversed. Furthermore, it is preferable that the layer in which phosphorescence emission is obtained has a structure in which light emission is obtained by energy transfer from the excimer complex to the dopant. Furthermore, regarding the emission color, the emission color that can be obtained from one layer can be the same as or different from the emission color that can be obtained from another layer. In the case that they are different, for example, a structure in which blue emission is obtained from one layer and orange or yellow emission is obtained from another layer can be adopted. Furthermore, each layer can also have a structure containing multiple dopants.

[0201] When the light-emitting layer 113 has a stacked structure, light-emitting materials capable of converting singlet excitation energy into light emission or capable of converting triplet excitation energy into light emission can be used alone or in combination. Examples of such materials include the following.

[0202] As a luminescent substance capable of converting singlet excitation energy into light emission, examples include substances that emit fluorescence (fluorescent compounds).

[0203] As the substance that emits fluorescence, N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N"-(2-tert-butylanthracen-9,10-diylbis-4,1-phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N",N",N",N"'-octaphenyl-2,3-naphthalimide (abbreviation: DNPA), 4,4',4"-tris(5-tert-butyl-2-phenyl)phenylamino)triphenylamine (abbreviation: DPA-T2PA), 4,4',4"-tris(5-tert-butyl-2-phenyl)phenylamino)phenylamine (abbreviation: DPA-T), and the like can be given. (chrysene)-2,7,10,15-tetramine (abbreviation: DBC1), Coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA), Coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), Rubrene, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenylbenzo[2,1-c(1)]phenanthrene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]vinyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizol-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl) naphthacene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl) acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizol-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizol-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]vinyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizol-9-yl)vinyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), and the like.

[0204] As the light-emitting substance that converts triplet excitation energy into light emission, for example, a substance that emits phosphorescence (phosphorescent compound), a TADF material (thermally activated delayed fluorescence) that exhibits thermally activated delayed fluorescence (TADF) can be given. The delayed fluorescence exhibited by the TADF material refers to light emission whose spectrum is the same as that of general fluorescence but whose service life is extremely long. The service life is 1 x 10 -6 seconds or more, and preferably 1 x 10 -3 seconds or more.

[0205] As the substance that emits phosphorescence, bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridine-N,C 2'}iridium(III) picolinate (abbreviation: [Ir(CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyridine-N,C 2' ]iridium(III) acetylacetonate (abbreviation: FIracac), tris(2-phenylpyridine)iridium(III) (abbreviation: [Ir(ppy)3]), bis(2-phenylpyridine)iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac)3(Phen)]), bis(benzo[h]quinoline)iridium(III) acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), bis(2,4-diphenyl-1,3-oxazole-N,C 2' )iridium(III) acetylacetonate (abbreviation: [Ir(dpo)2(acac)]), bis{2-[4'-(perfluorophenyl)phenyl]pyridine-N,C 2'}iridium(III) acetylacetonate (abbreviation: [Ir(p-PF-ph)2(acac)]), bis(2-phenylbenzothiazole-N,C 2' )iridium(III) acetylacetonate (abbreviation: [Ir(bt)2(acac)]), bis[2-(2'-benzo[4,5-α]thienyl)pyridine-N,C 3' ]iridium(III) acetylacetonate (abbreviation: [Ir(btp)2(acac)]), bis(1-phenylisoquinoline-N,C 2') iridium(III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]), (acetylacetonato)bis[2,3-bis(4- fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]), (acetylacetonato)bis(3,5- dimethyl-2-phenylpyrazine)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac)]), (acetylacetonato)bis(5- isopropyl-3-methyl-2-phenylpyrazine)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]), (acetylacetonato)bis(2,3,5-triphenylpyrazine)iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2,3,5-triphenylpyrazine)(dipivaloylmethane)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]), (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidine)iridium(III) (abbreviation: [Ir(tBuppm)2(acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidine)iridium(III) (abbreviation: [Ir(dppm)2(acac)]), 2,3,7,8,12,13,17,18-octylethyl-21H,23H-porphine platinum(II) (abbreviation: PtOEP), tris(1,3-diphenyl-1,3-propanedione)(phenanthroline)europium(III) (abbreviation: [Eu(DBM)3(Phen)]), tris[1-(2-thienoyl)-3,3,3-trifluoropropanone](phenanthroline)europium(III) (abbreviation: [Eu(TTA)3(Phen)]), and the like.

[0206] In addition, as the TADF material, for example, fullerene, a derivative thereof, an acridine derivative such as proflavine, eosin, and the like can be given. Further, a metal-containing porphyrin containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd), or the like can be given. As the metal-containing porphyrin, for example, proto-porphyrin-tin fluoride complex (abbreviation: SnF2(Proto IX)), meso-porphyrin-tin fluoride complex (abbreviation: SnF2(Meso IX)), hemato-porphyrin-tin fluoride complex (abbreviation: SnF2(Hemato IX)), copro-porphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complex (abbreviation: SnF2(OEP)), etio-porphyrin-tin fluoride complex (abbreviation: SnF2(Etio I)), octaethylporphyrin-platinum chloride complex (abbreviation: PtCl2OEP), and the like can be given. Also, a heterocyclic compound having a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring such as 2-(diphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ) and the like can be used. In addition, among substances in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded, the donor property of the π-electron rich heteroaromatic ring and the acceptor property of the π-electron deficient heteroaromatic ring are both strong, and the energy difference between S1 and T1 is small, and thus is particularly preferable.

[0207] The electron transport layer 114 is a layer containing a substance (also referred to as an electron transport compound) having high electron transport property. The electron transport layer 114 can use a metal complex such as tris(8-hydroxyquinoline)aluminum (abbreviation: Alq3), tris(4-methyl-8-quinolinolato)aluminum (abbreviation: Almq3), BeBq2, BAlq, bis[2-(2-hydroxyphenyl)benzoxazolato]zinc (abbreviation: Zn(BOX)2), bis[2-(2-hydroxyphenyl)-benzothiazolato]zinc (abbreviation: Zn(BTZ)2), and the like. Further, a heteroaromatic compound such as PBD, TAZ, 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), bathophenanthroline (abbreviation: Bphen), bathocuproin (abbreviation: BCP), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs), and the like can be used. In addition, a high molecular compound such as poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviation: PF-Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy), and the like can be used. The substances described here have an electron mobility of 1 x 10-6cm2 / V s or higher, preferably 1 x 10-5cm2 / V s or higher, more preferably 1 x 10-4cm2 / V s or higher, still more preferably 1 x 10-3cm2 / V s or higher, and even more preferably 1 x 10-2cm2 / V s or higher.-6 cm 2 Vs or more. Note that a substance other than the above substances can be used for the electron-transport layer 114 as long as the substance is a substance whose electron-transport property is higher than its hole-transport property.

[0208] The electron-transport layer 114 can be a single layer or a stack of two or more layers of layers each formed of the above substance.

[0209] The electron-injection layer 115 is a layer containing a substance with high electron-injection property. The electron-injection layer 115 can be formed using an alkali metal or an alkaline earth metal or a compound thereof, such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), lithium oxide (LiO x ) and the like. In addition, a rare earth metal compound such as erbium fluoride (ErF3) can be used. Furthermore, an electron donor can be used for the electron-injection layer 115. As the electron donor, for example, a substance which donates an electron to calcium oxide-aluminum oxide at a high concentration and the like can be given. Alternatively, a substance forming the electron-transport layer 114 described above can be used.

[0210] Alternatively, a composite material in which an organic compound is mixed with an electron donor (donor) can be used for the electron-injection layer 115. Such a composite material has excellent electron-injection and electron-transport properties because of generation of electrons in the organic compound by the electron donor. In this case, the organic compound is preferably a material with excellent properties in transporting generated electrons, and specifically, for example, a substance forming the electron-transport layer 114 described above (a metal complex, a heteroaromatic compound, or the like) can be used. As the electron donor, a substance which has an electron-donating property to the organic compound can be used. Specifically, an alkali metal, an alkaline earth metal, or a rare earth metal is preferable, and lithium, cesium, magnesium, calcium, erbium, ytterbium, and the like can be given. In addition, an alkali metal oxide or an alkaline earth metal oxide is preferable, and lithium oxide, calcium oxide, barium oxide, and the like can be given. Furthermore, a Lewis base such as magnesium oxide can be used. Alternatively, an organic compound such as tetrathiafulvalene (abbreviation: TTF) can be used.

[0211] Each of the above hole-injection layer 111, the hole-transport layer 112, the light-emitting layer 113, the electron-transport layer 114, and the electron-injection layer 115 can be formed by one or a combination of a deposition method (including a vacuum evaporation method), a printing method (e.g., a letter-press method, a gravure method, an intaglio method, a screen printing method, and a flexographic printing method), an inkjet method, a coating method, and the like. In addition, as the above hole-injection layer 111, the hole-transport layer 112, the light-emitting layer 113, the electron-transport layer 114, and the electron-injection layer 115, an inorganic compound such as a quantum dot or a high molecular compound (an oligomer, a dendrimer, a polymer, or the like) can be used in addition to the above materials.

[0212] By the above steps, a light emitting element in which an EL layer is sandwiched between a pair of electrodes can be manufactured.

[0213] The structure according to the present embodiment can be appropriately combined with the structures according to the other embodiments.

[0214] Embodiment 3

[0215] In the present embodiment, a light emitting element having a structure of a plurality of EL layers according to one embodiment of the present application (hereinafter, referred to as a stacked light emitting element) is described.

[0216] The light emitting element according to the present embodiment is a stacked light emitting element having a plurality of EL layers (a first EL layer 202(1) and a second EL layer 202(2)) as shown in FIG. 1, which is sandwiched between a pair of electrodes (a first electrode 201 and a second electrode 204). FIG. 2A

[0217] In the present embodiment, the first electrode 201 is an electrode functioning as an anode, and the second electrode 204 is an electrode functioning as a cathode. In addition, the same structure as that of Embodiment 2 can be employed as the first electrode 201 and the second electrode 204. Further, the plurality of EL layers (the first EL layer 202(1) and the second EL layer 202(2)) can have the same structure as that of the EL layer according to Embodiment 2, or any one of the above EL layers can have the same structure as that of the EL layer according to Embodiment 2. In other words, the first EL layer 202(1) and the second EL layer 202(2) can have the same structure, or can have different structures from each other, and in the case where they have the same structure, the structure according to Embodiment 2 can be applied.

[0218] In addition, the charge generation layer 205 provided between the plurality of EL layers (the first EL layer 202(1) and the second EL layer 202(2)) has a 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 201 and the second electrode 204. In the present embodiment, when a voltage is applied in such a manner that the potential of the first electrode 201 is higher than that of the second electrode 204, electrons are injected from the charge generation layer 205 into the first EL layer 202(1), and holes are injected into the second EL layer 202(2).

[0219] In addition, from the viewpoint of light extraction efficiency, the charge generation layer 205 preferably has a property of transmitting visible light (specifically, the transmittance of visible light of the charge generation layer 205 is 40% or more). In addition, the charge generation layer 205 can function even if its conductivity is less than that of the first electrode 201 or the second electrode 204.

[0220] ​The charge generation layer 205 can have a structure in which an organic compound having a high hole-transport property is added with an electron acceptor (acceptor), or a structure in which an organic compound having a high electron-transport property is added with an electron donor (donor). Alternatively, these two structures can be stacked.

[0221] In the case of a structure in which an organic compound having a high hole-transport property is added with an electron acceptor, as the organic compound having a high hole-transport property, a substance shown in Embodiment 2 as a substance having a high hole-transport property for the hole injection layer 111 and the hole transport layer 112 can be used. For example, an aromatic amine compound such as NPB, TPD, TDATA, MTDATA, BSPB, or the like can be used. The substance described here is mainly a substance in which the hole mobility is 1 x 10 -6 cm 2 Vs or more. Note that a substance other than the above-described substances can be used as long as it is an organic compound in which the hole-transport property is higher than the electron-transport property.

[0222] In addition, as the electron acceptor, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, or the like can be given. In addition, an oxide of a metal belonging to Group 4 to Group 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 a high electron-accepting property. Molybdenum oxide is particularly preferably used because it is stable in the air, has low hygroscopicity, and is easy to handle.

[0223] On the other hand, in the case of a structure in which an organic compound having a high electron-transport property is added with an electron donor, as the organic compound having a high electron-transport property, a substance shown in Embodiment 2 as a substance having a high electron-transport property for the electron transport layer 114 can be used. For example, a metal complex having a quinoline skeleton or a benzoquinoline skeleton, such as Alq, Almq3, BeBq2, BAlq, or the like can be used. In addition to these, a metal complex having an oxazole-based ligand, a thiazole-based ligand, such as Zn(BOX)2, Zn(BTZ)2, or the like can be used. Furthermore, in addition to the metal complex, PBD, OXD-7, TAZ, Bphen, BCP, or the like can be used. The substance described here is mainly a substance in which the electron mobility is 1 x 10 -6 cm 2 Vs or more. Note that a substance other than the above-described substances can be used as long as it is an organic compound in which the electron-transport property is higher than the hole-transport property.

[0224] In addition, alkali metals, alkaline earth metals, rare earth metals, or metals belonging to Groups 2 and 13 of the periodic table, as well as their oxides or carbonates, can be used as electron donors. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide, and cesium carbonate are preferred. Furthermore, organic compounds such as tetrathianaphthacene can also be used as electron donors.

[0225] Furthermore, by using the above-mentioned material to form the charge generation layer 205, the increase in driving voltage caused by stacking EL layers can be suppressed. The charge generation layer 205 can be formed using one or a combination of methods such as vapor deposition (including vacuum vapor deposition), printing (e.g., letterpress printing, gravure printing, photogravure printing, offset printing, screen printing, etc.), inkjet printing, and coating.

[0226] Although this embodiment describes a light-emitting element having two EL layers, however, as FIG. 2B As shown, one aspect of the present invention can also be applied to a light-emitting element that stacks n (where n is 3 or more) EL layers (202(1) to 202(n)). When multiple EL layers are present between a pair of electrodes, as in the light-emitting element according to this embodiment, by providing a charge-generating layer (205(1) to 205(n-1)) between the EL layers, light emission in a high-brightness region can be achieved while maintaining a low current density. Because a low current density can be maintained, a long-life element can be achieved.

[0227] Furthermore, by making the emission colors of each EL layer different, the light-emitting element can emit light of the desired color as a whole. For example, in a light-emitting element with two EL layers, by making the emission colors of the first EL layer and the second EL layer complementary, a light-emitting element that emits white light as a whole can be obtained. Note that "complementary colors" refers to a color relationship that results in a non-color when the colors are mixed. That is, white light can be obtained by mixing light of colors that are complementary. Specifically, a combination of blue emission from the first EL layer and yellow or orange emission from the second EL layer can be given. In this case, it is not necessary for both the blue and yellow (or orange) emission to be fluorescent or phosphorescent; a combination of fluorescent blue emission and phosphorescent yellow (or orange) emission, or vice versa, can also be used.

[0228] The same applies to light-emitting elements with three EL layers. For example, when the first EL layer emits red light, the second EL layer emits green light, and the third EL layer emits blue light, the light-emitting element as a whole can emit white light.

[0229] The structure according to the present embodiment can be implemented in appropriate combination with the structures according to the other embodiments.

[0230] Embodiment 4

[0231] In the present embodiment, a light-emitting device according to one embodiment of the present application is described.

[0232] The light-emitting device described above can be either a passive matrix light-emitting device or an active matrix light-emitting device. Further, the light-emitting element described in the other embodiments can be applied to the light-emitting device described in the present embodiment.

[0233] In the present embodiment, first, the structure of a light-emitting device according to one embodiment of the present application is described with reference to FIG. 1A and FIG. 1B. FIG. 3A and FIG. 3B An active matrix light-emitting device is described.

[0234] FIG. 3A is a top view of a light-emitting device, FIG. 3B is a cross-sectional view taken along the dotted line A-A' in FIG. 3A An active matrix light-emitting device has a pixel portion 302, a driver circuit portion (source line driver circuit) 303, and driver circuit portions (gate line driver circuits) 304a and 304b provided over a device substrate 301. The pixel portion 302, the driver circuit portion 303, and the driver circuit portions 304a and 304b are sealed with a sealing agent 305 between the device substrate 301 and a sealing substrate 306.

[0235] A lead wire 307 for connecting external input terminals that transmit signals (e.g., a video signal, a clock signal, a start signal, or a reset signal) or potentials from the outside to the driver circuit portion 303 and the driver circuit portions 304a and 304b is provided over the device substrate 301. Here, an example in which an FPC (flexible printed circuit) 308 is provided as the external input terminals is shown. Although only the FPC is illustrated here, a printed wiring board (PWB) can be attached to the FPC. The light-emitting device in the present specification includes not only a light-emitting device main body but also a light-emitting device to which the FPC or the PWB is attached.

