Organic light-emitting device and application thereof

Abstract

The invention provides an organic light-emitting device and application thereof, and belongs to the technical field of organic light-emitting devices, and the organic light-emitting device is prepared by combining a compound as shown in a formula I in a hole transport region and a blue light doping material as shown in a formula II in a light-emitting layer. The compound can still have excellent luminous efficiency, long service life and lower driving voltage under high brightness.

Description

Technical Field

[0001] The invention belongs to the technical field of organic electroluminescent devices and relates to an organic electroluminescent device and an application thereof. Background Art

[0002] Organic light emitting diode (OLED) has the advantages of being thin and light, active light emission, wide viewing angle, fast response, low energy consumption, excellent low temperature and shock resistance, and potential flexible design. OLED is a fully solid-state device with no vacuum cavity and no liquid components, so it is not afraid of vibration and is easy to use. In addition, the high resolution, wide viewing angle and wide operating temperature range make the use of OLED devices more and more extensive.

[0003] Blue OLED is the key to achieving full-color display. By combining red, green and blue OLEDs, colorful images can be generated, which are widely used in display devices such as TVs, mobile phones, and tablets. Blue organic electroluminescent devices are the weak point in the development of full-color OLEDs. Up to now, the efficiency and life of blue light devices have been difficult to improve comprehensively. Long-term use may cause life attenuation problems, which need to be solved by optimizing materials and device structures.

[0004] Therefore, providing an OLED display device with excellent luminous efficiency, long life and low driving voltage is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide an organic electroluminescent device and its application. The present invention is an organic electroluminescent device prepared by combining a compound represented by Formula I in the hole transport region and a blue light doping material represented by Formula II in the light emitting layer, wherein the compound can still have excellent luminous efficiency, long life and low driving voltage at high brightness.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides an organic electroluminescent device, comprising a first electrode, a second electrode facing the first electrode, a light-emitting layer between the first electrode and the second electrode, and a hole transport region between the first electrode and the light-emitting layer;

[0008] The hole transport region comprises a compound shown in Formula I;

[0009]

[0010] In formula I, X is O or S;

[0011] Ar is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl and phenanthryl, and Ar is fused with the adjacent benzene ring on the parent nucleus, and the fusion position is 1,2, 2,3 or 3,4 of the benzene ring;

[0012] L is selected from a linker or When L is a connecting bond, the N atom is directly connected to the benzene ring;

[0013] R3 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur;

[0014] R1 is selected from any one of hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur;

[0015] Ar1 and Ar2 are each independently selected from any one of a substituted or unsubstituted 3-30-membered heterocycloalkyl, a substituted or unsubstituted C6-C30 aryl and a substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur.

[0016] Further preferably, L is selected from a connecting bond or any one of the following groups:

[0017]

[0018] * represents the attachment site of the group.

[0019] More preferably, R1 is selected from hydrogen or any one of the following groups:

[0020]

[0021] * represents the attachment site of the group.

[0022] Further preferably, Ar1 and Ar2 are the same or different from each other and are independently selected from one or a combination of several of the following groups:

[0023]

[0024] * represents the attachment site of the group.

[0025] The doping material in the light-emitting layer is a compound shown in Formula II:

[0026]

[0027] In Formula II,

[0028] R4 is selected from substituted or unsubstituted diarylamine, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl;

[0029] R a -R d The same as or different from each other, and each independently selected from substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl;

[0030] R4, R a -R d Each independently represents a monosubstituted, disubstituted, trisubstituted, tetrasubstituted, pentasubstituted or unsubstituted group;

[0031] When R4 is selected from diarylamine, Formula II is selected from the following Formula II-1, R a When selected from substituted or unsubstituted C6-C30 aryl, Formula II is selected from the following Formula II-2:

[0032]

[0033] The substituents in the substituted groups in Formula I and Formula II are selected from any one or a combination of at least two of deuterium, C1-C30 alkyl or C6-C30 aryl.

[0034] Further preferably, the compound represented by formula I can be specifically illustrated by the following compounds, but is not limited thereto:

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041] Preferably, the doping material is selected from the compounds shown in Formula II and can be specifically illustrated by the following compounds, but is not limited thereto:

[0042]

[0043]

[0044]

[0045] Based on the boron-nitrogen doped compound, when R4 is a diarylamine group, it can effectively improve the device efficiency when combined with the second hole transport layer material of the present application. a When it is an aromatic group, it is substituted at the ortho position of the phenyl group and can be used in combination with the second hole transport layer material of the present application to significantly improve the device life.

[0046] In the present invention, the compounds of formula I and formula II are compounds known in the art.

[0047] For raw materials that are not disclosed, those skilled in the art can synthesize them by using the classic Suzuki coupling reaction (Suzuki reaction) and Buchwald-Hartwig coupling reaction (Buchwald-Hartwig reaction), and apply them to the present invention.

