JP2017155033A - Quinoxaline compound and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quinoxaline compound suitable for a light emitting material of an organic EL element.SOLUTION: The present invention provides a quinoxaline compound represented by general formula (1) (Rand Rindependently represent a C6-20 aromatic hydrocarbon group or a C3-20 hetero aromatic group substituted/unsubstituted with a methyl group, an ethyl group, a C3-18 linear/branched/cyclic alkyl group, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group or a cyano group; R-Rindependently represent H, a methyl group, a phenyl group, a naphthyl group or a biphenyl group; Z is a substituent having a carbazole skeleton).SELECTED DRAWING: None

Description

  The present invention relates to a quinoxaline compound and an organic EL device using the same.

  An organic EL element is a surface-emitting element in which an organic thin film is held between a pair of electrodes, and has features such as a thin and light weight, a high viewing angle, and a high-speed response, and is expected to be applied to various display elements. . Recently, some practical applications such as mobile phone displays have begun. On the other hand, there is still a problem with the light emission efficiency of the organic EL element, and in particular, a light emitting material (light emission host, light emission dopant) having a large influence on the light emission efficiency is required to be improved.

  Light emission of the organic EL element is obtained by recombination of electrons and holes injected from the cathode and the anode inside the light emitting layer. Therefore, the material used for the light-emitting layer needs to have a bipolar property capable of receiving both electrons and holes. For example, in an organic EL element using a light emitting layer that cannot transport electrons and holes in a well-balanced manner, extra holes or electrons that do not contribute to light emission are generated, resulting in a decrease in light emission efficiency. Moreover, since excessive holes and electrons induce deterioration of the hole transport layer and the electron transport layer adjacent to the light emitting layer, the lifetime of the organic EL element is deteriorated.

  As the light-emitting host material, carbazole compounds such as 4,4′-bis (9-carbazolyl) biphenyl and 1,3-bis (9-carbazolyl) benzene are well known (for example, see Non-Patent Documents 1 and 2). ). However, these carbazole compounds are insufficient in terms of the bipolar property of transporting electrons and holes in a well-balanced manner, and satisfactory results are not obtained with respect to the light emission efficiency and lifetime of the organic EL element.

  Under such circumstances, light-emitting host materials in which a quinoxaline ring and a carbazole ring are combined have been reported (for example, see Patent Documents 1 to 5). In these compounds, the 2-position and / or 3-position of the quinoxaline ring is substituted with a carbazole ring or a substituent having a carbazole ring, and has bipolar properties. However, the light emitting host material of the organic EL element has room for improvement in terms of driving voltage, light emission efficiency, and life.

Applied Physics Letters, 1999, 75, 4 Applied Physics Letters, 2003, 82, 2422.

JP 2007-284434 A JP 2008-106051 A JP 2008-106062 A Korean Patent Application Publication No. 10-2014-0071944 Korean Patent Application Publication No. 10-2015-0071624

  An object of this invention is to provide the quinoxaline compound which improves the drive voltage, luminous efficiency, and lifetime of an organic EL element compared with a conventionally well-known material. Another object of the present invention is to provide an organic EL device having a low voltage, high luminous efficiency, and long life using the specific quinoxaline compound.

  As a result of intensive studies, the present inventors have found a quinoxaline compound represented by the following general formula (1) and have completed the present invention. The quinoxaline compound has a substituent in which a carbazole skeleton is essential at a specific position of the quinoxaline ring, and has not been reported or suggested in the prior art.

(Where
R ¹ and R ² are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these groups are each independently a methyl group, ethyl group, A substituent selected from the group consisting of a group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a cyano group, and a deuterium atom. One or more types], a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a cyano group, a deuterium atom, or a hydrogen atom.
R ^{3 to} R ⁵ each independently represent a hydrogen atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group.
Z is a substituent represented by any one of the following general formulas (2) to (21). )

(In the formula, R ⁶ , R ⁷ , R ⁹ , R ¹⁰ , R ^{12 to} R ³⁸ , R ^{40 to} R ⁴³ , R ^{45 to} R ⁴⁸ , R ^{50 to} R ⁵³ , and R ^{55 to} R ⁶⁶ are independent of each other. And represents a hydrogen atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group.
R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these Each independently represents a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a quinolyl group, Having at least one substituent selected from the group consisting of a pyrimidyl group, a diphenylpyridyl group, a diphenylpyrimidyl group, a diphenyltriazyl group, a dibenzothienyl group, a dibenzofuranyl group, a cyano group, and a deuterium atom; May also be expressed.
Ar ^{1 to} Ar ⁶ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these groups are each independently a methyl group, ethyl group, A substituent selected from the group consisting of a group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a dibenzofuranyl group, a dibenzothienyl group, a 9-carbazolyl group, a cyano group, and a deuterium atom It may have one or more groups].
X represents a single bond, an oxygen atom or a sulfur atom. )
That is, this invention relates to the quinoxaline compound represented by the said General formula (1), and its use.