[0236] Next, a cross-sectional structure is described with reference to FIG. 3B The driver circuit portion 303 and the pixel portion 302, which are a source line driver circuit, are formed over the device substrate 301.

[0237] An example in which the FET 309 and the FET 310 are combined to constitute the driver circuit portion 303 is shown here. The driver circuit portion 303 can be formed of a circuit including unipolar (N-type or P-type) transistors or can be formed of a CMOS circuit including N-type transistors and P-type transistors. In this embodiment, a driver-on-substrate type in which the driver circuit is formed on a substrate is shown, but it is not necessarily so and the driver circuit can be formed outside the substrate without being formed on the substrate.

[0238] Further, the pixel portion 302 includes a switching FET (not shown) and a current control FET 312, and a wiring (a source electrode or a drain electrode) of the current control FET 312 is electrically connected to the first electrodes (anodes) (313a, 313b) of the light emitting elements 317a and 317b. Further, although an example in which the pixel portion 302 is constituted using two FETs (the switching FET and the current control FET 312) is shown in this embodiment, it is not limited thereto. For example, the pixel portion 302 can have a structure in which three or more FETs and a capacitor element are combined.

[0239] As the FETs 309, 310, and 312, for example, staggered transistors or inverted staggered transistors can be appropriately used. As a semiconductor material that can be used for the FETs 309, 310, and 312, for example, Group 13 semiconductors, Group 14 (silicon, etc.) semiconductors, compound semiconductors, oxide semiconductors, and organic semiconductors can be used. Further, there is no particular limitation on the crystallinity of the semiconductor material, and for example, an amorphous semiconductor film or a crystalline semiconductor film can be used. In particular, the FETs 309, 310, and 312 preferably use an oxide semiconductor. As the oxide semiconductor, for example, an In-Ga oxide, an In-M-Zn oxide (M is Al, Ga, Y, Zr, La, Ce, Hf, or Nd), or the like can be given. As the FETs 309, 310, and 312, for example, an oxide semiconductor material having an energy gap of 2 eV or more, preferably 2.5 eV or more, and more preferably 3 eV or more is used, whereby the off-state current of the transistor can be reduced.

[0240] Further, the first electrodes (313a, 313b) have a structure in which a conductive film (320a, 320b) for optical adjustment is layered. For example, as shown in FIG. 6A, the thicknesses of the conductive films 320a and 320b are different from each other when the wavelengths of the light extracted from the light emitting element 317a and the light extracted from the light emitting element 317b are different from each other. Note that the insulator 314 is formed so as to cover the end portions of the first electrodes (313a, 313b). Here, the insulator 314 is formed using a positive photosensitive acrylic resin. Further, in this embodiment, the first electrodes (313a, 313b) are used as anodes. FIG. 3B In this embodiment, the first electrodes (313a, 313b) are used as anodes.

[0241] The upper end portion or the lower end portion of the insulator 314 is preferably formed into a curved surface having a curvature. By forming the insulator 314 into the above shape, the coverage of a film formed on the insulator 314 can be improved. As a material of the insulator 314, a negative photosensitive resin or a positive photosensitive resin can be used, and the material is not limited to an organic compound, and an inorganic compound such as silicon oxide, silicon oxynitride, silicon nitride, or the like can be used.

[0242] The EL layer 315 is formed over the first electrode 313, and the second electrode 316 is formed over the EL layer 315. The EL layer 315 is provided with at least a light-emitting layer, and a light-emitting element 317 formed of the first electrode 313, the EL layer 315, and the second electrode 316 has a structure in which an end portion of the EL layer 315 is covered with the second electrode 316. The structure of the EL layer 315 can be the same as or different from the single-layer structure or the stacked structure described in Embodiment 2 or Embodiment 3. Further, the above structure can be different depending on the light-emitting element.

[0243] As a material for the first electrode 313, the EL layer 315, and the second electrode 316, the materials described in Embodiment 2 can be used. Further, the first electrode 313 of the light-emitting element 317 is electrically connected to the lead wire 307 in a region 321 and input with an external signal through the FPC 308. Furthermore, the second electrode 316 of the light-emitting element 317 is electrically connected to the lead wire 323 in a region 322, although not illustrated, and input with an external signal through the FPC 308.

[0244] Although only two light-emitting elements 317 are illustrated in the cross-sectional view of FIG. 8A, FIG. 3B Although only two light-emitting elements 317 are illustrated in the cross-sectional view of FIG. 8A,

[0245] Further, the light emitting elements 317a, 317b are provided in a space 318 surrounded by the element substrate 301, the sealing substrate 306, and the sealing material 305 by attaching the sealing substrate 306 to the element substrate 301 with the sealing material 305.

[0246] Further, a color layer (color filter) 324 is provided on the sealing substrate 306, and a black layer (black matrix) 325 is provided between adjacent color layers. One or both of the adjacent color layers (color filters) 324 can be provided so as to overlap with the black layer (black matrix) 325 in part thereof. Note that light emission from the light emitting elements 317a, 317b is extracted to the outside through the color layer (color filter) 324.

[0247] The space 318 can be filled with an inert gas such as nitrogen or argon, or the sealing material 305. When attachment is performed by applying a sealing material, UV treatment or heat treatment or a combination of these treatments is preferably performed.

[0248] An epoxy-based resin or a glass frit is preferably used as the sealing material 305. Further, these materials are preferably materials that transmit as little moisture and oxygen as possible. Further, as the sealing substrate 306, a plastic substrate formed of FRP (Fiber-Reinforced Plastics), PVF (polyvinyl fluoride), polyester, an acrylic resin, or the like can be used in addition to a glass substrate and a quartz substrate. From the viewpoint of adhesion, in the case where a glass frit is used as the sealing material, a glass substrate is preferably used as the element substrate 301 and the sealing substrate 306.

[0249] The FET electrically connected to the light emitting element can have a structure different from that of the FET 326, the FET 327, and the FET 328 shown in FIG. 1A. FIG. 3B FIG. 3C As shown in FIG. 1B, the FET 326, the FET 327, and the FET 328 can be provided in the element substrate 301. FIG. 3C

[0250] As described above, an active matrix light emitting device can be obtained.

[0251] The light emitting device of one embodiment of the present application can be used for a passive matrix light emitting device, and is not limited to the active matrix light emitting device described above.

[0252] FIG. 4A and FIG. 4B A passive matrix light emitting device is described. FIG. 4A A top view of a passive matrix light emitting device is described, FIG. 4B ​​A cross-sectional view of a passive matrix light emitting device is shown.

[0253] As shown in FIG. 1A, a light emitting element 105 is formed over a substrate 101. The light emitting element 105 includes a first electrode 102, an EL layer (103a, 103b, 103c), and a second electrode 104. The first electrode 102 is in an island shape, and a plurality of first electrodes 102 are arranged in a stripe shape in a lateral direction (a direction perpendicular to the plane of the drawing sheet) of the substrate 101. FIG. 4A The first electrode 102 is formed of a conductive material such as indium tin oxide (ITO) or aluminum (Al). The first electrode 102 is formed by a deposition method such as a vacuum deposition method or a sputtering method. FIG. 4B The EL layer (103a, 103b, 103c) is formed over the first electrode 102. The EL layer (103a, 103b, 103c) is formed by a deposition method such as a vacuum deposition method or a sputtering method. FIG. 4A The second electrode 104 is formed over the EL layer (103a, 103b, 103c). The second electrode 104 is formed by a deposition method such as a vacuum deposition method or a sputtering method. FIG. 4B The second electrode 104 is formed of a conductive material such as indium tin oxide (ITO) or aluminum (Al). The second electrode 104 is formed by a deposition method such as a vacuum deposition method or a sputtering method.

[0254] The insulating film 106 is formed over the second electrode 104. The insulating film 106 is formed by a deposition method such as a vacuum deposition method or a sputtering method. FIG. 4A The insulating film 106 is formed over the second electrode 104. The insulating film 106 is formed by a deposition method such as a vacuum deposition method or a sputtering method. FIG. 4B A cross-sectional view of a passive matrix light emitting device is shown.

[0255] The second electrode 104 is formed over the EL layer (103a, 103b, 103c). The second electrode 104 is formed by a deposition method such as a vacuum deposition method or a sputtering method.

[0256] Note that the sealing method can be employed as in the case of the active matrix light emitting device, and thus a description thereof is omitted here.

[0257] A passive matrix light emitting device can be obtained by the above steps.

[0258] For example, in this specification and the like, a transistor or a light-emitting element can be formed using a variety of substrates. There is no particular limitation on the kind of the substrate. As an example of the substrate, a semiconductor substrate (e.g., a single crystal substrate or a silicon substrate), an SOI substrate, a glass substrate, a quartz substrate, a plastic substrate, a metal substrate, a stainless steel substrate, a substrate including a stainless steel foil, a tungsten substrate, a substrate including a tungsten foil, a flexible substrate, a bonding film, paper or a base material film including a fibrous material, or the like can be used, for example. As an example of the glass substrate, barium borosilicate glass, aluminoborosilicate glass, or sodium calcium glass is given. As the flexible substrate, the bonding film, the base material film, or the like, the following examples can be given. For example, plastic typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or polytetrafluoroethylene (PTFE) can be given. Alternatively, a synthetic resin such as acrylic can be given. Alternatively, polypropylene, polyester, polyvinyl fluoride, polyvinyl chloride, or the like can be given. Alternatively, polyamide, polyimide, aramid, epoxy, an inorganic vapor-deposited film, paper, or the like can be given. In particular, by using a semiconductor substrate, a single crystal substrate, or an SOI substrate, a transistor with small unevenness in characteristics, size, or shape, high current supply capability, and small size can be manufactured. When a circuit is formed using the above transistor, low power consumption of the circuit or high integration of the circuit can be achieved.

[0259] In addition, a flexible substrate can be used as the substrate, and a transistor or a light-emitting element can be directly formed over the flexible substrate. Alternatively, a separation layer can be provided between a substrate and a transistor or a light-emitting element. The separation layer can be used when part or all of a semiconductor device is manufactured over the separation layer and then separated from the substrate and transferred to another substrate. At this time, a transistor or a light-emitting element can be transferred to a substrate with low heat resistance or a flexible substrate. In addition, as the above separation layer, an inorganic film stack of a tungsten film and a silicon oxide film, a structure in which an organic resin film such as polyimide is formed over a substrate, or the like can be used, for example.

[0260] That is, a transistor or a light-emitting element can be formed using one substrate and then transferred to another substrate. As examples of the substrate to which a transistor or a light-emitting element is transferred, a substrate over which a transistor or a light-emitting element can be formed as described above, a paper substrate, a glassine substrate, an aramid film substrate, a polyimide film substrate, a stone substrate, a wood substrate, a cloth substrate (including natural fibers (silk, cotton, and hemp), synthetic fibers (nylon, polyurethane, and polyester), or regenerated fibers (acetate fiber, cupra fiber, rayon, and regenerated polyester), and the like), a leather substrate, a rubber substrate, and the like can be given. By using the above substrate, a transistor with good characteristics, a transistor with low power consumption, a device that is not easily broken, improvement in heat resistance, weight reduction, or thinning can be achieved.

[0261] The structure according to the present embodiment can be implemented in appropriate combination with the structures according to the other embodiments.

[0262] Embodiment 5

[0263] In the present embodiment, examples of various electronic devices and automobiles each of which is completed using the light-emitting device according to one embodiment of the present application are described.

[0264] As electronic devices to which the light-emitting device is applied, for example, a television device (also referred to as a television or a television receiver), a monitor for a computer or the like, a digital camera, a digital video camera, a digital photo frame, a mobile phone (also referred to as a mobile phone device or a mobile phone apparatus), a portable game console, a portable information terminal, an audio reproducing device, a large-sized game machine such as a pinball machine, and the like can be given. FIG. 5A1 FIG. 5A2 FIG. 5B FIG. 5C FIG. 5D1 FIG. 5D2 FIG. 5D3 Specific examples of these electronic devices are described below.

[0265] FIG. 5A1 An example of a television device is described. In a television device 7100, a frame 7101 is assembled with a display portion 7103. An image can be displayed by the display portion 7103, and a touch panel (input and output device) provided with a touch sensor (input device) can be used. Further, the light-emitting device according to one embodiment of the present application can be used for the display portion 7103. A structure in which the frame 7101 is supported by a stand 7105 is shown here.

[0266] The television device 7100 can be operated by operating switches provided in the frame 7101 or a remote control 7110 provided separately as shown in FIG. 8. FIG. 5A2 The television device 7100 can be operated by operating switches provided in the frame 7101 or a remote control 7110 provided separately as shown in FIG. 8.

[0267] The television device 7100 has a structure provided with a receiver, a modem, and the like. With the receiver, general television broadcasting can be received. Further, with the modem connected to a communication network by a wired or wireless method, one-way (from a sender to a receiver) or two-way (between a sender and a receiver or between receivers, or the like) information communication can be performed.

[0268] FIG. 5B ​​​​​​A computer includes a main body 7201, a frame body 7202, a display portion 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, and the like. The computer can be manufactured by applying the light-emitting device of one embodiment of the present application to the display portion 7203 thereof. Further, the display portion 7203 can be a touch panel (input and output device) provided with a touch sensor (input device).

[0269] FIG. 5C A smart watch includes a frame body 7302, a display portion 7304, an operation button 7311, an operation button 7312, a connection terminal 7313, a wrist band 7321, a band buckle 7322, and the like.

[0270] The display portion 7304 included in the frame body 7302 serving as a bezel portion has a display region with a non-rectangular shape. The display portion 7304 can display an icon 7305 indicating time and an icon 7306, and the like. Further, the display portion 7304 can be a touch panel (input and output device) provided with a touch sensor (input device).

[0271] FIG. 5C The illustrated smart watch can have a variety of functions. For example, the smart watch can have a function of displaying a variety of information (a still image, a moving image, a textual image, and the like) on the display portion, a touch panel function, a function of displaying the date, time, and the like, a function of controlling a process with the use of a variety of software (a program), a wireless communication function, a function of transmitting and receiving a variety of data with the use of a wireless communication function, and a function of reading a program or data stored in a storage medium and causing the program or data to be displayed on the display portion, and the like.

[0272] The inside of the frame body 7302 can have a speaker, a sensor (including a function of measuring, for example, a force, a displacement, a position, a speed, an acceleration, an angular velocity, an angular frequency, a distance, light, liquid, magnetism, temperature, a chemical substance, sound, time, hardness, an electric field, a current, electricity, an electric power, a radiation, a flow rate, humidity, a slope, a vibration, an odor, or infrared rays), a microphone, and the like. In addition, the smart watch can be manufactured by applying the light-emitting device to the display portion 7304 thereof.

[0273] FIG. 5D1 、 FIG. 5D2 and FIG. 5D3 An example of a mobile phone (including a smartphone) is illustrated. The mobile phone 7400 includes a display portion 7402, a microphone 7406, a speaker 7405, a camera 7407, an external connection port 7404, an operation button 7403, and the like in a frame body 7401. When a light-emitting element of one embodiment of the present application is formed in a substrate with flexibility to manufacture a light-emitting device, it can be applied to, for example,FIG. 5D1 The display portion 7402 has a curved surface as illustrated.

[0274] FIG. 5D1 The mobile phone 7400 illustrated can input information by touching the display portion 7402 with a finger or the like. Furthermore, the mobile phone 7400 can make a call or write an e-mail message by touching the display portion 7402 with a finger or the like.

[0275] The screen of the display portion 7402 has mainly three modes: a display mode in which an image is mainly displayed, an input mode in which information is mainly input by characters or the like, and a display and input mode in which both of the display mode and the input mode are mixed.

[0276] For example, in the case of making a call or writing an e-mail message, the display portion 7402 is set to the character input mode in which characters are mainly input, and input operation of characters displayed on the screen is performed. In this case, it is preferable that a keyboard or number buttons be displayed on most of the screen of the display portion 7402.

[0277] In addition, by providing a detection means such as a gyroscope or an acceleration sensor in the mobile phone 7400, the direction (portrait or landscape) of the mobile phone 7400 is determined, and thus the screen display of the display portion 7402 can be automatically switched.

[0278] The screen mode is switched by touching the display portion 7402 or operating the operation buttons 7403 of the housing 7401. Alternatively, the screen mode can be switched depending on the type of an image displayed on the display portion 7402. For example, when an image signal displayed on the display portion is data of a dynamic image, the screen mode is switched to the display mode, and when the image signal is text data, the screen mode is switched to the input mode.

[0279] In addition, when no touch operation input of the display portion 7402 is made for a certain period of time by obtaining a signal of a light sensor of the display portion 7402 in the input mode, the display mode can be switched to the input mode.