[0048] The compound of formula I described in the present invention can be synthesized by referring to the following reaction scheme:

[0049]

[0050] Wherein, Hal1, Hal2 and Hal3 are each independently selected from halogen.

[0051] The specific steps of the above synthetic route are as follows:

[0052] (1) After raw material A and raw material B are dissolved in toluene, Pd2(dba)3 (tri(dibenzylideneacetone)dipalladium), P(t-Bu)3 (tri(tert-butyl)phosphine) and t-BuONa (sodium tert-butoxide) are added under N2 atmosphere, the temperature is raised to 105-115°C and stirred for reaction for 8-12 hours. After the reaction is completed, diatomaceous earth is used for hot filtration to remove salt and catalyst. After the filtrate is cooled to room temperature, distilled water is added to the filtrate for washing. After separation, the organic phase is retained, the aqueous phase is extracted with ethyl acetate, and the combined organic layer is dried with magnesium sulfate, and the solvent is removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether is used as an eluent, and the remaining substance is purified by column chromatography to obtain the compound shown in Intermediate 1.

[0053] (2) After the intermediate 1 and the raw material C are dissolved in toluene, Pd2(dba)3, P(t-Bu)3 and t-BuONa are added under a N2 atmosphere, the temperature is raised to 105-115°C and the reaction is stirred for 8-12 hours. After the reaction is completed, diatomaceous earth is used for hot filtration to remove salt and catalyst. After the filtrate is cooled to room temperature, distilled water is added to the filtrate for washing. After separation, the organic phase is retained, the aqueous phase is extracted with ethyl acetate, and then the combined organic layer is dried with magnesium sulfate, and the solvent is removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether is used as an eluent, and the remaining substance is purified by column chromatography to obtain the compound represented by the intermediate 2.

[0054] (3) Under N2 protection, the intermediate 2, the raw material D, tetrakis(triphenylphosphine)palladium and potassium carbonate are added to a mixed solvent of toluene, ethanol and water respectively, and the temperature is raised to 90-100°C for reaction for 8-10 hours. After the reaction is completed, the mixture is cooled to room temperature. After the solid is precipitated, it is filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake is dried and placed in a methanol solution for recrystallization to obtain the compound represented by the above general formula 1.

[0055] The compound of formula II described in the present invention can be synthesized by referring to the following reaction scheme:

[0056]

[0057] The flask containing raw material a, raw material b, Pd2(dba)3, P(t-Bu)3, NaOtBu and toluene solution was heated to 110-120°C and stirred for 8-10 hours, the reaction solution was cooled to room temperature, and water and ethyl acetate were added to separate the liquid layer. The solvent was then distilled off under reduced pressure and purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate=50% / 50% (volume / volume)) to obtain the compound shown in intermediate 1.

[0058] The flask containing intermediate 1, raw material c, Pd2(dba)3, P(t-Bu)3, NaOtBu and toluene solution is heated to 110-120 ℃ and stirred for 8-10 hours. The reaction solution is cooled to room temperature, and water and ethyl acetate are added to separate the liquid layer. Then the solvent is distilled off under reduced pressure and purified by silica gel column chromatography (developing agent: hexane / ethyl acetate=50% / 50% (volume / volume)) to obtain the compound shown in intermediate 2.

[0059] Under nitrogen atmosphere at -40 ℃, tert-butyl lithium pentane solution is added to the flask containing intermediate 2 and tert-butylbenzene. After completion of the dropwise addition, the temperature is raised to 70-80 ℃, and the mixture is stirred for 1-2 hours, and pentane is distilled off. After cooling to -40 ℃, boron tribromide is added thereto, and the mixture is raised to room temperature and stirred for 1-2 hours. Thereafter, the mixture is cooled to 0 ℃ again, and N, N-diisopropylethylamine is added thereto and stirred at room temperature, and then stirred at 90-100 ℃ for 2-3 hours. The reaction solution is cooled to 0 ℃, and potassium acetate saturated solution and ethyl acetate are added thereto to separate the liquid layer. The solvent is then distilled off under reduced pressure. It is purified by silica gel column chromatography (developing solvent: hexane / dichloromethane=40 / 1 (volume / volume)) to obtain the compound shown in chemical formula II.

[0060] Preferably, the hole transport region at least includes a hole injection layer, a first hole transport layer, and a second hole transport layer, and the second hole transport layer is a compound represented by Formula I.

[0061] The organic electroluminescent device of the present invention can be a top-emitting type, a bottom-emitting type or a bidirectional-emitting type. The device of the present invention can be used in an organic light-emitting device, an organic solar cell, an electronic paper, an organic photoreceptor or an organic thin film transistor.

[0062] The organic light-emitting device may have a structure including a hole injection layer, a hole transport layer, an electron blocking layer, a second hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc. as organic layers. However, the structure of the organic light-emitting element is not limited thereto, and may include fewer or more organic layers.

[0063] The organic light emitting device can be manufactured by sequentially stacking a first electrode, an organic layer, and a second electrode on a substrate, and can be manufactured by a physical vapor deposition (PVD) method such as sputtering or electron beam evaporation.

[0064] A first electrode is formed by vapor-depositing a metal or a conductive metal oxide or an alloy thereof on a substrate, an organic layer including a hole injection layer, a hole transport layer, a light-emitting layer and an electron transport layer is formed on the first electrode, and then a substance that can be used as a second electrode is vapor-deposited on the organic layer. In addition to this method, an organic light-emitting device can also be manufactured by vapor-depositing a second electrode substance, an organic layer, and a first electrode substance on a substrate in sequence.

[0065] In addition, when manufacturing an organic light-emitting device (or element), the compounds represented by the chemical formula I and formula II can be formed into an organic layer by not only vacuum evaporation but also solution coating. The so-called solution coating method refers to spin coating, dip coating, blade coating, inkjet printing, screen printing, spraying, roller coating, etc., but is not limited thereto.

[0066] In the present invention, the first electrode is an anode, and the second electrode is a cathode.

[0067] As the anode material, in order to enable holes to be smoothly injected into the organic layer, a material with a large work function is preferably used. Specific examples of the anode material that can be used in the present invention include metals such as vanadium, chromium, copper, zinc, gold, or their alloys; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO); combinations of metals and oxides such as ZnO:Al or SnO2:Sb; conductive polymers such as polypyrrole and polyaniline, etc.

[0068] As the cathode material, in order to facilitate the injection of electrons into the organic layer, a material with a small work function is preferably used. Specific examples of cathode materials include metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or alloys thereof: multilayer structures such as LiF / Al or LiO2 / Al, and Mg / Ag.

[0069] The hole transport region means a region in which holes are transported between the first electrode and the light-emitting layer. The hole transport region is a region that receives holes from the hole injection layer and transports the holes to the light-emitting layer. The hole transport region may be placed between the anode (or the hole injection layer) and the light-emitting layer. The hole transport region may be used to smoothly move holes transferred from the anode to the light-emitting layer and block electrons transferred from the cathode to remain in the light-emitting layer.

[0070] In the present invention, the hole injection layer is preferably a p-doped hole injection layer, which means a hole injection layer doped with a p-dopant. The p-dopant is a material that can impart p-type semiconductor characteristics. The p-type semiconductor characteristics mean the characteristics of injecting holes or transporting holes at the HOMO energy level, that is, the characteristics of a material with high hole conductivity.

[0071] The second hole transport layer can be placed between the anode and the light-emitting layer, or between the cathode and the light-emitting layer. When the second hole transport layer is placed between the anode and the light-emitting layer, it can be used to promote hole injection and / or hole transport, or to prevent electron overflow. When the second hole transport layer is placed between the cathode and the light-emitting layer, it can be used to promote electron injection and / or electron transport, or to prevent hole overflow.

[0072] The light-emitting material of the light-emitting layer is a material that can receive holes and electrons from the hole transport layer and the electron transport layer, respectively, and combine them to emit light in the visible light region, and is preferably a material with high quantum efficiency for fluorescence or phosphorescence.

[0073] The electron transport region may include at least one of an electron buffer layer, a hole blocking layer, an electron transport layer, and an electron injection layer, and preferably at least one of an electron transport layer and an electron injection layer. The electron transport region is a layer that can improve the problem of degradation of luminous brightness due to changes in current characteristics in the device when the device is exposed to high temperature during the process of manufacturing the panel, and it can control charge flow characteristics.

[0074] Except for the specific combination of the dopant material of formula I in the second hole transport layer and the dopant material of formula II in the light emitting layer disclosed herein, there is no special limitation on the materials of other layers in the OLED device. Existing hole injection materials, hole transport materials, host materials, hole blocking layer materials, electron transport layer materials and electron injection materials can be used.

[0075] Hole injection layer materials include metal porphyrins, oligothiophenes, arylamine derivatives, hexanitrile hexaazatriphenylene organics, quinacridone organics, perylene organics, anthraquinone, polyaniline and polythiophene conductive polymers, etc. P-doped P dopants can be exemplified by the following compounds, but are not limited thereto:

[0076]

[0077]

[0078] The first hole transport material can be selected from arylamine derivatives, conductive polymers, and block copolymers having both conjugated and non-conjugated parts. Specifically, the first hole transport layer material is selected from the following compounds, but is not limited thereto:

[0079]

[0080]

[0081] The second hole transport layer of the present invention is a compound represented by general formula I.

[0082] The main material preferably uses the following anthracene compounds, but is not limited thereto:

[0083]

[0084] The doping material of the present invention is a compound represented by general formula II.

[0085] The material of the electron transport layer (hole blocking layer) can be oxazole, imidazole, thiazole, triazine derivatives, metal chelates, quinoline derivatives, oxaline derivatives, diazanthracene derivatives, diazine derivatives, silicon-containing heterocyclic compounds, perfluorinated oligomers, etc. Specifically, the electron transport layer material is selected from the following compounds, but is not limited thereto:

[0086]

[0087] The electron injection layer materials specifically include fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenyl methane, anthrone, and their derivatives, metal complexes, and nitrogen-containing five-membered ring derivatives, but are not limited thereto.