[0280] The display portion 7402 can also be used as an image sensor. For example, a palm print, a fingerprint, or the like can be imaged by touching the display portion 7402 with a palm or a finger, so that personal identification can be performed. In addition, a finger vein, a palm vein, or the like can be imaged by using a backlight or a light source for a sensor which emits near-infrared light for the display portion.

[0281] Further, as another structure of a mobile phone (including a smartphone), a mobile phone having a structure as illustrated in FIGS. 1A and IB can be used. FIG. 5D2 and FIG. 5D3 a mobile phone having a structure as illustrated in FIGS. 1A and IB can be used.

[0282] In the mobile phone having the structure shown in FIG. 5D2 and FIG. 5D3 , text information or image information or the like is displayed not only on the first face 7501(1), the first face 7501(2) of the frame body 7500(1), the frame body 7500(2) but also on the second face 7502(1), the second face 7502(2). With this structure, the user can easily confirm the text information or the image information or the like displayed on the second face 7502(1), the second face 7502(2) or the like in a state where the mobile phone is stored in a pocket of a coat.

[0283] As electronic devices to which the light-emitting device is applied, a foldable portable information terminal shown in FIGS. 6A-6C can be given. FIG. 6A A portable information terminal 9310 is shown in an unfolded state. FIG. 6B A portable information terminal 9310 is shown in a state halfway from one of an unfolded state and a folded state to the other state. FIG. 6C A portable information terminal 9310 is shown in a folded state. The portable information terminal 9310 is good in portability in the folded state and is high in display overview in the unfolded state because of a large display region with seamless splicing.

[0284] A display portion 9311 is supported by three frame bodies 9315 connected by a hinge portion 9313. Further, the display portion 9311 can be a touch panel (input and output device) provided with a touch sensor (input device). Further, the display portion 9311 is bent between two frame bodies 9315 by the hinge portion 9313, whereby the portable information terminal 9310 can be reversibly changed from the unfolded state to the folded state. The light-emitting device of one embodiment of the present application can be used for the display portion 9311. A display region 9312 in the display portion 9311 is a display region on a side surface of the portable information terminal 9310 in the folded state. In the display region 9312, an information icon or a shortcut of application software or a program frequently used can be displayed, and confirmation of information or activation of software can be smoothly performed.

[0285] FIG. 7A and FIG. 7B A car to which the light-emitting device is applied is shown. That is, the light-emitting device can be formed integrally with the car. Specifically, the light-emitting device can be applied to a lamp 5101 (including a rear portion of a vehicle body), a hub 5102 of a tire, a part or the whole of a door 5103, or the like on an outer side of the car shown in FIG. 7A . Further, the light-emitting device can be applied to a lamp 5101 (including a rear portion of a vehicle body), a hub 5102 of a tire, a part or the whole of a door 5103, or the like on an outer side of the car shown in FIG. 7BThe examples shown include the interior display unit 5104, steering wheel 5105, gearshift lever 5106, seat 5107, and rearview mirror 5108. Additionally, the lighting device can also be applied to a portion of the glass window.

[0286] As described above, the light-emitting device according to one aspect of the present invention can be used to obtain electronic devices or automobiles. The applicable electronic devices or automobiles are not limited to those shown in this embodiment, and can be applied in various fields.

[0287] The structure shown in this embodiment can be implemented by appropriately combining it with the structures shown in other embodiments.

[0288] Implementation Method 6

[0289] In this embodiment, refer to FIGS. 8A-8D The structure of a lighting device manufactured using a light-emitting element according to one aspect of the present invention is described.

[0290] FIGS. 8A-8D An example of a cross-sectional view of a lighting device is shown. FIG. 8A and FIG. 8B It is a bottom-emitting illumination device that extracts light from one side of the substrate, and FIG. 8C and FIG. 8D It is a top-emitting type illumination device that extracts light from one side of a sealed substrate.

[0291] FIG. 8A The illumination device 4000 shown includes a light-emitting element 4002 on a substrate 4001. Additionally, the illumination device 4000 includes a substrate 4003 with irregularities on the outer side of the substrate 4001. The light-emitting element 4002 includes a first electrode 4004, an EL layer 4005, and a second electrode 4006.

[0292] The first electrode 4004 is electrically connected to the electrode 4007, and the second electrode 4006 is electrically connected to the electrode 4008. Alternatively, an auxiliary wiring 4009 electrically connected to the first electrode 4004 may be provided. Furthermore, an insulating layer 4010 is formed on the auxiliary wiring 4009.

[0293] Substrate 4001 and sealing substrate 4011 are bonded together by sealing material 4012. Additionally, a desiccant 4013 is preferably disposed between sealing substrate 4011 and light-emitting element 4002. Because substrate 4003 has such... FIG. 8A The unevenness shown can improve the efficiency of extracting light generated in the light-emitting element 4002.

[0294] In addition, such as FIG. 8B As shown in the lighting device 4100, a diffuser plate 4015 can also be provided on the outside of the substrate 4001 instead of the substrate 4003.

[0295] FIG. 8C The illumination device 4200 illustrated includes a light-emitting element 4202 over a substrate 4201. The light-emitting element 4202 includes a first electrode 4204, an EL layer 4205, and a second electrode 4206.

[0296] The first electrode 4204 is electrically connected to an electrode 4207, and the second electrode 4206 is electrically connected to an electrode 4208. In addition, an auxiliary wiring 4209 electrically connected to the second electrode 4206 can be provided. In addition, an insulating layer 4210 can be provided under the auxiliary wiring 4209.

[0297] The substrate 4201 and a sealing substrate 4211 having unevenness are bonded by a sealing material 4212. In addition, a barrier film 4213 and a planarization film 4214 can be provided between the sealing substrate 4211 and the light-emitting element 4202. Since the sealing substrate 4211 has unevenness as illustrated in FIG. 8C Therefore, the efficiency of extracting light generated in the light-emitting element 4202 can be improved.

[0298] In addition, as illustrated in FIG. 8D Instead of the sealing substrate 4211, a diffusion plate 4215 can be provided over the light-emitting element 4202, as illustrated in the illumination device 4300.

[0299] The EL layer 4005 and 4205 illustrated in this embodiment can use an organic metal complex of one embodiment of the present application. At this time, an illumination device with low power consumption can be provided.

[0300] The structure illustrated in this embodiment can be appropriately combined with the structures illustrated in other embodiments.

[0301] Embodiment 7

[0302] In this embodiment, reference is made to FIG. 9 An illumination device which is an example of an application example of a light-emitting device of one embodiment of the present application is described.

[0303] FIG. 9 is an example in which a light-emitting device is used for an indoor illumination device 8001. In addition, since a light-emitting device can be made large in area, a large-area illumination device can be formed. Furthermore, an illumination device 8002 in which a light-emitting region has a curved surface can be formed by using a frame having a curved surface. The light-emitting element included in the light-emitting device illustrated in this embodiment is thin-film-shaped, so that the degree of freedom in frame design is high. Thus, an illumination device which can correspond to various designs can be formed. Furthermore, an illumination device 8003 can be provided on a wall surface in a room.

[0304] By using a light-emitting device for a part of indoor furniture other than the above, an illumination device having the function of furniture can be provided.

[0305] As described above, a variety of lighting devices to which the light-emitting device is applied can be obtained. Further, such a lighting device is included in one embodiment of the present application.

[0306] The structure described in this embodiment mode can be implemented in appropriate combination with the structures described in other embodiment modes.

[0307] Embodiment 8

[0308] In this embodiment, reference is made to FIGS. 10A-14 A touch screen including a light-emitting element of one embodiment of the present application or a light-emitting device of one embodiment of the present application is described.

[0309] FIG. 10A and FIG. 10B is a perspective view of a touch screen 2000. Note that, in FIG. 10A and FIG. 10B , typical constituent elements of the touch screen 2000 are shown for easy understanding.

[0310] The touch screen 2000 includes a display panel 2501 and a touch sensor 2595 (see FIG. 10B ). The touch screen 2000 also includes a substrate 2510, a substrate 2570, and a substrate 2590.

[0311] The display panel 2501 includes a plurality of pixels over the substrate 2510 and a plurality of wirings 2511 which can supply a signal to the pixels. The plurality of wirings 2511 are led to the outer peripheral portion of the substrate 2510, and part of them forms a terminal 2519. The terminal 2519 is electrically connected to the FPC 2509 (1).

[0312] The substrate 2590 includes the touch sensor 2595 and a plurality of wirings 2598 which are electrically connected to the touch sensor 2595. The plurality of wirings 2598 are led to the outer peripheral portion of the substrate 2590, and part of them forms a terminal 2599. The terminal 2599 is electrically connected to the FPC 2509 (2). Note that, in FIG. 10B , the electrode and the wiring of the touch sensor 2595 provided on the back surface side (the side opposite to the substrate 2510) of the substrate 2590 are shown by solid lines for easy understanding.

[0313] As the touch sensor 2595, a capacitive touch sensor can be used, for example. As the capacitive touch sensor, a surface capacitive touch sensor, a projected capacitive touch sensor, or the like can be given.

[0314] As examples of projected capacitive touch sensors, there are self-capacitive touch sensors and mutual capacitive touch sensors, which are mainly distinguished by differences in their driving methods. When using a mutual capacitive touch sensor, multi-point detection can be performed simultaneously, making it the preferred choice.

[0315] First, refer to FIG. 10A The use of projected capacitive touch sensors will be explained. Projected capacitive touch sensors can be applied to various sensors capable of detecting the proximity or contact of objects such as fingers.

[0316] The projected capacitive touch sensor 2595 has electrodes 2591 and 2592. Electrodes 2591 and 2592 are electrically connected to different wires in a plurality of wires 2598. For example... FIG. 10B and FIG. 11A As shown, electrode 2592 has a shape in which the corners of a plurality of quadrilaterals arranged continuously in one direction are interconnected by wiring 2594. Electrode 2591 also has a shape in which the corners of a plurality of quadrilaterals are connected, but the connection direction of electrode 2591 intersects the connection direction of electrode 2592. Note that the connection direction of electrode 2591 and the connection direction of electrode 2592 do not necessarily need to intersect, and the angle between them can be greater than 0 degrees and less than 90 degrees.

[0317] Preferably, the area of ​​the intersection between the wiring 2594 and the electrode 2592 should be minimized. This reduces the area of ​​the region without electrodes, thereby reducing transmittance non-uniformity. Consequently, brightness non-uniformity of light transmitted through the touch sensor 2595 can be reduced.

[0318] Furthermore, the shapes of electrodes 2591 and 2592 are not limited to this and can have various shapes. For example, multiple electrodes 2591 can be arranged in a manner with as few gaps as possible, and multiple electrodes 2592 can be arranged with an insulating layer in between. In this case, by providing a virtual electrode that is electrically insulated from adjacent electrodes 2592, the area of ​​regions with different transmittances can be reduced, which is preferred.

[0319] Next, refer to FIG. 11B and FIG. 11A A detailed description of the Touchscreen 2000 is provided. FIG. 10A Equivalent to FIG. 11A The cross-sectional view between the dotted and dashed lines X1 and X2 is shown.

[0320] The touch screen 2000 includes a touch sensor 2595 and a display panel 2501.

[0321] The touch sensor 2595 includes electrodes 2591 and 2592 arranged in a staggered shape in contact with the substrate 2590, an insulating layer 2593 covering the electrodes 2591 and 2592, and a wiring 2594 electrically connecting adjacent electrodes 2591. Further, the electrodes 2592 are provided between adjacent electrodes 2591.

[0322] The electrodes 2591 and 2592 can be formed using a light-transmissive conductive material. As the light-transmissive conductive material, a conductive oxide such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide to which gallium is added, or the like can be used. Alternatively, a graphene compound can be used. Further, when a graphene compound is used, it can be formed, for example, by reduction of a film-shaped graphene oxide. As a reduction method, a method of performing heating, a method of irradiating laser light, or the like can be employed.

[0323] For example, after a film of a light-transmissive conductive material is formed on the substrate 2590 by a sputtering method, the electrodes 2591 and 2592 can be formed by removing unnecessary portions by various patterning techniques such as a photolithography method.

[0324] As a material for the insulating layer 2593, for example, in addition to an acrylic resin, an epoxy resin, a resin having a siloxane bond, an inorganic insulating material such as silicon oxide, silicon oxynitride, aluminum oxide, or the like can be used.

[0325] The adjacent electrodes 2591 are electrically connected by the wiring 2594 formed in a portion of the insulating layer 2593. Alternatively, a material having higher conductivity than the material used for the electrodes 2591 and 2592 is preferably used for the wiring 2594 because the resistance can be reduced.

[0326] The wiring 2598 is electrically connected to the electrodes 2591 or 2592. A portion of the wiring 2598 is used as a terminal. The wiring 2598 can be formed using, for example, a metal material such as aluminum, gold, platinum, silver, nickel, titanium, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, or the like, or an alloy material containing the metal material.

[0327] The wiring 2598 is electrically connected to the FPC 2509(2) by a terminal 2599. The terminal 2599 can be formed using various anisotropic conductive films (ACF: Anisotropic Conductive Film), anisotropic conductive pastes (ACP: Anisotropic Conductive Paste), or the like.

[0328] An adhesive layer 2597 is provided in contact with the wiring 2594. In other words, the touch sensor 2595 is attached so as to overlap the display panel 2501 with the adhesive layer 2597 interposed therebetween. Further, the surface of the display panel 2501 in contact with the adhesive layer 2597 is preferably subjected to surface treatment such as rubbing treatment or primer treatment. FIG. 11AThe substrate 2570 can be included as illustrated, but need not be included.

[0329] The adhesive layer 2597 has light-transmitting properties. For example, a thermosetting resin, an ultraviolet-curing resin, specifically, an acrylic resin, a urethane resin, an epoxy resin, or a silicone resin, or the like can be used.

[0330] FIG. 11A The display panel 2501 illustrated includes a plurality of pixels and a driver circuit configured in a matrix between the substrate 2510 and the substrate 2570. Further, each pixel includes a light-emitting element and a pixel circuit that drives the light-emitting element.

[0331] In FIG. 11A A pixel 2502R is illustrated as one example of the pixel of the display panel 2501, and a scan line driver circuit 2503g is illustrated as one example of the driver circuit.

[0332] The pixel 2502R includes a light-emitting element 2550R and a transistor 2502t that can supply electric power to the light-emitting element 2550R.

[0333] An insulating layer 2521 covers the transistor 2502t. The insulating layer 2521 has a function of planarizing unevenness due to the transistor and the like that have been formed. Further, the insulating layer 2521 can have a function of suppressing diffusion of impurities. At this time, it is preferable because the reliability of the transistor and the like can be suppressed from being reduced due to diffusion of impurities.

[0334] The light-emitting element 2550R is electrically connected to the transistor 2502t through a wiring. Further, one electrode of the light-emitting element 2550R is directly connected to the wiring. Further, an end portion of the one electrode of the light-emitting element 2550R is covered with an insulator 2528.

[0335] The light-emitting element 2550R includes an EL layer between a pair of electrodes. Further, a coloring layer 2567R is provided at a position overlapping the light-emitting element 2550R, and part of light emitted from the light-emitting element 2550R transmits through the coloring layer 2567R and is emitted in the direction of the arrow illustrated in the drawing. Further, a light-blocking layer 2567BM is provided at an end portion of the coloring layer, and a sealing layer 2560 is included between the light-emitting element 2550R and the coloring layer 2567R.

[0336] When the sealing layer 2560 is provided in a direction in which light from the light-emitting element 2550R is extracted, the sealing layer 2560 preferably has light-transmitting properties. Further, the refractive index of the sealing layer 2560 is preferably higher than that of air.

[0337] The scan line driving circuit 2503g includes a transistor 2503t and a capacitor 2503c. Furthermore, the driving circuit can be formed on the same substrate using the same manufacturing process as the pixel circuit. Therefore, similar to the transistor 2502t in the pixel circuit, the transistor 2503t in the driving circuit (scan line driving circuit 2503g) is also covered by an insulating layer 2521.

[0338] In addition, wiring 2511 is provided to supply signals to transistor 2503t. Furthermore, terminals 2519 are provided in contact with wiring 2511. Terminals 2519 are electrically connected to FPC 2509(1), which has the function of supplying signals such as image signals and synchronization signals. A printed circuit board (PWB) may also be mounted on FPC 2509(1).

[0339] Although shown FIG. 11A The display panel 2501 shown includes a bottom-gate transistor, but the transistor structure is not limited to this; various transistor structures can also be used. Furthermore, in FIG. 11B In the transistors 2502t and 2503t shown, a semiconductor layer containing an oxide semiconductor can be used as the channel region. Alternatively, a semiconductor layer containing amorphous silicon or a semiconductor layer containing polycrystalline silicon that has been crystallized by laser annealing or the like can also be used as the channel region.

[0340] also, FIG. 11A Showing will be with FIG. 11A The structure shown illustrates a bottom-gate transistor versus a top-gate transistor used in the display panel 2501. Furthermore, even if the transistor structure is changed, the type of semiconductor layer that can be used in the channel region remains the same.