[0088] In another aspect, the present invention provides a display panel, comprising the organic electroluminescent device as described above.

[0089] In another aspect, the present invention provides use of the organic electroluminescent device as described above in an organic light-emitting device, an organic solar cell, an electronic paper, an organic photoreceptor or an organic thin film transistor.

[0090] Compared with the prior art, the present invention has the following beneficial effects:

[0091] The present invention is an organic electroluminescent device prepared by combining a second hole transport layer of the compound represented by formula I of the present invention and a doping material in the light-emitting layer of the blue light doping material represented by formula II of the present invention. The compound of the present invention as the second hole transport layer is matched with the doping material represented by formula II to have a more suitable HOMO energy level, so that excitons are more effectively transferred, so that the device has excellent performance, lower driving voltage and solves the problems of life attenuation and efficiency reduction of organic electroluminescent devices. DETAILED DESCRIPTION

[0092] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0093] Example 1

[0094]

[0095] After raw material A (1.0 eq, CAS: 125404-00-4) and raw material B (1.0 eq, CAS: 204530-94-9) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under N2 atmosphere, the temperature was raised to 115°C and stirred for reaction for 12 h. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (yield: 80.21%);

[0096] After the intermediate 1 (1.0 eq) and the raw material C (1.0 eq, CAS: 108313-41-3) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under a N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 8 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in the intermediate 2 (yield: 75.34%).

[0097] Under N2 protection, intermediate 2 (1.0 eq), raw material D (1.0 eq, CAS: 1446515-26-2), tetrakis(triphenylphosphine)palladium (0.01 eq) and potassium carbonate (2.0 eq) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, it was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake was dried and placed in a methanol solution for recrystallization to obtain compound 1; (yield: 78.52%).

[0098] The obtained compound 1 was tested and analyzed, and the results were as follows:

[0099] HPLC purity: >99.95%.

[0100] MS (ESI, m / Z): [M+H]+: 713.36.

[0101] Elemental Analysis:

[0102] Calculated values: C, 90.85; H, 4.94; N, 1.96; O, 2.24.

[0103] The test values ​​are: C, 90.16; H, 5.45; N, 2.28; O, 2.53.

[0104] Example 2

[0105]

[0106] After raw material A (1.0 eq, CAS: 125404-00-4) and raw material B (1.0 eq, CAS: 204530-94-9) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under N2 atmosphere, the temperature was raised to 115°C and stirred for reaction for 12 h. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (yield: 77.58%);

[0107] After the intermediate 1 (1.0 eq) and the raw material C (1.0 eq, CAS: 108313-41-3) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under a N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 8 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in the intermediate 2 (yield: 78.29%).

[0108] Under N2 protection, intermediate 2 (1.0 eq), raw material D (1.0 eq, CAS: 1548470-92-3), tetrakis(triphenylphosphine)palladium (0.01 eq) and potassium carbonate (2.0 eq) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, it was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake was dried and placed in a methanol solution for recrystallization to obtain compound 2; (yield: 74.96%).

[0109] The obtained compound 2 was tested and analyzed, and the results were as follows:

[0110] HPLC purity: >99.95%.

[0111] MS (ESI, m / Z): [M+H]+: 713.41.

[0112] Elemental Analysis:

[0113] Calculated values: C, 90.85; H, 4.94; N, 1.96; O, 2.24.

[0114] The test values ​​are: C, 90.21; H, 5.34; N, 2.32; O, 2.36.

[0115] Example 3

[0116]

[0117] After raw material A (1.0 eq, CAS: 125404-00-4) and raw material B (1.0 eq, CAS: 204530-94-9) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under N2 atmosphere, the temperature was raised to 115°C and stirred for reaction for 12 h. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (yield: 79.26%);

[0118] After the intermediate 1 (1.0 eq) and the raw material C (1.0 eq, CAS: 108313-41-3) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under a N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 8 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in the intermediate 2 (yield: 75.34%).

[0119] Under N2 protection, intermediate 2 (1.0 eq), raw material D (1.0 eq, CAS: 1256544-74-7), tetrakis(triphenylphosphine)palladium (0.01 eq) and potassium carbonate (2.0 eq) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, it was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake was dried and placed in a methanol solution for recrystallization to obtain compound 4; (yield: 81.57%).

[0120] The obtained compound 4 was tested and analyzed, and the results were as follows:

[0121] HPLC purity: >99.95%.

[0122] MS (ESI, m / Z): [M+H]+: 713.40.

[0123] Elemental Analysis:

[0124] Calculated values: C, 90.85; H, 4.94; N, 1.96; O, 2.24.

[0125] The test values ​​are: C, 90.01; H, 5.29; N, 2.22; O, 2.41.

[0126] Example 4

[0127]

[0128] After raw material A (1.0 eq, CAS: 125404-00-4) and raw material B (1.0 eq, CAS: 204530-94-9) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under N2 atmosphere, the temperature was raised to 115°C and stirred for reaction for 12 h. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (yield: 80.29%);

[0129] After the intermediate 1 (1.0 eq) and the raw material C (1.0 eq, CAS: 108313-41-3) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under a N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 8 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed using a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in the intermediate 2 (yield: 76.49%).

[0130] Under N2 protection, intermediate 2 (1.0 eq), raw material D (1.0 eq, CAS: 1627917-17-2), tetrakis(triphenylphosphine)palladium (0.01 eq) and potassium carbonate (2.0 eq) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, it was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake was dried and placed in a methanol solution for recrystallization to obtain compound 5; (yield: 78.11%).

[0131] The obtained compound 5 was tested and analyzed, and the results were as follows:

[0132] HPLC purity: >99.95%.

[0133] MS (ESI, m / Z): [M+H]+: 713.45.

[0134] Elemental Analysis:

[0135] Calculated values: C, 90.85; H, 4.94; N, 1.96; O, 2.24.

[0136] The test values ​​are: C, 90.25; H, 5.24; N, 2.22; O, 2.41.

[0137] Example 5

[0138]

[0139] After raw material A (1.0 eq, CAS: 125404-00-4) and raw material B (1.0 eq, CAS: 204530-94-9) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under N2 atmosphere, the temperature was raised to 115°C and stirred for reaction for 12 h. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:16) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in Intermediate 1 (yield: 79.88%);

[0140] After the intermediate 1 (1.0 eq) and the raw material C (1.0 eq, CAS: 108313-41-3) were dissolved in toluene, Pd2(dba)3 (0.01 eq), P(t-Bu)3 (0.5 eq) and t-BuONa (2.0 eq) were added under a N2 atmosphere, the temperature was raised to 115°C and the reaction was stirred for 8 hours. After the reaction was completed, diatomaceous earth was used for hot filtration to remove salt and catalyst. After the filtrate was cooled to room temperature, distilled water was added to the filtrate for washing. After separation, the organic phase was retained, the aqueous phase was extracted with ethyl acetate, and then the combined organic layer was dried with magnesium sulfate, and the solvent was removed with a rotary evaporator. Finally, a mixture of dichloromethane and petroleum ether (V:V=1:8) was used as an eluent, and the remaining substance was purified by column chromatography to obtain the compound shown in the intermediate 2 (yield: 75.92%).

[0141] Under N2 protection, intermediate 2 (1.0 eq), raw material D (1.0 eq, CAS: 2261008-20-0), tetrakis(triphenylphosphine)palladium (0.01 eq) and potassium carbonate (2.0 eq) were respectively added to a mixed solvent of toluene, ethanol and water, and the temperature was raised to 100°C for reaction for 10 h. After the reaction was completed, it was cooled to room temperature. After the solid was precipitated, it was filtered and washed with water to remove the salt, and then rinsed with a small amount of ethanol. The filter cake was dried and placed in a methanol solution for recrystallization to obtain compound 6; (yield: 76.47%).

[0142] The obtained compound 6 was tested and analyzed, and the results were as follows:

[0143] HPLC purity: >99.95%.

[0144] MS (ESI, m / Z): [M+H]+: 713.39.

[0145] Elemental Analysis:

[0146] Calculated values: C, 90.85; H, 4.94; N, 1.96; O, 2.24.

[0147] The test values ​​are: C, 90.31; H, 5.30; N, 2.24; O, 2.37.

[0148] Example 6

[0149]

[0150] A flask containing raw material a (1.0 eq, CAS: 2409562-95-2), raw material b (1.0 eq, CAS: 2648147-42-4), Pd2(dba)3 (0.02 eq), P(t-Bu)3 (0.5 eq), NaOtBu (2.0 eq) and a toluene solution was heated to 120°C and stirred for 8 hours, the reaction solution was cooled to room temperature, and water and ethyl acetate were added to separate the liquid layer. The solvent was then distilled off under reduced pressure and purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 50% / 50% (volume / volume)) to obtain the compound shown in Intermediate 1. (Yield: 64.35%).

[0151] A flask containing intermediate 1 (1.0 eq), raw material c (1.0 eq, CAS: 3034693-54-1), Pd2(dba)3 (0.02 eq), P(t-Bu)3 (0.5 eq), NaOtBu (2.0 eq) and toluene solution was heated to 120°C and stirred for 8 hours. The reaction solution was cooled to room temperature, and water and ethyl acetate were added to separate the liquid layer. The solvent was then distilled off under reduced pressure and purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 50% / 50% (volume / volume)) to obtain the compound shown in intermediate 2 (yield: 59.87%).