[0341] FIG. 11A The touchscreen 2000 shown is as follows FIG. 11A The preferred embodiment includes an anti-reflection layer 2567p on the surface of the side from which light from the pixel is emitted to the outside, in a manner that at least overlaps with the pixel. For example, a circular polarizer can be used as the anti-reflection layer 2567p.

[0342] As FIG. 12A The substrates 2510, 2570, and 2590 shown can, for example, use a water vapor permeability of 1×10⁻⁶. -5 g / (m 2 For days or less, 1×10 is preferred. -6 g / (m 2 Flexible materials with a coefficient of thermal expansion of approximately 1000 m (500 m). Furthermore, these substrates are preferably formed using materials with approximately the same coefficient of thermal expansion. For example, materials with a linear expansion coefficient of 1 × 10⁻⁶ can be cited. -3 / K or less, preferably 5×10-5 / K or less, preferably 1×10 -5 Materials below / K.

[0343] Next, refer to FIG. 12B and FIG. 11A to and FIG. 11B and FIG. 12A The structure of touchscreen 2000 is different from that of touchscreen 2000. Note that touchscreen 2000' can be used as a touchscreen in the same way as touchscreen 2000.

[0344] FIG. 12B and FIG. 11A This is a cross-sectional view of the Touchscreen 2000. FIG. 11B and FIG. 12A The touchscreen 2000 shown is... FIG. 12A and FIG. 12A The difference between the touchscreen 2000 shown is the position of the touch sensor 2595 relative to the display panel 2501. Here, only the differences will be described in detail; for parts that can use the same structure, the description of the touchscreen 2000 will be used as a reference.

[0345] The color layer 2567R is located at the position overlapping with the light-emitting element 2550R. FIG. 12A The light from the light-emitting element 2550R is emitted in the direction where the transistor 2502t is located. That is, a portion of the light from the light-emitting element 2550R passes through the coloring layer 2567R and is emitted towards... FIG. 12A The arrow in the image is directed in the direction of the light. Furthermore, a light-shielding layer 2567BM is provided at the end of the coloring layer 2567R.

[0346] Furthermore, the touch sensor 2595 is positioned on the display panel 2501 closer to the transistor 2502t than the light-emitting element 2550R (see reference). FIG. 12B ).

[0347] The adhesive layer 2597 contacts the substrate 2510 included in the display panel 2501, when using... FIG. 13A In the structure shown, the display panel 2501 is bonded to the touch sensor 2595. Note that a structure in which the display panel 2501 and the touch sensor 2595 are bonded using an adhesive layer 2597 can also be used without a substrate 2510 between them.

[0348] Similar to the case of the touchscreen 2000, transistors of various structures can be applied to the display panel 2501 when using the touchscreen 2000'. Furthermore, in FIG. 13B The image shows a case where a bottom-gate transistor is used, but as... FIG. 13A As shown, top-gate transistors can also be used.

[0349] Next, referring to FIG. 13A and FIG. 13A an example of a driving method of a touch screen will be described.

[0350] FIG. 13A is a block diagram showing the structure of a mutual capacitance type touch sensor. In FIG. 13B , a pulse voltage output circuit 2601, a current detection circuit 2602 are shown. In addition, in FIG. 13A , six wirings X1 to X6 are shown as electrodes 2621 to which a pulse voltage is applied, and six wirings Y1 to Y6 are shown as electrodes 2622 which detect a change in current. Further, in FIG. 13B , a capacitor 2603 is shown which is formed by the electrodes 2621 and the electrodes 2622 overlapping each other. Note that the functions of the electrodes 2621 and the electrodes 2622 can be interchanged.

[0351] The pulse voltage output circuit 2601 is a circuit for sequentially applying a pulse voltage to the wirings X1 to X6. When a pulse voltage is applied to the wirings X1 to X6, an electric field is generated between the electrodes 2621 and the electrodes 2622 which form the capacitor 2603. When the electric field generated between the electrodes is shielded or the like, a mutual capacitance change of the capacitor 2603 occurs, and by utilizing this change, proximity or contact of a detection object can be detected.

[0352] The current detection circuit 2602 is a circuit for detecting a change in current of the wirings Y1 to Y6 due to a mutual capacitance change of the capacitor 2603. In the wirings Y1 to Y6, if there is no proximity or contact of a detection object, there is no change in the detected current value, on the other hand, in a case where the mutual capacitance decreases due to proximity or contact of a detection object which is detected, a change in which the current value decreases is detected. In addition, the current can be detected by an integrating circuit or the like.

[0353] Next, FIG. 13B shows FIG. 13A a timing chart of input / output waveforms in the mutual capacitance type touch sensor shown in FIG. 14 . In FIG. 14 , two cases of when a detection object is not detected (not touched) and when a detection object is detected (touched) are shown. Further, the waveforms of the wirings Y1 to Y6 show voltage values corresponding to the detected current values.

[0354] Pulse voltages are applied sequentially to wirings X1 to X6, and the waveforms of wirings Y1 to Y6 change according to these pulse voltages. When no object is near or in contact with the detector, the waveforms of wirings Y1 to Y6 change according to the voltage changes of wirings X1 to X6. On the other hand, when an object is near or in contact with the detector, the current value decreases, and therefore the waveform of the corresponding voltage value also changes. In this way, by detecting changes in mutual capacitance, the proximity or contact of the detector can be detected.

[0355] As a touch sensor FIG. 14 Although the structure of a passive touch sensor with capacitor 2603 placed only at the intersection of the wiring is shown, an active touch sensor with both transistors and capacitors can also be used. FIG. 15A An example of a sensor circuit included in an active touch sensor is shown.

[0356] FIG. 15B The sensor circuit shown includes capacitor 2603, transistor 2611, transistor 2612 and transistor 2613.

[0357] A gate signal G2 is supplied to transistor 2613, a voltage VRES is applied to one of the source and drain of transistor 2613, and the other of the source and drain of transistor 2613 is electrically connected to one electrode of capacitor 2603 and the gate of transistor 2611. One of the source and drain of transistor 2611 is electrically connected to one of the source and drain of transistor 2612, and a voltage VSS is applied to the other of the source and drain of transistor 2611. A gate signal G1 is supplied to transistor 2612, and the other of the source and drain of transistor 2612 is electrically connected to wiring ML. A voltage VSS is applied to the other electrode of capacitor 2603.

[0358] Next, regarding FIG. 16A The operation of the sensor circuit shown will be explained. First, a potential corresponding to voltage VRES is supplied to node n, which is connected to the gate of transistor 2611, by supplying a potential that turns transistor 2613 on as signal G2. Next, the potential of node n is maintained by supplying a potential that turns transistor 2613 off as signal G2. Then, due to the approach or contact of a detected object such as a finger, the mutual capacitance of capacitor 2603 changes, and the potential of node n changes from VRES accordingly.

[0359] During readout, a potential is applied as signal G1 to turn on transistor 2612. The current flowing through transistor 2611, i.e., the current flowing through wiring ML, varies according to the potential of node n. By detecting this current, the proximity or contact of the object being detected can be determined.

[0360] In the transistors 2611, 2612, and 2613, an oxide semiconductor layer is preferably used for a semiconductor layer in which a channel region is formed. In particular, by using such a transistor for the transistor 2613, the potential of the node n can be held for a long period, which can reduce the frequency of operation for supplying VRES to the node n again (refresh operation).

[0361] At least a part of this embodiment mode can be implemented in appropriate combination with other embodiment modes described in this specification.

[0362] Example 1

[0363] Synthesis Example 1

[0364] In this embodiment, a method for synthesizing a heterocyclic compound 2-[3-(benzo[l,2-b:4,5-b']biferan-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbfPDBq) (Structural Formula (101)), which is one embodiment of the present application, will be described. The structure of 2mBbfPDBq is shown below.

[0365] [Chemical Formula 41]

[0366]

[0367] Synthesis of 2mBbfPDBq

[0368] Step 1

[0369] Into a 200-mL three-necked flask, 8.9 g (30 mmol) of 1,4-dibromo-2,5-dimethoxybenzene, 10 g (72 mmol) of 2-fluorophenylboronic acid, 15 mL of toluene, 15 mL of diglyme, and 60 mL of an aqueous sodium carbonate solution (2.0 mol / L) were placed, and the mixture was degassed while the inside of the flask was subjected to reduced pressure with stirring.

[0370] After the degassing, the atmosphere in the flask was replaced with nitrogen, and then the mixture was heated to 80 °C. To the mixture, 0.69 g (0.60 mmol) of tetrakis(triphenylphosphine)palladium(0) was added, and the mixture was stirred at the same temperature for 2 hours. After the mixture was cooled to room temperature, the degassing was performed again under reduced pressure, the atmosphere in the flask was replaced with nitrogen, and the mixture was heated to 80 °C. After the heating, to the mixture, 0.69 g (0.60 mmol) of tetrakis(triphenylphosphine)palladium(0) was added, and the mixture was heated at the same temperature for 5 hours.

[0371] After heating, 2.0 g (14 mmol) of 2-fluorophenylboronic acid was added, and stirring was further performed for 3 hours at the same temperature. After heating, the mixture was cooled to room temperature, and then degassing was performed under reduced pressure, and the atmosphere in the flask was replaced with nitrogen. The mixture was heated to 80°C, and 0.64 g (0.55 mmol) of tetrakis(triphenylphosphine)palladium(0), 3.0 g (21 mmol) of 2-fluorophenylboronic acid were added thereto, and stirring was performed for 2 hours at the same temperature. After stirring, the mixture was cooled to room temperature, and was separated into an organic layer and an aqueous layer.

[0372] The resulting aqueous layer was extracted three times with toluene, and the extract and the organic layer were mixed, washed with saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to obtain the compound. The resulting mixture was recrystallized with toluene to obtain 2.5 g of the desired product. The compound obtained by concentrating the filtrate was purified by silica gel column chromatography (developing solvent: a mixed solvent of hexane: ethyl acetate = 30: 1) to obtain 0.3 g of the desired product. A total of 2.8 g of the desired product was obtained at a yield of 29%. The synthetic scheme of the above synthesis method is shown in the following formula (A-1).

[0373] [Chemical Formula 42]

[0374]

[0375] <Step 2>

[0376] A solution was obtained by pouring 2.8 g (8.7 mmol) of 1,4-bis(2-fluorophenyl)-2,5-dimethoxybenzene into a 300 mL three-necked flask, replacing the atmosphere in the flask with nitrogen, and then adding 20 mL of anhydrous dichloromethane. The solution was stirred in an ice bath, and a solution obtained by diluting 21 mL (21 mmol) of boron tribromide solution (1 mol / L dichloromethane solution) with 22 mL of anhydrous dichloromethane was dropped into the solution, and the solution obtained after the dropping was stirred at room temperature for about 15 hours.

[0377] After stirring, the resulting solution was cooled in an ice bath, and 10 mL of water and 5 mL of methanol were dropped. After the dropping, the precipitated solid was collected by suction filtration to obtain a white solid of the desired product. The resulting filtrate was separated into an organic layer and an aqueous layer, and the aqueous layer was extracted three times with dichloromethane. The extract and the organic layer were mixed, washed with a sodium bicarbonate aqueous solution and saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to obtain a white solid of the desired product. The synthetic scheme of the above synthesis method is shown in the following formula (A-2).

[0378] [Chemical Formula 43]

[0379]

[0380] <Step 3>

[0381] Into a 100 mL three-necked flask, 2.3 g (7.8 mmol) of 1,4-bis(2- fluorophenyl)-2,5-dihydroxybenzene obtained in Step 2, 4.2 g (30 mmol) of potassium carbonate, and 44 mL of N-methyl-2-pyrrolidone were placed, and the mixture was degassed while stirring under reduced pressure in the flask. After degassing, the atmosphere in the flask was replaced with nitrogen, and the mixture was stirred at 200°C for 4.5 hours. After the stirring, the mixture was cooled to room temperature, and toluene, water, and hydrochloric acid were added, and the mixture was stirred, and the mixture was separated into an organic layer and an aqueous layer.

[0382] The obtained aqueous layer was extracted with toluene three times. A solid was precipitated upon mixing the obtained extract and the organic layer, and the precipitated solid was collected by suction filtration. The obtained filtrate was washed with an aqueous sodium bicarbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The obtained mixture was gravity-filtered, the obtained filtrate was concentrated, and the obtained solid was recrystallized from toluene, to obtain 0.53 g of a solid of the object. The precipitated solid was recrystallized from toluene, to obtain 0.94 g of a white solid of the object. A total of 1.5 g (5.7 mmol) of a solid of the object was obtained at a yield of 73%. The synthetic scheme of the above synthesis is shown in the following formula (A-3).

[0383] [Chemical Formula 44]

[0384]

[0385] <Step 4>

[0386] Into a 100 mL three-necked flask, 1.4 g (5.5 mmol) of benzo[1,2-b:4,5-b']biferen-3-yl was placed, the atmosphere in the flask was replaced with nitrogen, and then 34 mL of anhydrous tetrahydrofuran was added, and the obtained solution was stirred at -78°C. 4.0 mL of n-butyllithium hexane solution (1.6 mol / L, 6.3 mmol) was dropped into the above solution, and after the dropping, the stirring was performed at the same temperature for 20 minutes, and the temperature of the obtained solution was increased to room temperature, and then the stirring was performed for 1 hour. After the prescribed time, the obtained solution was cooled to -78°C, and after the cooling, 1.5 mL (13 mmol) of trimethyl borate was dropped at the same temperature.

[0387] The temperature of the obtained solution was raised to room temperature, and then stirring was performed at room temperature for 15 hours. After the stirring, 50 mL of hydrochloric acid (1 mol / L) was added, and the mixture was stirred for 1 hour. After the stirring, the mixture was separated into an organic layer and an aqueous layer, and the obtained aqueous layer was extracted twice with ethyl acetate. The obtained extract and the organic layer were combined, washed with an aqueous sodium bicarbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The obtained mixture was gravity filtered, and the obtained filtrate was concentrated to obtain the solid of the object.

[0388] The obtained solid was washed with chloroform and suction filtered to obtain 0.53 g of the solid of the object. The compound obtained by concentrating the obtained filtrate was recrystallized from toluene / hexane to obtain 0.60 g of the solid of the object. A total of 1.1 g (3.7 mmol) of the solid of the object was obtained in a yield of 67%. The synthetic scheme of the above-described synthesis method is shown in the following formula (A-4).

[0389] [Chemical Formula 45]

[0390]

[0391] <Step 5>

[0392] Into a 100 mL three-necked flask, 1.2 g (3.1 mmol) of 2-(3-bromophenyl)dibenzo[f,h]quinoxaline, 1.1 g (3.6 mmol) of benzo[1,2-b:4,5-b']bisthiofuran-6-boronic acid, 50 mg (0.16 mmol) of tri(2-methylphenyl)phosphine, 15 mL of toluene, 2 mL of ethanol, and 5 mL of an aqueous potassium carbonate solution (2.0 mol / L) were poured, and the mixture was degassed while the inside of the flask was reduced in pressure with stirring.

[0393] After the degassing, the atmosphere inside the flask was replaced with nitrogen, and then the mixture was heated to 80°C. To the mixture, 10 mg (45 μmol) of palladium (II) acetate was added, and stirring was performed for 7 hours. After the stirring, the mixture was cooled to room temperature, and the precipitated solid was collected by suction filtration. The obtained solid was washed with water and ethanol to obtain the solid of the object. The obtained solid was dissolved in toluene by heating, and the obtained solid was filtered using diatomaceous earth and alumina. The solid obtained by concentrating the obtained filtrate was recrystallized from toluene to obtain 1.0 g (1.8 mmol) of the solid of the object in a yield of 58%.

[0394] The obtained 1.0 g solid was purified by sublimation using a gradient sublimation method. In the sublimation purification, the solid was heated at 335 °C for 16.5 h under conditions of argon gas flowing through it at a pressure of 2.6 Pa and a flow rate of 5 mL / min. After sublimation purification, 0.61 g of the target substance was obtained as a pale yellow solid with a recovery rate of 59%. The synthetic scheme of the above method is shown in the following formula (A-5).

[0395] [Chemical Formula 46]

[0396]

[0397] The following shows the nuclear magnetic resonance spectroscopy of the pale yellow solid obtained by the above synthesis method. 1 The analysis results of H-NMR. In addition, FIG. 16B and FIG. 17A Show 1 H-NMR spectrum. Based on this result, it can be seen that in this synthetic example 1, a heterocyclic compound 2mBbfPDBq of one aspect of the present invention, represented by the above structural formula (101), was obtained.