[0152] Tert-butyl lithium pentane solution (5.0eq) was added to a flask containing intermediate 2 (1.0eq) and tert-butylbenzene solution at -40 ° C under a nitrogen atmosphere. After completion of the dropwise addition, the temperature was raised to 70 ° C, and the mixture was stirred for 1 hour, and pentane was distilled off. After cooling to -40 ° C, boron tribromide (3.0eq) was added thereto, and the mixture was raised to room temperature and stirred for 1 hour. Thereafter, the mixture was cooled to 0 ° C again, and N, N-diisopropylethylamine (3.0eq) was added thereto and stirred at room temperature, and then stirred at 100 ° C for 3 hours. The reaction solution was cooled to 0 ° C, and potassium acetate saturated solution and ethyl acetate were added thereto to separate the liquid layer. The solvent was then distilled off under reduced pressure. It was purified by silica gel column chromatography (developing solvent: hexane / dichloromethane=40 / 1 (volume / volume)) to obtain compound BD-1. (yield: 42.8%).

[0153] The obtained compound BD-1 was tested and analyzed, and the results were as follows:

[0154] HPLC purity: >99.95%.

[0155] MS (ESI, m / Z): [M+H]+: 999.66.

[0156] Elemental Analysis:

[0157] Calculated values ​​are: C, 84.06; H, 7.46; N, 4.20; S, 3.21; B, 1.08.

[0158] The test values ​​are: C, 83.66; H, 7.69; N, 4.35; S, 3.25; B, 1.18.

[0159] Example 7

[0160]

[0161] A flask containing raw material a (1.0 eq, CAS: 2409562-95-2), raw material b (1.0 eq, CAS: 2648147-42-4), Pd2(dba)3 (0.02 eq), P(t-Bu)3 (0.5 eq), NaOtBu (2.0 eq) and toluene solution was heated to 120°C and stirred for 8 hours, the reaction solution was cooled to room temperature, and water and ethyl acetate were added to separate the liquid layer. The solvent was then distilled off under reduced pressure and purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 50% / 50% (volume / volume)) to obtain the compound shown in Intermediate 1; (yield: 67.51%).

[0162] A flask containing intermediate 1 (1.0 eq), raw material c (1.0 eq, CAS: 2262575-20-0), Pd2(dba)3 (0.02 eq), P(t-Bu)3 (0.5 eq), NaOtBu (2.0 eq) and toluene solution was heated to 120°C and stirred for 8 hours. The reaction solution was cooled to room temperature, and water and ethyl acetate were added to separate the liquid layer. The solvent was then distilled off under reduced pressure and purified by silica gel column chromatography (developing solvent: hexane / ethyl acetate = 50% / 50% (volume / volume)) to obtain the compound shown in intermediate 2; (yield: 52.31%).

[0163] Tert-butyl lithium pentane solution (5.0 eq) was added to a flask containing intermediate 2 (1.0 eq) and tert-butylbenzene solution at -40 ° C under a nitrogen atmosphere. After the dropwise addition was completed, the temperature was raised to 70 ° C, and the mixture was stirred for 1 hour, and pentane was distilled off. After cooling to -40 ° C, boron tribromide (3.0 eq) was added thereto, and the mixture was raised to room temperature and stirred for 1 hour. Thereafter, the mixture was cooled to 0 ° C again, and N, N-diisopropylethylamine (3.0 eq) was added thereto and stirred at room temperature, and then stirred at 100 ° C for 3 hours. The reaction solution was cooled to 0 ° C, and potassium acetate saturated solution and ethyl acetate were added thereto to separate the liquid layer. The solvent was then distilled off under reduced pressure. It was purified by silica gel column chromatography (developing solvent: hexane / dichloromethane=40 / 1 (volume / volume)) to obtain compound BD-37; (yield: 41.96%).

[0164] The obtained compound BD-37 was tested and analyzed, and the results are as follows:

[0165] HPLC purity: >99.95%.

[0166] MS (ESI, m / Z): [M+H]+: 944.88.

[0167] Elemental Analysis:

[0168] Calculated values ​​are: C, 83.86; H, 8.64; N, 2.96; S, 3.39; B, 1.14.

[0169] The test values ​​are: C, 83.43; H, 8.89; N, 3.21; S, 3.43; B, 1.20.

[0170] The synthesis method of the compound of formula I is the same as that in the above embodiment and will not be described in detail here. The mass spectra, molecular formulas and yields of other synthesis examples are shown in Table 1 below.

[0171] Table 1

[0172] Compound Molecular formula Mass spectrometry calculated value Mass spectrometry test value Yield (%) Compound 3 C54H35NO 713.27 713.35 65.98 Compound 8 C54H35NO 713.27 713.36 74.94 Compound 9 C54H35NO 713.27 713.4 70.68 Compound 10 C46H31NO 613.24 613.41 66.78 Compound 14 C50H33NO 663.26 663.45 77.74 Compound 18 C46H31NO 613.24 613.46 66.58 Compound 21 C54H35NO 713.27 713.36 70.55 Compound 25 C52H34N2O 702.27 702.45 68.88 Compound 33 C52H34N2O 702.27 702.37 73.06 Compound 37 C54H35NS 729.25 729.44 67.07 Compound 41 C54H35NS 729.25 729.39 69.28 Compound 47 C46H31NS 629.22 629.47 66.49 Compound 54 C46H31NS 629.22 629.39 68.02 Compound 59 C48H29NS2 683.17 683.34 72.7 Compound 64 C55H38N2S 758.28 758.45 77.37 Compound 72 C55H38N2S 758.28 758.38 71.1 Compound 78 C58H38N2S 794.28 794.35 77.71 Compound 82 C58H38N2O 778.30 778.57 69.82

[0173] The synthesis method of the compound of formula II is the same as that in the above embodiment, which is not described in detail here. The mass spectra, molecular formulas and yields of other synthesis examples are shown in Table 2 below.