[0398] 1 ¹H-NMR (tetrachloroethane-d², 500MHz): δ = 7.25 (t, J = 7.5Hz, 1H), 7.48 (t, J = 7.5Hz, 1H), 7.52–7.59 (m, 2H), 7.67 (d, J = 8.0Hz, 1H), 7.72 (d, J = 8.0Hz, 1H), 7.77 (t, J = 7.0Hz, 2H), 7.82–7.89 (m, 3H), 7.98 (t, J = 7.0Hz, 2H). 5Hz,1H), 8.09(d,J=7.5Hz,1H), 8.16(d,J=7.5Hz,1H), 8.22(d,J=1.0Hz,1H), 8.63(d,J=7.5Hz,1 H), 8.71 (d, J = 7.5Hz, 2H), 8.88 (s, 1H), 9.34 (d, J = 8.0Hz, 1H), 9.43 (d, J = 8.0Hz, 1H), 9.57 (s, 1H).

[0399] Next, the UV-Vis absorption spectra (hereinafter simply referred to as "absorption spectra") and emission spectra of the 2 mBbfPDBq toluene solution and the solid film were measured. The solid film was fabricated on a quartz substrate by vacuum evaporation. The absorption spectrum was measured using a UV-Vis spectrophotometer (V550 model, manufactured by Nippon Spectrophotometer Co., Ltd.). The emission spectrum was measured using a fluorescence spectrophotometer (FS920 model, manufactured by Hamamatsu Photonics Co., Ltd., Japan). FIG. 17B The absorption and emission spectra of the obtained toluene solution are shown. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity.FIG. 18A The measurement results of the absorption spectrum and the emission spectrum of the solid thin film are shown. The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

[0400] According to the results of FIG. 18B , in the case of a toluene solution of 2 mBbf PDBq, absorption peaks were observed near 282 nm and 333 nm, and emission wavelength peaks were observed near 392 nm and 404 nm. According to the results of FIG. 19A , in the case of a solid thin film of 2 mBbf PDBq, absorption peaks were observed near 263 nm and 337 nm, and emission wavelength peaks were observed near 429 nm.

[0401] Example 2

[0402] Synthesis Example 2

[0403] In this example, a method for synthesizing the heterocyclic compound 2-[3-(benzo[l,2-b:5,4-b']bifuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf (II) PDBq) (structural formula (107)), which is one embodiment of the present application, is described. The structure of 2mBbf (II) PDBq is shown below.

[0404] [Chemical Formula 47]

[0405]

[0406] <2mBbf (II) PDBq Synthesis>

[0407] <Step 1>

[0408] Into a 200-mL three-necked flask, 5.0 g (36 mmol) of 1,3-dimethoxybenzene was placed, and the mixture was degassed while the inside of the flask was depressurized with stirring. After the degassing, the atmosphere in the flask was replaced with nitrogen, 80 mL of dehydrated dichloromethane was added, and the mixture was stirred. While the resulting solution was cooled in an ice bath, a solution in which 12 g (75 mmol) of bromine was dissolved in 14 mL of dehydrated dichloromethane was dropped into the flask.

[0409] After the dropping, the resulting solution was stirred at room temperature for 15 hours. After the stirring, while the resulting solution was cooled in an ice bath, an aqueous sodium bicarbonate solution and a saturated aqueous sodium thiosulfate solution were added until the pH was 8. The resulting mixture was separated into an organic layer and an aqueous layer, and the resulting aqueous layer was extracted with dichloromethane three times. The resulting extract solution and the organic layer were mixed, and washed with saturated brine. The resulting organic layer was dried with anhydrous magnesium sulfate, and the mixture was subjected to gravity filtration to obtain a filtrate.

[0410] After adding hexane to the obtained solid of the filtrate subjected to concentration and irradiating ultrasound, the mixture was subjected to suction filtration to obtain a solid. The obtained solid was recrystallized using hexane / ethyl acetate to obtain 7.2 g (24 mmol) of the solid of the object substance at a yield of 67%. The synthetic scheme of the above-described synthesis method is shown in the following Formula (B-1).

[0411] [Chemical Formula 48]

[0412]

[0413] <Step 2>

[0414] Into a 200 mL three-necked flask, 7.1 g (24 mmol) of 1,5-dibromo-2,4-dimethoxybenzene, 2.8 g (20 mmol) of 2-fluorophenylboronic acid, 12 mL of toluene, 12 mL of diethyleneglycol dimethyl ether, 50 mL of an aqueous sodium carbonate solution (2 mol / L) were poured, and stirring was performed while reducing the pressure inside the flask to degas the mixture. After degassing, the atmosphere inside the flask was replaced with nitrogen, and then the mixture was heated to 80°C.

[0415] To the mixture, 0.55 g (0.48 mmol) of tetrakis(triphenylphosphine)palladium(0) was added, and stirring was performed at the same temperature for 3 hours. After cooling the mixture to room temperature, 4.5 g (32 mmol) of 2-fluorophenylboronic acid, 0.12 g (0.29 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl were added, and degassing was performed under reduced pressure, the atmosphere inside the flask was again replaced with nitrogen, and then the mixture was heated to 80°C. Then, 30 mg (0.13 mmol) of palladium(II) acetate was added, and stirring was performed at the same temperature for 4 hours.

[0416] After stirring, the mixture was cooled to room temperature, and separated into an organic layer and an aqueous layer. The obtained aqueous layer was extracted three times using toluene, the extract and the organic layer were mixed, washed using saturated brine, and dried using anhydrous magnesium sulfate. The obtained mixture was subjected to gravity filtration, and the obtained filtrate was concentrated to obtain a brown oil. The oil was purified using silica gel column chromatography (as a developing solvent, gradually changed from hexane to chloroform using a gradient method) to obtain 7.2 g (22 mmol) of the object substance as a yellowish oil at a yield of 92%. The synthetic scheme of the above-described synthesis method is shown in the following Formula (B-2).

[0417] [Chemical Formula 49]

[0418]

[0419] <Step 3>

[0420] Into a 500 mL three-necked flask, 7.2 g (22 mmol) of 1,5-bis(2-fluorophenyl)-2,4-dimethoxybenzene was placed, the atmosphere in the flask was replaced with nitrogen, and then 60 mL of dehydrated dichloromethane was added to obtain a solution. The obtained solution was placed in an ice bath and stirred, and a solution prepared by diluting 53 mL (53 mmol) of boron tribromide solution (1 mol / L dichloromethane solution) with 50 mL of dehydrated dichloromethane was added dropwise to the above solution. The solution obtained after the dropwise addition at room temperature was stirred for 15 hours. After the stirring, the obtained solution was again cooled in an ice bath, 40 mL of water and 40 mL of methanol were added dropwise, and the obtained mixture was separated into an organic layer and an aqueous layer. The obtained aqueous layer was extracted three times with dichloromethane, and the obtained extract and the organic layer were combined, washed with a sodium bicarbonate aqueous solution and saturated brine, and dried over anhydrous magnesium sulfate. The obtained mixture was gravity filtered, and the obtained filtrate was concentrated to obtain 7 g of the desired product as a yellowish oil. The synthetic scheme of the above synthesis method is shown in the following formula (B-3).

[0421] [Chemical Formula 50]

[0422]

[0423] <Step 4>

[0424] Into a 300 mL three-necked flask, 7 g or so (22 mmol or so) of 1,5-bis(2-fluorophenyl)-2,4-dihydroxybenzene obtained in Step 3, 13 g (96 mmol) of potassium carbonate, and 140 mL of N-methyl-2-pyrrolidone were placed, and the mixture was degassed while stirring in the flask under reduced pressure. After the degassing, the atmosphere in the flask was replaced with nitrogen, and then the mixture was stirred at 200°C for 7 hours.

[0425] After the stirring, the mixture was cooled to room temperature, and then toluene, water, and hydrochloric acid were added and stirred. The obtained mixture was separated into an organic layer and an aqueous layer, and the aqueous layer was extracted three times with toluene. The obtained extract and the organic layer were combined, washed with a sodium bicarbonate aqueous solution and saturated brine, and dried over anhydrous magnesium sulfate. The mixture was gravity filtered, and the obtained filtrate was concentrated to obtain a yellow oil. The obtained oil was recrystallized with toluene / hexane to obtain the desired product as a white powdery solid.

[0426] The obtained solid was recrystallized using toluene / hexane to obtain a solid of the object. The oil obtained by concentrating the recrystallized filtrate was purified using silica gel column chromatography (developing solvent: hexane) and recrystallized using hexane to obtain a white powdery solid of the object. A total of 2.2 g (8.5 mmol) of a white powdery solid was obtained in a yield of 39% through the two stages of Step 3 and Step 4. The synthetic scheme of the above synthesis method is shown in the following Formula (B-4).

[0427] [Chemical Formula 51]

[0428]

[0429] <Step 5>

[0430] The 2.2 g (8.5 mmol) of benzo[1,2-b:4,5-b']dibenzofuran was poured into a 200 mL three-necked flask, and the inside of the flask was subjected to reduced pressure while being stirred to degas the compound. After degassing, the atmosphere in the flask was replaced with nitrogen, 40 mL of dehydrated tetrahydrofuran was added, and the obtained solution was stirred at -78°C.

[0431] After stirring, 5.6 mL of n-butyllithium hexane solution (1.60 mol / L, 9.0 mmol) was dropped into the above solution at room temperature, and after dropping, the temperature of the obtained solution was raised to room temperature, and then stirred for 30 minutes. After stirring, the obtained solution was cooled to -78°C, and 2.20 g (8.7 mmol) of iodine was dissolved in 10 mL of dehydrated tetrahydrofuran to prepare a solution at the same temperature. After dropping, the temperature of the obtained solution was raised to room temperature, and stirred at the same temperature for about 15 hours.

[0432] After stirring, water was added to the obtained solution, the obtained mixture was separated into an organic layer and an aqueous layer, the obtained aqueous layer was extracted three times with toluene, the obtained extract and the organic layer were mixed, washed with a sodium bicarbonate aqueous solution, a sodium thiosulfate aqueous solution, and saturated brine, and dried with anhydrous magnesium sulfate. The obtained mixture was subjected to gravity filtration, the obtained filtrate was concentrated, and the solid obtained by concentrating the filtrate was recrystallized using toluene / hexane to obtain 2.5 g (6.5 mmol) of a light brown solid of the object in a yield of 76%. The synthetic scheme of the above synthesis method is shown in the following Formula (B-5).

[0433] [Chemical Formula 52]

[0434]

[0435] <Step 6>

[0436] A 200 mL three-necked flask was charged with 1.5 g (3.8 mmol) of 6-iodo- benzo[l,2-b:5,4-b']biferen-3-yl, 1.8 g (4.2 mmol) of 2-[3-(2-dibenzo[f,h] quinoxaline)phenyl]-4,4,5,5-tetramethyl-l,3,2-dioxaborolane, 70 mg (0.23 mmol) of tri(2-methylphenyl)phosphine, 20 mL of toluene, 2 mL of ethanol, and 6 mL of an aqueous potassium carbonate solution (2.0 mol / L), and the mixture was degassed while stirring under reduced pressure inside the flask.

[0437] After degassing, the atmosphere inside the flask was replaced with nitrogen, and the mixture was heated to 80°C. After heating, 10 mg (45 μmol) of palladium(II) acetate was added to the mixture, and the mixture was stirred for 2.5 hours at the same temperature. After stirring, the mixture was cooled to room temperature, 10 mg (45 μmol) of palladium(II) acetate was added again, and the mixture was stirred for 8 hours. After cooling the mixture to room temperature, the mixture was concentrated, 20 mL of ethylene glycol dimethyl ether and 6 mL of an aqueous sodium carbonate solution (2.0 mol / L) were added, and the mixture was degassed while stirring under reduced pressure inside the flask.

[0438] After degassing, the atmosphere inside the flask was replaced with nitrogen, and the mixture was heated to 80°C. After heating, 10 mg (45 μmol) of palladium(II) acetate was added to the mixture, and the mixture was stirred for 2.5 hours at the same temperature. After stirring, the mixture was cooled to room temperature, 10 mg (45 μmol) of palladium(II) acetate was added again, and the mixture was stirred for 8 hours. After cooling the mixture to room temperature, the mixture was concentrated, 20 mL of ethylene glycol dimethyl ether and 6 mL of an aqueous sodium carbonate solution (2.0 mol / L) were added, and the mixture was degassed while stirring under reduced pressure inside the flask.

[0439] The obtained solid was purified by sublimation using a gradient sublimation method. In the sublimation purification, the solid was heated at 310°C for 15.5 hours under a pressure of 2.5 Pa and with argon flowing at a flow rate of 5 mL / min. After the sublimation purification, 0.90 g of the pale yellow solid of the object was obtained in a recovery rate of 75%. The synthetic scheme of the above synthesis method is shown in the following formula (B-6).

[0440] [Chemical Formula 53]

[0441]

[0442] The nuclear magnetic resonance spectroscopy of the pale yellow solid obtained using the above synthesis method is shown below.1 H-NMR) analysis results. In addition, FIG. 19B and FIG. 20A shows 1 H-NMR spectrum. From this result, in the present synthetic example 2, the heterocyclic compound 2mBbf (II) PDBq of one embodiment of the present application represented by the above structural formula (107) was obtained.

[0443] 1 H-NMR (tetrachloroethane-d2, 500 MHz): δ = 7.49 (t, J = 8.0 Hz, 2H), 7.56 (t, J = 8.0 Hz, 2H), 7.74 (d, J = 8.0 Hz, 2H), 7.81-7.89 (m, 4H), 7.93 (t, J = 8.0 Hz, 1H), 8.18 (d, J = 7.5 Hz, 2H) 8.43 (d, J = 6.5 Hz, 1H), 8.53 (d, J = 8.0 Hz, 1H), 8.56 (s, 1H), 8.71 (d, J = 8.0 Hz, 2H), 9.27 (s, 1H), 9.34 (d, J = 7.5 Hz, 1H), 9.56 (d, J = 8.0 Hz, 1H), 9.60 (s, 1H).

[0444] Next, the ultraviolet-visible absorption spectrum (hereinafter, simply referred to as "absorption spectrum") and the emission spectrum of the toluene solution and the solid thin film of 2mBbf (II) PDBq were measured. The solid thin film was produced on a quartz substrate by a vacuum deposition method. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (manufactured by Japan Spectroscopic Co., Ltd., V550 type). The emission spectrum was measured using a fluorescence spectrophotometer (manufactured by Hamamatsu Photonics K.K., FS920). FIG. 20B The measurement results of the absorption spectrum and the emission spectrum of the obtained toluene solution are shown. The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity. FIG. 20A The measurement results of the absorption spectrum and the emission spectrum of the solid thin film are shown. The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

[0445] From the results of FIG. 20B , in the case of the toluene solution of 2mBbf (II) PDBq, absorption peaks were observed around 281 nm and 288 nm, and the peak of the emission wavelength was observed around 393 nm and 404 nm. From the results of FIG. 21A , in the case of the solid thin film of 2mBbf (II) PDBq, absorption peaks were observed around 265 nm and 384 nm, and the peak of the emission wavelength was observed around 430 nm.

[0446] Example 3

[0447] Synthetic Example 3

[0448] In the present embodiment, a method for synthesizing the heterocyclic compound 2-[3-(benzo[l,2-b:5,6-b']bifuran-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)PDBq) (Formula (149)) of one embodiment of the present application will be described. The structure of 2mBbf(III)PDBq is shown below.

[0449] [Chemical Formula 54]

[0450]

[0451] <2mBbf(III)PDBq Synthesis>

[0452] <Step 1>

[0453] A 500-mL three-necked flask was charged with 10 g (46 mmol) of 2-bromo-l,3-dimethoxybenzene, 7.2 g (51 mmol) of 2-fluorophenylboronic acid, 66 mL of toluene, 66 mL of diglyme, 76 mL of an aqueous sodium carbonate solution (2.0 mol / L), and the inside of the flask was degassed while being stirred under reduced pressure. After degassing, the atmosphere in the flask was replaced with nitrogen, and then the mixture was heated to 80°C. To the mixture, 1.1 g (0.95 mmol) of tetrakis(triphenylphosphine)palladium(0) was added, and the mixture was stirred for 5 hours at the same temperature.

[0454] After the stirring, the resulting mixture was cooled to room temperature, and then 3.2 g (23 mmol) of 2-fluorophenylboronic acid, 1.0 g (0.87 mmol) of tetrakis(triphenylphosphine)palladium(0) were added, the inside of the flask was degassed while being stirred under reduced pressure, the atmosphere in the flask was replaced with nitrogen, and then the mixture was stirred at 80°C for 8 hours. After the stirring, the resulting mixture was cooled to room temperature, and then 5.2 g (37 mmol) of 2-fluorophenylboronic acid, 0.19 g (0.46 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, and 50 mg (0.22 mmol) of palladium(II) acetate were added, the mixture was degassed while being stirred under reduced pressure. After the atmosphere in the flask was replaced with nitrogen, the mixture was stirred at 80°C for 4 hours.