[0174] Table 2

[0175]

[0176] [Application Example 1] Preparation of organic electroluminescent devices:

[0177] a. ITO anode: Wash the ITO (indium tin oxide)-Ag-ITO (indium tin oxide) glass substrate with a coating thickness of 150nm in distilled water twice, ultrasonically wash for 30 minutes, and then repeatedly wash it with distilled water twice, ultrasonically wash for 10 minutes. After washing, bake it in a vacuum oven at 220℃ for 2 hours. After baking, cool it down and it can be used. Use this substrate as the anode, use an evaporation machine to perform the evaporation device process, and evaporate other functional layers on it in sequence.

[0178] b. HIL (hole injection layer): The hole injection layer materials HT1-8 and P-9 are vacuum evaporated at a deposition rate of 97:3, and the thickness is 10 nm;

[0179] c. HTL (hole transport layer): At a deposition rate of 100%, 130 nm of HT1-8 was vacuum-deposited on the hole injection layer as a hole transport layer.

[0180] d. Prime (second hole transport layer): Vacuum evaporate 5 nm of the compound of formula I on the hole transport layer as a second hole transport layer at a deposition rate of ;

[0181] e. EML (light-emitting layer): Then on the second hole transport layer, The evaporation rate is 25 nm, and the BH-9 main material and the dopant material (Dopant) of formula II are vacuum evaporated to a thickness of 25 nm as the light-emitting layer, wherein the evaporation rate ratio of the main material to the dopant material (Dopant) of formula II is 97:3.

[0182] f. HB (hole blocking layer): The evaporation rate was 5.0 nm, and ET-7 was vacuum evaporated to a thickness of 5.0 nm as a hole blocking layer.

[0183] g. ETL (Electron Transport Layer): The evaporation rate of ET-14 and Liq was vacuum evaporated to a thickness of 30 nm as an electron transport layer, wherein the evaporation rate ratio of ET to Liq was 50:50.

[0184] h. EIL (electron injection layer): At a evaporation rate of , a 1.0 nm Yb film layer was evaporated to form an electron injection layer.

[0185] i. Cathode: The evaporation rate ratio is 1:9, and magnesium and silver are evaporated at 13nm, and the evaporation rate ratio is 1:9 to obtain an OLED device.

[0186] j. Light extraction layer: At a deposition rate of , CPL with a thickness of 70 nm was vacuum-deposited on the cathode as a light extraction layer.

[0187] k. Package the substrate after evaporation. First, use the glue coating equipment to coat the cleaned cover with UV glue, then move the coated cover to the pressing section, place the evaporation-deposited substrate on the upper end of the cover, and finally bond the substrate and cover with the bonding equipment, and complete the light curing of the UV glue.

[0188] The compounds used in the device are as follows:

[0189]

[0190] Device comparison ratio:

[0191] The device comparative example provides an organic electroluminescent device. The only difference between the preparation method of the organic electroluminescent device and the device embodiment 1 is that the organic electroluminescent device uses an existing comparative compound to replace the second hole transport layer or the doping material in the device embodiment 1 for evaporation to prepare the device comparative example, wherein the chemical structure of the comparative compound involved in the present invention is as follows:

[0192]

[0193] The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained from the device application examples 1-23 and the device comparative examples 1-19 were characterized at a brightness of 1000 (nits). The test results are shown in Table 3 below:

[0194] 1. Comparative Examples 1-4, Application Examples 1-9

[0195] The organic electroluminescent devices of Comparative Examples 1-4 and Application Examples 1-9 were prepared according to the above-mentioned method for preparing an organic electroluminescent device, BD-1 was used as a doping material, and the second hole transport material was selected from the compounds shown in Table 3.

[0196] 2. Comparative Examples 5-8, Application Examples 10-19

[0197] The organic electroluminescent devices of Comparative Examples 5-8 and Application Examples 10-19 were prepared according to the above-mentioned method for preparing an organic electroluminescent device, BD-37 was used as a doping material, and the second hole transport material was selected from the compounds shown in Table 3.

[0198] 3. Comparative Examples 9-12, Application Examples 20-23

[0199] The organic electroluminescent devices of Comparative Examples 9-12 and Application Examples 20-23 were prepared according to the above-mentioned method for preparing an organic electroluminescent device, BD-38 was used as a doping material, and the second hole transport material was selected from the compounds shown in Table 3.