[0455] After stirring, the mixture was cooled to room temperature and separated into an organic layer and an aqueous layer. The resulting aqueous layer was extracted three times with toluene, the extract and the organic layer were combined, washed with saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity filtered, and the resulting filtrate was concentrated to give a dark brown oil. The resulting oil was purified by silica gel column chromatography (as a developing solvent, a gradient from hexane to chloroform was used) and recrystallized from toluene / hexane to give 8.4 g (36 mmol) of the desired product as a solid in a yield of 78%. The synthetic scheme of the above synthesis is shown in the following Formula (C-l).

[0456] [Chemical Formula 55]

[0457]

[0458] <Step 2>

[0459] Into a 300 mL conical flask were placed 8.4 g (36 mmol) of 2'-fluoro-l,3-dimethoxy-2,l'-biphenyl and 130 mL of acetonitrile, and to the resulting solution was added 6.4 g (36 mmol) of N-bromosuccinimide, and the resulting solution was stirred at room temperature for 23.5 hours. After stirring, water and dichloromethane were added to the resulting solution, and the mixture was separated into an organic layer and an aqueous layer.

[0460] The aqueous layer was extracted three times with dichloromethane, the resulting extract and the organic layer were combined, washed with saturated aqueous sodium thiosulfate and saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity filtered, and the resulting filtrate was concentrated to give 11 g (35 mmol) of the desired product as a yellow oil in a yield of 97%. The synthetic scheme of the above synthesis is shown in the following Formula (C-2).

[0461] [Chemical Formula 56]

[0462]

[0463] <Step 3>

[0464] Into a 300 mL three-necked flask, 11 g (35 mmol) of 4-bromo-2'-fluoro-1,3-dimethoxy-2,1'-biphenyl was charged, the atmosphere in the flask was replaced with nitrogen, and then 6.51 g (37 mmol) of 3-chloro-2-fluoro-benzoic acid, 55 mL of an aqueous sodium carbonate solution (2.0 mol / L), 50 mL of toluene, 50 mL of ethylene glycol dimethyl ether, and 0.16 g (0.39 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl were added. While the inside of the flask was subjected to reduced pressure, stirring was performed to degas the mixture. After degassing, the atmosphere in the flask was replaced with nitrogen, and then the mixture was heated to 80°C. Thereafter, 40 mg (0.18 mmol) of palladium (II) acetate was added, and stirring was performed at the same temperature for 2 hours.

[0465] After stirring, the resulting mixture was cooled to room temperature, and then 3.4 g (19 mmol) of 3-chloro-2-fluoro-benzoic acid was added, and the mixture was heated to 80°C. To the mixture, 40 mg (0.18 mmol) of palladium (II) acetate was added, and stirring was performed at the same temperature for 3 hours. After stirring, 0.90 g (5.2 mmol) of 3-chloro-2-fluoro-benzoic acid and 40 mg (0.18 mmol) of palladium (II) acetate were added, and the mixture was heated to 80°C, and the mixture was stirred for 7 hours. After stirring, the resulting mixture was cooled to room temperature, and then the mixture was separated into an organic layer and an aqueous layer. The resulting aqueous layer was extracted with toluene three times, and the extract and the organic layer were combined, washed with saturated brine, and dried with anhydrous magnesium sulfate. The resulting mixture was subjected to gravity filtration, and the resulting filtrate was concentrated to obtain an oil.

[0466] The resulting oil was purified by silica gel column chromatography (developing solvent: a mixed solvent of hexane: ethyl acetate = 10: 1), and recrystallized from toluene / hexane to obtain a solid of the desired product. The solid obtained by concentrating the mother liquid of recrystallization was purified by high performance liquid chromatography (developing solution: chloroform), and recrystallized from toluene / hexane to obtain a solid of the desired product. A total of 9.9 g (28 mmol) of a solid of the desired product was obtained at a yield of 80%. The synthetic scheme of the above-described synthesis method is shown in the following formula (C-3).

[0467] [Chemical Formula 57]

[0468]

[0469] <Step 4>

[0470] A 500 mL three-necked flask was charged with 9.8 g (27 mmol) of 4-(3-chloro-2- fluorophenyl)-2-(2-fluorophenyl)-l,3-dimethoxybenzene, and the atmosphere in the flask was replaced with nitrogen. Then, 150 mL of anhydrous dichloromethane was added. The resulting solution was placed in an ice bath and stirred, and a solution prepared by diluting 70 mL (70 mmol) of boron tribromide (1 mol / L dichloromethane solution) with 90 mL of anhydrous dichloromethane was added dropwise to the resulting solution. The solution obtained after the dropwise addition was stirred at room temperature for 15 hours. After the stirring, the resulting solution was cooled in an ice bath, 20 mL of methanol was added dropwise, and then 40 mL of water was added dropwise. The resulting mixture was separated into an organic layer and an aqueous layer, the resulting aqueous layer was extracted with dichloromethane three times, the extract and the organic layer were combined, washed with an aqueous sodium bicarbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to obtain a brown oil. The resulting oil was purified by silica gel column chromatography (developing solvent: a mixed solvent of hexane: ethyl acetate = 8: 1), and recrystallized from toluene / hexane to obtain 8.7 g (26 mmol) of the desired product as a white solid at a yield of 96%. The synthetic scheme of the above synthesis method is shown in the following formula (C-4).

[0471] [Chemical Formula 58]

[0472]

[0473] <Step 5>

[0474] A 500 mL three-necked flask was charged with 9.8 g (27 mmol) of 4-(3-chloro-2- fluorophenyl)-2-(2-fluorophenyl)-l,3-dimethoxybenzene, and the atmosphere in the flask was replaced with nitrogen. Then, 150 mL of anhydrous dichloromethane was added. The resulting solution was placed in an ice bath and stirred, and a solution prepared by diluting 70 mL (70 mmol) of boron tribromide (1 mol / L dichloromethane solution) with 90 mL of anhydrous dichloromethane was added dropwise to the resulting solution. The solution obtained after the dropwise addition was stirred at room temperature for 15 hours. After the stirring, the resulting solution was cooled in an ice bath, 20 mL of methanol was added dropwise, and then 40 mL of water was added dropwise. The resulting mixture was separated into an organic layer and an aqueous layer, the resulting aqueous layer was extracted with dichloromethane three times, the extract and the organic layer were combined, washed with an aqueous sodium bicarbonate solution and saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to obtain a brown oil. The resulting oil was purified by silica gel column chromatography (developing solvent: a mixed solvent of hexane: ethyl acetate = 8: 1), and recrystallized from toluene / hexane to obtain 8.7 g (26 mmol) of the desired product as a white solid at a yield of 96%. The synthetic scheme of the above synthesis method is shown in the following formula (C-4).

[0475] The resulting aqueous layer was extracted three times with toluene. The resulting extract and organic layer were combined, washed with aqueous sodium bicarbonate and saturated brine, and dried over anhydrous magnesium sulfate. The resulting mixture was gravity filtered, and the resulting filtrate was concentrated to give a brown solid. The resulting solid was recrystallized from toluene / hexane to give a total of 3.4 g (12 mmol) of first crystalline product and 1.6 g (5.4 mmol) of second crystalline product in 67% yield. The above synthesis is shown in the following scheme of the synthesis of Formula (C-5).

[0476] [Chemical Formula 59]

[0477]

[0478] <Step 6>

[0479] To a 100 mL three-necked flask were placed 1.5 g (5.2 mmol) of 4-chlorobenzo[l,2-b;5,6-b']biferan, 2.5 g (5.7 mmol) of 2-[3-(2-dibenzo[f,h]quinoxalinyl)phenyl]-4,4,5,5-tetramethyl-l,3,2-dioxaborolane, 80 mg (0.22 mmol) of bis(l-adamantyl)(n-butyl)phosphine, 1.5 mL (16 mmol) of t-butanol, 3.6 g (17 mmol) of potassium phosphate (III), and 26 mL of diglyme, and the mixture was degassed while stirring under reduced pressure inside the flask. After degassing, the atmosphere inside the flask was replaced with nitrogen, and the mixture was heated to 80°C.

[0480] To the mixture was added 10 mg (45 μmol) of palladium (II) acetate, and the mixture was stirred at the same temperature for 4 hours. After stirring, the mixture was cooled to room temperature, 10 mg (45 μmol) of palladium (II) acetate was added, and the mixture was stirred at 100°C for 7 hours. Then, after cooling the mixture to room temperature, 20 mg (89 μmol) of palladium (II) acetate was added, and the mixture was stirred at 120°C for 4.5 hours. After stirring, the mixture was cooled to room temperature, and the precipitate was collected by suction filtration.

[0481] The resulting solid was washed with water and ethanol. The resulting solid was dissolved in toluene by heating, and the resulting solution was filtered using celite and alumina. The solid obtained by concentrating the resulting filtrate was recrystallized using toluene, and 1.4 g (2.4 mmol) of the solid of the desired product was obtained in 46% yield.

[0482] The obtained solid was purified by sublimation using a gradient sublimation method. In the sublimation purification, the solid was heated at 305°C for 20 hours under argon gas flow at a pressure of 2.8 Pa and a flow rate of 10 mL / min. After sublimation purification, 1.1 g of the target substance was obtained as a pale yellow solid with a recovery rate of 77%. The synthetic scheme of the above method is shown in the following formula (C-6).

[0483] [Chemical Formula 60]

[0484]

[0485] The following shows the nuclear magnetic resonance spectroscopy of the pale yellow solid obtained by the above synthesis method. 1 The analysis results of H-NMR. In addition, FIG. 21B and FIG. 22A Show 1 H-NMR spectrum. Based on this result, it can be seen that in this synthetic example 3, a heterocyclic compound 2mBbf(III)PDBq of one aspect of the present invention, represented by the above structural formula (149), was obtained.

[0486] 1 ¹H-NMR (tetrachloroethane-d², 500MHz): δ = 7.29 (t, J = 7.5Hz, 1H), 7.50 (t, J = 7.5Hz, 1H), 7.62–7.73 (m, 4H), 7.80–7.89 (m, 4H), 7.92 (t, J = 7.5Hz, 1H), 8.12 (d, J = 7.5Hz, 1H), 8. 15(d,J=8.5Hz,1H), 8.29(d,J=7.5Hz,2H), 8.54(d,J=8.0Hz,1H), 8.70(t,J=8.0 Hz, 2H), 9.15 (s, 1H), 9.36 (d, J = 7.5Hz, 1H), 9.48 (d, J = 7.5Hz, 1H), 9.65 (s, 1H).

[0487] Next, the UV-Vis absorption spectra (hereinafter simply referred to as "absorption spectra") and emission spectra of the 2mBbf(III)PDBq toluene solution and the solid film were measured. The solid film was fabricated on a quartz substrate by vacuum evaporation. The absorption spectrum was measured using a UV-Vis spectrophotometer (V550 model, manufactured by Nippon Spectrophotometer Co., Ltd.). The emission spectrum was measured using a fluorescence spectrophotometer (FS920 model, manufactured by Hamamatsu Photonics Co., Ltd., Japan). FIG. 22B The absorption and emission spectra of the obtained toluene solution are shown. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity. FIG. 22A The measurement results of the absorption and emission spectra of the solid thin film are shown. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity.

[0488] According to the results of FIG. 22B , in the case of a toluene solution of 2 mBbf(III)PDBq, absorption peaks were observed near 281 nm and 376 nm, and emission wavelength peaks were observed near 394 nm and 407 nm. According to the results of FIG. 23 , in the case of a solid thin film of 2 mBbf(III)PDBq, absorption peaks were observed near 266 nm and 384 nm, and emission wavelength peaks were observed near 429 nm.

[0489] Example 4

[0490] Synthesis Example 4

[0491] In this example, a method for synthesizing a heterocyclic compound 2-[3'-(benzo[l,2-b:5,6-b']biferan-4-yl)-l,l'-biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)BPDBq) of one embodiment of the present application is described. The structure of 2mBbf(III)BPDBq is shown below.

[0492] [Chemical Formula 61]

[0493]

[0494] <2mBbf(III)BPDBq Synthesis>

[0495] <Step 1>

[0496] A 200-mL three-necked flask was charged with 1.5 g (2.8 mmol) of 4-chlorobenzo[l,2-b;5,6-b']biferan, 1.4 g (3.2 mmol) of 2-[3'-(2-dibenzo[f,h]quinoxaline)-l,l'-biphenyl-3-yl]-4,4,5,5-tetramethyl-l,3,2-dioxaborolane, 60 mg (0.17 mmol) of bis(l-adamantyl)(n-butyl)phosphine, 1 mL of t-butanol, 1.7 g (8.2 mmol) of potassium phosphate (III), and 15 mL of diglyme, and the mixture was degassed while being stirred under reduced pressure in the interior of the flask.

[0497] After degassing, the atmosphere in the flask was replaced with nitrogen, and then the mixture was heated to 80°C. After heating, 10 mg (45 μmol) of palladium (II) acetate was added to the mixture, and the mixture was stirred for 6 hours at the same temperature. After stirring, the resulting mixture was cooled to room temperature, 10 mg (45 μmol) of palladium (II) acetate was added, and the mixture was stirred for 4.5 hours at 120°C and then stirred for 3 hours at 140°C. After stirring, the mixture was cooled to room temperature, and then the precipitated solid was collected by suction filtration. The resulting solid was washed with water and ethanol, and 1.6 g (2.4 mmol) of the object as a light brown solid was obtained at a yield of 86%.

[0498] The resulting 1.49 g of solid was purified by sublimation using a gradient sublimation method. In the sublimation purification, the solid was heated at 350°C for 15 hours under a pressure of 5.1 Pa and with argon flowing at a flow rate of 15 mL / min. After the sublimation purification, 1.1 g of the object as a light yellow solid was obtained at a recovery rate of 76%. The synthetic scheme of the above-described synthesis method is shown in the following formula (D-1).

[0499] [Chemical Formula 62]

[0500]

[0501] The analysis results of the nuclear magnetic resonance spectroscopy (H-NMR) of the light yellow solid obtained using the above-described synthesis method are shown below. 1 H-NMR) of the light yellow solid obtained using the above-described synthesis method are shown below. FIG. 24 and FIG. 25 showed 1 H-NMR spectrum. According to the results, in this synthesis example 4, the heterocyclic compound 2mBbf (III) BPDBq of one embodiment of the present application represented by the above structural formula (150) was obtained.

[0502] 1H-NMR (tetrachloroethane-d2, 500 MHz): δ = 7.20 (t, J = 7.5 Hz, 1H), 7.31 (t, J = 7.5 Hz, 1H), 7.50 (d, J = 7.5 Hz, 1H), 7.58 (t, J = 7.5 Hz, 2H), 7.65 (d, J = 7.5 Hz, 1H), 7.75-7.84 (m, 6H), 7.93 (d, J = 7.5 Hz, 1H), 8.03 (d, J = 7.5 Hz, 1H), 8.07 (d, J = 7.5 Hz, 1H), 8.12 (t, J = 7.5 Hz, 2H), 8.20 (d, J = 7.5 Hz, 1H), 8.38 (d, J = 7.5 Hz, 1H), 8.62-8.66 (m, 3H), 8.82 (s, 1H), 9.27 (d, J = 7.5 Hz, 1H), 9.32 (d, J = 7.5 Hz, 1H), 9.49 (s, 1H).

[0503] Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and the emission spectrum of a toluene solution and a solid thin film of 2mBbf (III) BPDBq were measured. The solid thin film was produced on a quartz substrate by a vacuum deposition method. The absorption spectrum was measured using an ultraviolet-visible spectrophotometer (manufactured by Japan Spectroscopic Co., Ltd., Model V550). The emission spectrum was measured using a fluorescence spectrophotometer (manufactured by Hamamatsu Photonics K.K., FS920). FIG. 26 The measurement results of the absorption spectrum and the emission spectrum of the obtained toluene solution are shown. The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity. FIG. 27 The measurement results of the absorption spectrum and the emission spectrum of the solid thin film are shown. The horizontal axis represents the wavelength, and the vertical axis represents the absorption intensity.

[0504] According to the results of FIG. 28 , in the case of the toluene solution of 2mBbf (III) BPDBq, absorption peaks were observed near 264 nm and 385 nm, and peaks of the emission wavelength were observed near 391 nm and 407 nm. According to the results of FIG. 28 , in the case of the solid thin film of 2mBbf (III) BPDBq, absorption peaks were observed near 264 nm and 385 nm, and a peak of the emission wavelength was observed near 425 nm.

[0505] Example 5

[0506] In this embodiment, a light-emitting element 1 using a heterocyclic compound 2mBbfPDBq (structural formula (101)) of one embodiment of the present application, a light-emitting element 2 using a heterocyclic compound 2mBbf(ll)PDBq (structural formula (107)) of one embodiment of the present application, a light-emitting element 3 using a heterocyclic compound 2mBbf(lll)PDBq (structural formula (149)) of one embodiment of the present application, and a light-emitting element 4 using a heterocyclic compound 2mBbf(lll)BPDBq (structural formula (150)) of one embodiment of the present application are manufactured. Further, for comparison, a comparative light-emitting element 5 using 2mDBTBPDBq-II having a dibenzothiophene structure is manufactured. The materials used in this embodiment are listed below. FIG. 29 Manufacture of the light-emitting elements 1 to 4 and the comparative light-emitting element 5 is described. Hereinafter, chemical formulas of the materials used in this embodiment are shown.

[0507] [Chemical Formula 63]

[0508]

[0509] [Chemical Formula 64]

[0510]

[0511] Manufacture of the light-emitting elements 1 to 4 and the comparative light-emitting element 5

[0512] First, a film of indium tin oxide (ITO) containing silicon oxide was formed over a glass substrate 900 by a sputtering method, whereby a first electrode 901 used as an anode was formed. The thickness was set to 110 nm and the electrode area was set to 2 mm x 2 mm.

[0513] Next, as a pretreatment for forming the light-emitting element 1 over the substrate 900, 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.

[0514] Then, the substrate was put into a vacuum evaporation apparatus whose inside was reduced to a pressure of 10 -4 Pa, and vacuum baking at 170 °C for 30 minutes was performed in a heating chamber in the vacuum evaporation apparatus, followed by cooling of the substrate 900 for about 30 minutes.

[0515] Next, the substrate 900 was fixed to a holder provided in the vacuum evaporation apparatus so that the surface on which the first electrode 901 was formed faced downward. In this embodiment, a case where a hole injection layer 911, a hole transport layer 912, a light-emitting layer 913, an electron transport layer 914, and an electron injection layer 915 which constitute the EL layer 902 are sequentially formed by a vacuum evaporation method is described.

[0516] The inside of the vacuum evaporation apparatus was reduced in pressure to 10 -4 After that, 1,3,5-tris(dibenzothiophene-4-yl)benzene (abbreviation: DBT3P-II) and molybdenum oxide were co-evaporated at a ratio of DBT3P-II : molybdenum oxide = 4 : 2 (mass ratio) to form a hole injection layer 911 over the first electrode 901. The thickness thereof was set to 20 nm. Note that co-evaporation is a method in which a plurality of different substances are evaporated at the same time from different evaporation sources.

[0517] Next, 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: BPAFLP) was deposited to a thickness of 20 nm to form a hole transport layer 912.

[0518] Next, a light-emitting layer 913 was formed over the hole transport layer 912.

[0519] In the case of the light-emitting element 1, 2-[3-(benzo[1,2-b:4,5-b']difuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbfPDBq), N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluorene-2-amine (abbreviation: PCBBiF), and [Ir(tBuppm)2(acac)] were co-evaporated so as to satisfy the relationship of 2mBbfPDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.7:0.3:0.05 (mass ratio). The thickness thereof was set to 20 nm. Further, co-evaporation was performed so as to satisfy the relationship of 2mBbfPDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.8:0.2:0.05 (mass ratio) with a thickness of 20 nm, whereby a 40-nm-thick light-emitting layer 913 having a stacked structure was formed.

[0520] In the case of the light-emitting element 2, 2-[3-(benzo[1,2-b:5,4-b']difuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(II)PDBq), PCBBiF, and [Ir(tBuppm)2(acac)] were co-evaporated so as to satisfy the relationship of 2mBbf(II)PDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.7:0.3:0.05 (mass ratio) with a thickness of 20 nm, and then co-evaporation was performed so as to satisfy the relationship of 2mBbf(II)PDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.8:0.2:0.05 (mass ratio) with a thickness of 20 nm, whereby a 40-nm-thick light-emitting layer 913 having a stacked structure was formed.

[0521] In the case of the light-emitting element 3, 2-[3-(benzo[l,2-b:5,6-b']bifuran-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)PDBq), PCBBiF, and [Ir(tBuppm)2(acac)] were co-evaporated so as to satisfy a relationship of 2mBbf(III)PDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.7:0.3:0.05 (mass ratio) in a thickness of 20 nm, and then co-evaporated so as to satisfy a relationship of 2mBbf(III)PDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.8:0.2:0.05 (mass ratio) in a thickness of 20 nm, whereby a 40-nm-thick light-emitting layer 913 having a stacked structure was formed.

[0522] In the case of the light-emitting element 4, 2-[3'-(benzo[l,2-b:5,6-b']bifuran-4-yl)-l,l'-biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mBbf(III)BPDBq), PCBBiF, and [Ir(tBuppm)2(acac)] were co-evaporated so as to satisfy a relationship of 2mBbf(III)BPDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.7:0.3:0.05 (mass ratio) in a thickness of 20 nm, and then co-evaporated so as to satisfy a relationship of 2mBbf(III)BPDBq:PCBBiF:[Ir(tBuppm)2(acac)] = 0.8:0.2:0.05 (mass ratio) in a thickness of 20 nm, whereby a 40-nm-thick light-emitting layer 913 having a stacked structure was formed.

[0523] In the case of the comparative light-emitting element 5, 2-[3'-(dibenzo-thiophene-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), PCBBiF, and [Ir(tBuppm)2(acac)] were co-evaporated so as to satisfy a relationship of 2mDBTBPDBq-II:PCBBiF:[Ir(tBuppm)2(acac)] = 0.7:0.3:0.05 in a thickness of 20 nm, and then co-evaporated so as to satisfy a relationship of 2mDBTBPDBq-II:PCBBiF:[Ir(tBuppm)2(acac)] = 0.8:0.2:0.05 (mass ratio) in a thickness of 20 nm, whereby a 40-nm-thick light-emitting layer 913 having a stacked structure was formed.

[0524] Next, in the case of the light-emitting element 1, 20-nm-thick 2mBbfPDBq was vapor-deposited on the light-emitting layer 913, followed by vapor-deposition of 10-nm-thick Bphen to form the electron-transport layer 914. In the case of the light-emitting element 2, 20-nm-thick 2mBbf(II)PDBq was vapor-deposited on the light-emitting layer 913, followed by vapor-deposition of 10-nm-thick Bphen to form the electron-transport layer 914. In the case of the light-emitting element 3, 20-nm-thick 2mBbf(III)PDBq was vapor-deposited on the light-emitting layer 913, followed by vapor-deposition of 10-nm-thick Bphen to form the electron-transport layer 914. In the case of the light-emitting element 4, 20-nm-thick 2mBbf(III)BPDBq was vapor-deposited on the light-emitting layer 913, followed by vapor-deposition of 10-nm-thick Bphen to form the electron-transport layer 914.

[0525] Further, lithium fluoride was vapor-deposited on the electron-transport layers 914 of the light-emitting elements 1 to 4 to a thickness of 1 nm to form an electron-injection layer 915.

[0526] Finally, aluminum was vapor-deposited on the electron-injection layer 915 to a thickness of 200 nm to form a second electrode 903 used as a cathode, to obtain the light-emitting elements 1 to 4. Note that in the above vapor-deposition processes, vapor-deposition was performed by a resistance heating method.

[0527] Table 1 shows the element structures of the light-emitting elements 1 to 4, the comparative light-emitting element 5, which were obtained by the above steps.

[0528] [Table 1]

[0529]

[0530] * 2mBbfPDBq:PCBBiF: [Ir(tBuppm)2(acac)] (0.7:0.3:0.05 20 nm\0.8:0.2:0.05 20 nm) ** 2mBbf(II)PDBq:PCBBiF: [Ir(tBuppm)2(acac)] (0.7:0.3:0.05 20 nm\0.8:0.2:0.05 20 nm) *** 2mBbf(III)PDBq:PCBBiF: [Ir(tBuppm)2(acac)] (0.7:0.3:0.05 20 nm\0.8:0.2:0.05 20 nm) **** 2mBbf(III)BPDBq:PCBBiF: [Ir(tBuppm)2(acac)] (0.7:0.3:0.05 20 nm\0.8:0.2:0.05 20 nm) ***** 2mDBTBPDBq-II:PCBBiF: [Ir(tBuppm)2(acac)] (0.7:0.3:0.05 20 nm\0.8:0.2:0.05 20 nm)

[0531] Further, the luminescent elements 1 to 4, the comparative luminescent element 5 manufactured were sealed in a glove box in a nitrogen atmosphere in such a manner that the luminescent elements were not exposed to the atmosphere (a sealing material was applied to the periphery of the elements, and UV treatment was performed at the time of sealing and heat treatment at 80°C for 1 hour).

[0532] "Operational characteristics of the luminescent elements 1 to 4, the comparative luminescent element 5"

[0533] The operational characteristics of the luminescent elements 1 to 4 manufactured were measured. In addition, the measurement was performed at room temperature (atmosphere maintained at 25°C).

[0534] FIG. 29 , FIG. 29 , FIG. 30 and FIG. 31 FIGS. 1 to 4 respectively show the current density-luminance characteristics, the voltage-luminance characteristics, the luminance-current efficiency characteristics, and the voltage-current characteristics of the luminescent elements 1 to 4.

[0535] Further, Table 2 below shows the main initial characteristic values of the luminescent elements 1 to 4, the comparative luminescent element 5 at 1000 cd / m 2 nearby. It was confirmed that the comparative luminescent element 5 had good initial characteristics to the same extent as the luminescent elements 1 to 4.

[0536] [Table 2]

[0537]

[0538] Further,FIG. 32 It shows 25mA / cm 2 The current density determines the emission spectrum when current flows through light-emitting elements 1 to 4. For example... FIG. 31 As shown, the emission spectra of light-emitting elements 1 to 4 have a peak around 546 nm, indicating that this spectrum originates from the green emission of the organometallic complex [Ir(tBuppm)2(acac)] used in the EL layer of each light-emitting element. It was confirmed that the emission spectrum of the comparative light-emitting element 5 is also derived from the green emission of [Ir(tBuppm)2(acac)], similar to that of light-emitting elements 1 to 4.

[0539] Next, reliability tests were conducted on light-emitting elements 1 to 4. FIG. 32 The results of the reliability test are shown. FIG. 31 In the graph, the vertical axis represents the normalized luminance (%) when the initial luminance is 100%, while the horizontal axis represents the drive time (h) of the component. Furthermore, in reliability testing, the initial luminance was set to 5000 cd / m². 2 Under the condition that the current density is constant, light-emitting elements 1 to 4 are driven.

[0540] Light-emitting elements 1 to 4 all use a heterocyclic compound according to one aspect of the present invention, therefore, according to FIG. 32 The results show that all light-emitting elements exhibit high reliability. Therefore, it can be concluded that by using the heterocyclic compound of one aspect of this invention, a long service life for light-emitting elements can be achieved.

[0541] In addition, preservation tests were conducted on light-emitting elements 1 to 3 and control light-emitting element 5. During the preservation test, each light-emitting element was not driven and was stored in a constant temperature bath maintained at 100°C. After a specified time, the operating characteristics were measured. After removing the light-emitting elements from the constant temperature bath, the operating characteristics were measured at room temperature (in an atmosphere maintained at 25°C).

[0542] ​ The results show the measurement of the external quantum efficiency of light-emitting elements 1 to 3 and the comparative light-emitting element 5 over time. According to the results, even when light-emitting elements 1 to 3 are maintained at 100°C for an extended period, they retain their initial external quantum efficiency and high heat resistance. On the other hand, it was observed that the external quantum efficiency of the comparative light-emitting element 5 decreased significantly within approximately 10 hours.

[0543] The molecular weight of 2mBbfPDBq for light-emitting element 1, 2mBbf(II)PDBq for light-emitting element 2, and 2mBbf(III)PDBq for light-emitting element 3 are all 562, and the molecular weight of 2mDBTBPDBq-II for comparative light-emitting element 5 is 564. That is, although the respective molecular weights of the light-emitting elements used in the storage test are the same degree, a large difference in heat resistance in the 100°C storage test between light-emitting elements 1 to 3 and comparative light-emitting element 5 is observed.

[0544] The difference between light-emitting elements 1 to 3 and comparative light-emitting element 5 is that light-emitting elements 1 to 3 have a molecular structure of a benzo-bisbenzofuran having a condensed aromatic ring. The difference in heat resistance in the storage test is due to this molecular structure, and it is found that a compound and a light-emitting element having very high heat resistance can be obtained even without increasing the molecular weight, and the effect of using a condensed ring is large.

[0545] Example 6

[0546] In this example, the HOMO level and the LUMO level of a heterocyclic compound 2-[3-(benzo[l,2-b:4,5-b']bisbenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2mBbfPDBq) of one embodiment of the present application represented by Structural Formula (101) were calculated by cyclic voltammetry (CV) measurement.

[0547] [Chemical Formula 65]

[0548]

[0549] As a measurement device, an electrochemical analyzer (ALS Model 600A or 600C manufactured by BAS Inc.) was used. As a solution for CV measurement, dehydrated dimethylformamide (DMF, manufactured by Sigma-Aldrich Inc., 99.8%, catalog number: 227056) was used as a solvent, and tetra-n-butylammonium perchlorate (n-Bu4NClO4, manufactured by Tokyo Chemical Industry Co., Ltd., catalog number: T0836) as a supporting electrolyte was dissolved in the solvent so that the concentration of tetra-n-butylammonium perchlorate was 100 mmol / L. In addition, the measurement object was dissolved in the solvent so that the concentration was 2 mmol / L. Further, a platinum electrode (manufactured by BAS Inc., PTE platinum electrode) was used as a working electrode, a platinum electrode (manufactured by BAS Inc., Pt counter electrode for VC-3 (5 cm)) was used as an auxiliary electrode, and an Ag / Ag +Electrode (manufactured by BAS, RE7 non-aqueous solvent reference electrode). Also, the measurement was performed at room temperature (20 to 25°C). The scan rate at the time of CV measurement was unified to 0.1 V / sec, and the oxidation potential Ea [V] and the reduction potential Ec [V] with respect to the reference electrode were measured. Ea is the intermediate potential between the oxidation-reduction wave, and Ec is the intermediate potential between the reduction-oxidation wave. Here, it is known that the potential energy with respect to the vacuum energy level of the reference electrode used in the present example is -4.94 [eV], and therefore the HOMO level [eV] = -4.94 - Ea and the LUMO level [eV] = -4.94 - Ec are respectively obtained using these two formulas. The CV measurement was repeated 100 times, and the oxidation-reduction wave in the 100th measurement was compared with that in the 1st measurement, to investigate the electrical stability of the compound.

[0550] As a result, in the measurement of the oxidation potential Ea [V] of 2mBbfPDBq, no clear oxidation peak was obtained in the range of 0.2 to 1.5 eV. On the other hand, it was known that the LUMO level was -2.97 eV. In the repeated measurement of the reduction-oxidation wave, the peak intensity of the oxidation-reduction wave after 100 cycles remained 73% of that of the oxidation-reduction wave in the 1st cycle, and therefore it was confirmed that the reduction resistance of 2mBbfPDBq was very high.

[0551] Also, thermogravimetry-differential thermal analysis (TG-DTA) was performed on 2mBbfPDBq. In the measurement, a high-vacuum differential type differential thermal balance (manufactured by Bruker AXS, TG-DTA 2410SA) was used. When the measurement was performed at a temperature increase rate of 10°C / min under a nitrogen stream (flow rate: 200 mL / min) and normal pressure, it was known from the relationship between the weight and the temperature (thermogravimetry) that the 5% weight loss temperature of 2mBbfPDBq was about 442°C. This indicates that the heat resistance of 2mBbfPDBq is high.

[0552] Also, differential scanning calorimeter (DSC measurement) was performed using Pyris 1 DSC manufactured by PerkinElmer, Inc. In the differential scanning calorimeter, the following operations were continuously performed twice, and the measurement result of the second time was adopted: the temperature was increased from -10°C to 370°C at a temperature increase rate of 50°C / min, then the temperature was held at the same temperature for 1 minute, and then the temperature was decreased from 370°C to -10°C at a temperature decrease rate of 50°C / min. It was known from the DSC measurement that the glass transition temperature of 2mBbfPDBq was 147°C, and 2mBbfPDBq is a compound having high heat resistance.

[0553] Next, the 2mBbf PDBq obtained in the present example was subjected to mass spectrometry analysis by liquid chromatography mass spectrometry (LC / MS analysis).

[0554] In the LC / MS analysis, LC (liquid chromatography) separation was performed using Acquity UPLC (registered trademark) manufactured by Waters Corporation, and MS analysis (mass analysis) was performed using Xevo G2 Tof MS manufactured by Waters Corporation. The column used in the LC separation was Acquity UPLC BEH C8 (2.1 x 100 mm, 1.7 μm), and the column temperature was 40°C. In the mobile phase, acetonitrile was used as mobile phase A, and 0.1% formic acid aqueous solution was used as mobile phase B. In addition, as a sample, 2mBbf PDBq of an arbitrary concentration was dissolved in N-methyl-2-pyrrolidone, and diluted with acetonitrile to adjust, and the injection amount was set to 5.0 μL.