[0200] 4. Comparative Examples 13-19

[0201] The organic electroluminescent devices of Comparative Examples 13-19 were prepared according to the above-mentioned method for preparing an organic electroluminescent device. The doping material and the second hole transport material were selected from the corresponding compounds in Table 3.

[0202] The performance of the organic electroluminescent devices of the comparative example and the application example was measured, and the measurement results are shown in Table 3.

[0203] Table 3: Luminous characteristics test results (brightness value is 1000nits)

[0204]

[0205]

[0206] Specifically, when BD-1 is used as the doping material, the overall driving voltage of the organic electroluminescent device of the present invention is 3.43-3.58V, the BI value is 190.1-203.9, and the life span is 489-513h; while the driving voltage of Comparative Examples 1 to 4 is 3.63-3.70V, the BI is 178.6-186.3, and the life span is 460-473h. When BD-37 and BD-38 are used as doping materials, the overall driving voltage is 3.54-3.68V, the BI value is 178.4-185.9, and the life span is 500-525h; while the driving voltage of Comparative Examples 5 to 12 is 3.69-3.75V, the BI is 170.5-175.5, and the life span is 483-491h. The driving voltage of Comparative Examples 13 to 19 prepared by the corresponding Compound 1, Compound 2, Compound 4, Compound 5, Compound 47, Compound 59, and Compound 82 is 3.69-3.75V, BI is 158.4-162.5, and life is 358-378h; it can be seen that the performance of the blue light organic electroluminescent device prepared by combining the second hole transport material of Formula I and the doping material of Formula II of the present invention is much higher than that of the comparative example.

[0207] The applicant declares that the present invention illustrates the organic electroluminescent device and its application through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises a first electrode, a second electrode facing the first electrode, a light-emitting layer between the first electrode and the second electrode, and a hole transport region between the first electrode and the light-emitting layer; The hole transport region comprises a compound shown in Formula I; In formula I, X is O or S; Ar is selected from any one of phenyl, biphenyl, terphenyl, naphthyl, anthracenyl and phenanthryl, and Ar is fused with the adjacent benzene ring on the parent nucleus, and the fusion position is 1,2, 2,3 or 3,4 of the benzene ring; L is selected from a connecting bond or When L is a connecting bond, the N atom is directly connected to the benzene ring; R3 is selected from any one of substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur; R1 is selected from any one of hydrogen, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted 3-30-membered heterocycloalkyl, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur; Ar1 and Ar2 are each independently selected from any one of a substituted or unsubstituted 3-30-membered heterocycloalkyl, a substituted or unsubstituted C6-C30 aryl, and a substituted or unsubstituted 3-30-membered heteroaryl, and the heteroatoms in the heterocycloalkyl and heteroaryl are independently selected from oxygen, nitrogen or sulfur; The doping material in the light-emitting layer is a compound shown in Formula II: In formula II, R4 is selected from substituted or unsubstituted diarylamine, substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl; R a -R d The same as or different from each other, and each independently selected from substituted or unsubstituted C1-C30 alkyl, substituted or unsubstituted C6-C30 aryl; R4, R a -R d Each independently represents a monosubstituted, disubstituted, trisubstituted, tetrasubstituted, pentasubstituted or unsubstituted group; The substituents in the substituted groups in Formula I and Formula II are selected from any one or a combination of at least two of deuterium, C1-C30 alkyl or C6-C30 aryl.

2. The organic electroluminescent device according to claim 1, characterized in that: L is selected from a connecting bond or any one of the following groups: * represents the attachment site of the group.

3. The organic electroluminescent device according to claim 1, characterized in that: R1 is independently selected from hydrogen or any one of the following groups: * represents the attachment site of the group.

4. The organic electroluminescent device according to claim 1, characterized in that: Ar1 and Ar2 are the same or different and are independently selected from one or a combination of several of the following groups: * represents the attachment site of the group.

5. The organic electroluminescent device according to claim 1, characterized in that: When R4 is selected from diarylamine, Formula II is selected from the following Formula II-1, R a When selected from substituted or unsubstituted C6-C30 aryl, Formula II is selected from the following Formula II-2:

6. The organic electroluminescent device according to claim 1, characterized in that: The compound represented by formula I is any one of the following compounds:

7. The organic electroluminescent device according to claim 1, characterized in that: The compound represented by formula II is any one of the following compounds:

8. The organic electroluminescent device according to claim 1, characterized in that: The hole transport region at least includes a hole injection layer, a first hole transport layer, and a second hole transport layer, and the second hole transport layer is a compound shown in Formula I.

9. A display panel, characterized in that: The display panel comprises the organic electroluminescent device according to any one of claims 1 to 8.

10. Use of the organic electroluminescent device according to any one of claims 1 to 8 in an organic light-emitting device, an organic solar cell, an electronic paper, an organic photoreceptor or an organic thin film transistor.

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