[0555] In the LC separation, a gradient method in which the composition of the mobile phase was changed was used, and the ratio of mobile phase A:mobile phase B was 65:35 at 0 minutes to 1 minute after the start of measurement, and then the composition was changed, and the ratio of mobile phase A:mobile phase B was 95:5 at 10 minutes after the start of measurement, and the total analysis time was 10 minutes. The composition was changed linearly.

[0556] In the MS analysis, ionization was performed by an electro spray ionization (ESI) method. The capillary voltage was set to 3.0 kV, the sample cone hole voltage was set to 30 V, and detection was performed in the positive mode. In addition, the mass range detected was m / z = 100 to 1200.

[0557] When LC / MS measurement was performed under the above conditions, ions derived from 2mBbf PDBq were detected at mass-to-charge ratio (m / z) = 563.175 ([M+H + ] and 562.175 for 2mBbf PDBq). Next, the ions at mass-to-charge ratio (m / z) = 563.175 (precursor ions) were dissociated by collision with argon gas in a collision cell. The energy at which the precursor ions collided with argon (collision energy) was 50 eV and 70 eV. ​ a mass spectrum showing the product ions generated by collision of the precursor ions with argon gas when the collision energy was 50 eV, which was detected by a time-of-flight mass spectrometer (TOF) type detector, ​ a mass spectrum when the collision energy was 70 eV.

[0558] From the results shown in FIG. 6, it was found that the daughter ions of 2mBbfPDBq represented by structural formula (101) were detected mainly around m / z = 536.165, around m / z = 345.091, around m / z = 334.098, around m / z = 305.096, around m / z = 229.076, around m / z = 202.066, and around m / z = 177.070. ​ ​ From the results shown in FIG. 6, it was found that the daughter ions of 2mBbfPDBq represented by structural formula (101) were detected mainly around m / z = 536.165, around m / z = 345.091, around m / z = 334.098, around m / z = 305.096, around m / z = 229.076, around m / z = 202.066, and around m / z = 177.070. ​ ​ The results shown in FIG. 6 are typical results derived from 2mBbfPDBq, and thus can be said to be important data for determining 2mBbfPDBq contained in a mixture.

[0559] ​​It is presumed that the sub-ion around m / z = 536.165 is a structure in which the ring containing nitrogen of dibenzo [f, h] quinoxaline in the compound of Structural Formula (101) represented by the following formula (a) is cleaved. Further, it is presumed that the sub-ion around m / z = 345.091 is dibenzo [f, h] quinoxaline generated by cleavage of the bond at the 2-position of dibenzo [f, h] quinoxaline in the compound of Structural Formula (101) represented by the following formula (b); the sub-ion around m / z = 334.098 is 6-phenylbenzo [1, 2-b: 4, 5-b'] dibenzofuran generated by cleavage of the bond at the 2-position of dibenzo [f, h] quinoxaline in the compound of Structural Formula (101) represented by the following formula (c); the sub-ion around m / z = 305.096 is 2-phenyl dibenzo [f, h] quinoxaline generated by cleavage of the bond at the 6-position of benzo [1, 2-b: 4, 5-b'] dibenzofuran in the compound of Structural Formula (101) represented by the following formula (d); the sub-ion around m / z = 229.076 is dibenzo [f, h] quinoxaline generated by cleavage of the bond at the 2-position of dibenzo [f, h] quinoxaline in the compound of Structural Formula (101) represented by the following formula (e); the sub-ion around m / z = 202.066 is an ion generated by further cleavage of the sub-ion around m / z = 536.165 represented by the following formula (f); and the sub-ion around m / z = 177.070 is an ion generated by further cleavage of the sub-ion around m / z = 536.165 represented by the following formula (g). In particular, the ion represented by formula (a) of the ion generated by cleavage of the ring containing two nitrogens of dibenzo [f, h] quinoxaline and the ions represented by formulae (b) to (d) of the ion generated by cleavage of the bond between the rings in the compound of Structural Formula (101) are one of the characteristics of 2mBbfPDBq, and thus it can be said that they are important data for determining 2mBbfPDBq contained in the mixture.

[0560] [Chemical Formula 66]

[0561]

[0562] Example 7

[0563] In this example, the HOMO level and the LUMO level of the heterocyclic compound 2-[3-(benzo[1,2-b:5,4-b']dibenzofuran-6-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2mBbf(II)PDBq) of one embodiment of the present application represented by the following Structural Formula (107) were calculated by cyclic voltammetry (CV). The calculation method is shown below.

[0564] [Chemical Formula 67]

[0565]

[0566] The HOMO level and the LUMO level of 2mBbf (II) PDBq were calculated by cyclic voltammetry (CV). The method of CV measurement, the method of calculation of the HOMO level and the LUMO level were the same as those of Example 6.

[0567] As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf (II) PDBq, no clear oxidation peak was obtained in the range of -0.2 eV to 1.5 eV. On the other hand, it was found that the LUMO level was -2.94 eV. In the repeated measurement of the reduction-oxidation wave, the peak intensity of the reduction-oxidation wave after 100 cycles remained 87% of the reduction-oxidation wave of the 1st cycle, and thus it was confirmed that the reduction resistance of 2mBbf (II) PDBq was very high.

[0568] In addition, 2mBbf (II) PDBq was subjected to thermogravimetric-differential thermal analysis. The analysis method was the same as that of Example 6. According to the measurement result, it was found that the 5% weight loss temperature of 2mBbf (II) PDBq was about 459°C. This indicates that the heat resistance of 2mBbf (II) PDBq is high.

[0569] Example 8

[0570] In the present example, the HOMO level and the LUMO level of a heterocyclic compound of one embodiment of the present application represented by the following structural formula (149), 2-[3-(benzo[l,2-b:5,6-b']biferan-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2mBbf (III) PDBq), were calculated by cyclic voltammetry (CV). Hereinafter, the method of calculation is shown.

[0571] [Chemical Formula 68]

[0572]

[0573] The HOMO level and the LUMO level of 2mBbf (III) PDBq were calculated by cyclic voltammetry (CV). The method of CV measurement, the method of calculation of the HOMO level and the LUMO level were the same as those of Example 6.

[0574] As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf (III) PDBq, no clear oxidation peak was obtained in the range of 0 eV to 1.5 eV. On the other hand, it was found that the LUMO level was -2.95 eV. In the repeated measurement of the reduction-oxidation wave, the peak intensity of the reduction-oxidation wave after 100 cycles remained 79% of the reduction-oxidation wave of the 1st cycle, and thus it was confirmed that the reduction resistance of 2mBbf (III) PDBq was very high.

[0575] In addition, thermogravimetry-differential thermal analysis was performed on 2mBbf(III)PDBq. The analysis method was the same as in Example 6. From the measurement results, it was found that the 5% weight loss temperature of 2mBbf(III)PDBq was about 454°C. This indicates that 2mBbf(III)PDBq has high heat resistance.

[0576] Example 9

[0577] In this example, the HOMO level and the LUMO level of a heterocyclic compound 2-[3'-(benzo[l,2-b:5,6-b']biferan-4-yl)-l,l'-biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mBbf(III)BPDBq) of one embodiment of the present application represented by Structural Formula (150) below were calculated by cyclic voltammetry (CV). The calculation method is shown below.

[0578] [Chemical Formula 69]

[0579]

[0580] The HOMO level and the LUMO level of 2mBbf(III)BPDBq were calculated by cyclic voltammetry (CV). The method of CV measurement, the calculation method of the HOMO level, and the calculation method of the LUMO level were the same as in Example 6.

[0581] As a result, in the measurement of the oxidation potential Ea [V] of 2mBbf(III)BPDBq, no clear oxidation peak was obtained in the range of 0.1 eV to 1.5 eV. On the other hand, it was found that the LUMO level was -2.98 eV. In the repeated measurement of the oxidation-reduction wave, the peak intensity of the oxidation-reduction wave after 100 cycles was 71% of the oxidation-reduction wave of the first cycle, and thus it was confirmed that 2mBbf(III)BPDBq has very high reduction resistance.

[0582] Symbol Explanation

[0583] 101 first electrode

[0584] 102 EL layer

[0585] 103 second electrode

[0586] 111 hole injection layer

[0587] 112 hole transport layer

[0588] 113 light-emitting layer

[0589] 114 electron transport layer

[0590] 115 electron injection layer

[0591] 201 first electrode

[0592] 202(1) first EL layer

[0593] 202(2) second EL layer

[0594] 202(n-1) (n-1)th EL layer

[0595] 202(n) nth EL layer

[0596] 204 second electrode

[0597] 205 charge generation layer

[0598] 205(1) first charge generation layer

[0599] 205(2) second charge generation layer

[0600] 205(n-2) (n-2)th charge generation layer

[0601] 205(n-1) (n-1)th charge generation layer

[0602] 301 element substrate

[0603] 302 pixel portion

[0604] 303 driver circuit portion (source line driver circuit)

[0605] 304a, 304b driver circuit portion (gate line driver circuit)

[0606] 305 sealing agent

[0607] 306 sealing substrate

[0608] 307 wiring

[0609] 308 FPC (flexible printed circuit)

[0610] 309 FET

[0611] 310 FET

[0612] 312 current control FET

[0613] 313a, 313b first electrode (anode)

[0614] 314 insulator

[0615] 315 EL layer

[0616] 316 second electrode (cathode)

[0617] 317a, 317b light emitting element

[0618] 318 space

[0619] 320a, 320b conductive film

[0620] 321, 322 region

[0621] 323 lead wire

[0622] 324 colored layer (color filter)

[0623] 325 black layer (black matrix)

[0624] 326, 327, 328 FET

[0625] 401 substrate

[0626] 402 first electrode

[0627] 404 second electrode

[0628] 403a, 403b, 403c EL layer

[0629] 405 light emitting element

[0630] 406 insulating film

[0631] 407 partition wall

[0632] 900 substrate

[0633] 901 first electrode

[0634] 902 EL layer

[0635] 903 second electrode

[0636] 911 hole injection layer

[0637] 912 hole transport layer

[0638] 913 light emitting layer

[0639] 914 electron transport layer

[0640] 915 electron injection layer

[0641] 2000 touch panel

[0642] 2501 display panel

[0643] 2502R pixel

[0644] 2502t transistor

[0645] 2503c capacitor

[0646] 2503g scan line driver circuit

[0647] 2503t transistor

[0648] 2509 FPC

[0649] 2510 substrate

[0650] 2511 wiring

[0651] 2519 terminal

[0652] 2521 insulating layer

[0653] 2528 insulator

[0654] 2550R light emitting element

[0655] 2560 sealing layer

[0656] 2567BM light-blocking layer

[0657] 2567p anti-reflection layer

[0658] 2567R colored layer

[0659] 2570 substrate

[0660] 2590 substrate

[0661] 2591 electrode

[0662] 2592 electrode

[0663] 2593 insulating layer

[0664] 2594 wiring

[0665] 2595 touch sensor

[0666] 2597 adhesive layer

[0667] 2598 wiring

[0668] 2599 terminal

[0669] 2601 pulse voltage output circuit

[0670] 2602 current detection circuit

[0671] 2603 capacitor

[0672] 2611 transistor

[0673] 2612 transistor

[0674] 2613 transistor

[0675] 2621 electrode

[0676] 2622 electrode

[0677] 4000 lighting device

[0678] 4001 substrate

[0679] 4002 light-emitting element

[0680] 4003 substrate

[0681] 4004 electrode

[0682] 4005 EL layer

[0683] 4006 electrode

[0684] 4007 electrode

[0685] 4008 electrode

[0686] 4009 auxiliary wiring

[0687] 4010 insulating layer

[0688] 4011 sealing substrate

[0689] 4012 sealing agent

[0690] 4013 desiccant

[0691] 4015 diffusion plate

[0692] 4100 lighting device

[0693] 4200 lighting device

[0694] 4201 substrate

[0695] 4202 light-emitting element

[0696] 4204 electrode

[0697] 4205 EL layer

[0698] 4206 electrode

[0699] 4207 electrode

[0700] 4208 electrode

[0701] 4209 auxiliary wiring

[0702] 4210 insulating layer

[0703] 4211 sealing substrate

[0704] 4212 sealant

[0705] 4213 barrier film

[0706] 4214 planarization film

[0707] 4215 diffusion plate

[0708] 4300 lighting device

[0709] 5101 lamp

[0710] 5102 hub

[0711] 5103 door

[0712] 5104 display section

[0713] 5105 steering wheel

[0714] 5106 gear lever

[0715] 5107 seat

[0716] 5108 rearview mirror

[0717] 7100 television device

[0718] 7101 frame

[0719] 7103 display section

[0720] 7105 stand

[0721] 7107 display section

[0722] 7109 operation key

[0723] 7110 remote control operation machine

[0724] 7201 main body

[0725] 7202 frame

[0726] 7203 display section

[0727] 7204 keyboard

[0728] 7205 external connection port

[0729] 7206 pointing device

[0730] 7302 frame

[0731] 7304 display section

[0732] 7305 icon indicating time

[0733] 7306 other icon

[0734] 7311 operation button

[0735] 7312 operation button

[0736] 7313 connection terminal

[0737] 7321 wrist band

[0738] 7322 band buckle

[0739] 7400 mobile phone

[0740] 7401 frame

[0741] 7402 display section

[0742] 7403 operation button

[0743] 7404 external connection section

[0744] 7405 speaker

[0745] 7406 microphone

[0746] 7407 camera

[0747] 7500(1), 7500(2) frame

[0748] 7501(1), 7501(2) first surface

[0749] 7502(1), 7502(2) second surface

[0750] 8001 lighting device

[0751] 8002 lighting device

[0752] 8003 lighting device

[0753] 9310 portable information terminal

[0754] 9311 display section

[0755] 9312 display region

[0756] 9313 hinge section

[0757] 9315 frame

Claims

1. A light-emitting element comprising a light-emitting layer comprising a compound, a substance having a hole-transport property, and a light-emitting substance, wherein the compound is represented by General Formula (Gl): ， DBq represents a substituted or unsubstituted dibenzo[ f , h ] quinoxalinyl group, Ar 1 represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, n Represents 0 or 1, Ar 2 represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzodibenzofuranyl group represented by any one of the following Chemical Formulae (Al) to (A3), The substituted dibenzo[ f , h The substituents of the quinoxalinyl group and the substituents of the substituted aryl group having 6 to 13 carbon atoms are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms. and a substituent of the substituted benzodibenzofuranyl group is any one of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, and an aryl group having 6 to 13 carbon atoms.

2. A light-emitting element comprising a light-emitting layer and an electron-transport layer, wherein the electron-transport layer comprises a compound, the compound is represented by General Formula (Gl): ， DBq represents a substituted or unsubstituted dibenzo[ f , h ] quinoxalinyl group, Ar 1 represents a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, n Represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, A represents a substituted or unsubstituted benzodibenzofuranyl group represented by any one of the following Chemical Formulae (Al) to (A3), The substituted dibenzo[ f , h The substituents of the quinoxalinyl group and the substituents of the substituted aryl group having 6 to 13 carbon atoms are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms. and a substituent of the substituted benzodibenzofuranyl group is any one of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, and an aryl group having 6 to 13 carbon atoms.

3. The light-emitting element according to claim 1 or 2, wherein the compound is represented by General Formula (G2): ， and R 1 independently represent any one of hydrogen, an alkyl group having 1 to 4 carbon atoms and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms. 9 independently represent any one of hydrogen, an alkyl group having 1 to 4 carbon atoms and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms.

4. A light-emitting element comprising a first light-emitting layer and a second light-emitting layer, wherein the first light-emitting layer comprises a compound and a light-emitting substance, the compound is represented by General Formula (G2): ， A represents a substituted or unsubstituted benzodibenzofuranyl group represented by any one of the following Chemical Formulae (Al) to (A3), R 1 to R 9 independently represent any one of hydrogen, an alkyl group having 1 to 4 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 13 carbon atoms, Ar 1 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, n Represents 0 or 1, Ar 2 represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, The substituted dibenzo[ f , h The substituents of the quinoxalinyl group and the substituents of the substituted aryl group having 6 to 13 carbon atoms are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms. and a substituent of the substituted benzodibenzofuranyl group is any one of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, and an aryl group having 6 to 13 carbon atoms.

5. The light-emitting element according to any one of claims 1, 2, and 4, wherein the arylene group having 6 to 13 carbon atoms is represented by any one of structural formulae (al) to (al5): 。 6. The light-emitting element according to any one of claims 1, 2, and 4, wherein the compound and the substance having a hole-transport property are capable of forming an exciplex.

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