  Although the quinoxaline compound of the present invention has a chemical structure that has not been reported or suggested by the prior art, it has a bipolar property capable of receiving electrons and holes. Therefore, the organic EL device having at least one light emitting layer containing the quinoxaline compound of the present invention can perform both electron injection and hole injection into the light emitting layer, and recombine electrons and holes in the light emitting layer. It is suggested that it can bear.

  As a result of further investigation, the quinoxaline compound of the present invention has a significantly lower driving voltage of the organic EL device than the inventive compound disclosed in the prior art based on the structural requirements different from the prior art, and emits light. There was a remarkable effect that the efficiency was remarkably improved and the device life was remarkably improved. Such a remarkable effect of the present invention cannot be easily predicted from the prior art having different constituent requirements.

  Therefore, according to the present invention, it is possible to provide an organic EL element having high luminance and efficiency and excellent lifetime.

  Hereinafter, the present invention will be described in detail.

In the quinoxaline compound represented by the general formula (1), R ¹ and R ² are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [ These groups are each independently a methyl group, an ethyl group, a C3-C18 linear, branched, or cyclic alkyl group, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a cyano group. And may have one or more substituents selected from the group consisting of deuterium atoms], a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a cyano group Represents a deuterium atom or a hydrogen atom.

The aromatic hydrocarbon group having 6 to 20 carbon atoms in R ¹ and R ² can be rephrased as an aromatic hydrocarbon group having 6 to 20 carbon atoms which may be linked or condensed, and as the substituent, Is not particularly limited, for example, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a benzofluorenyl group, a phenanthryl group, a fluoranthenyl group, an anthryl group, or a pyrenyl group. Can be mentioned.

The heteroaromatic group having 3 to 20 carbon atoms in R ¹ and R ² can be called a heteroaromatic group having 3 to 20 carbon atoms which may be linked or condensed, and as the substituent, Although it does not specifically limit, For example, the C3-C20 heteroaromatic group containing an at least 1 oxygen atom, a nitrogen atom, or a sulfur atom can be mentioned, More preferably, an oxygen atom, a nitrogen atom And a heteroaromatic group having 3 to 20 carbon atoms which contains at least one atom selected from the group consisting of sulfur atoms on the aromatic ring, and these groups are not particularly limited. For example, pyrrolyl group, thienyl group, furyl group, imidazolyl group, pyrazolyl group, thiazolyl group, isothiazolyl group, oxazolyl group, isoxazolyl group, pyridyl group, pyrimidide Group, pyrazyl group, 1,3,5-triazyl group, indolyl group, benzothienyl group, benzofuranyl group, benzoimidazolyl group, indazolyl group, benzothiazolyl group, benzoisothiazolyl group, 2,1,3-benzothiadiazolyl group Benzoxazolyl group, benzoisoxazolyl group, 2,1,3-benzoxiadiazolyl group, quinolyl group, isoquinolyl group, quinoxalyl group, quinazolyl group, carbazolyl group, dibenzothienyl group, dibenzofuranyl group, Examples include a phenoxazinyl group, a phenothiazinyl group, a phenazine group, and a thiantenyl group.

Although it does not specifically limit as a C3-C18 linear, branched or cyclic alkyl group in R < ¹ > and R < ² >, For example, a propyl group, an isopropyl group, n-butyl group, sec-butyl group Tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, stearyl group, cyclopropyl group, cyclohexyl group and the like.

Specific examples of R ¹ and R ² include phenyl group, 4-methylphenyl group, 3-methylphenyl group, 2-methylphenyl group, 4-ethylphenyl group, 3-ethylphenyl group, 2-ethylphenyl group, 4-n-propylphenyl group, 4-isopropylphenyl group, 2-isopropylphenyl group, 4-n-butylphenyl group, 4-isobutylphenyl group, 4-sec-butylphenyl group, 4-tert-butylphenyl group, 4-n-pentylphenyl group, 4-isopentylphenyl group, 4-neopentylphenyl group, 4-n-hexylphenyl group, 4-n-octylphenyl group, 4-n-decylphenyl group, 4-n- Dodecylphenyl group, 4-cyclopentylphenyl group, 4-cyclohexylphenyl group, 4-tritylphenyl group, 3-tritylphenyl Nyl group, 2,4-dimethylphenyl group, 2,5-dimethylphenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,6-dimethylphenyl group, 2,3,5-trimethyl Phenyl group, 2,3,6-trimethylphenyl group, 3,4,5-trimethylphenyl group, 4-cyanophenyl group, 3-cyanophenyl group, 3-cyanophenyl group, 4-biphenyl group, 3-biphenyl group 2-biphenyl group, 2-methyl-1,1′-biphenyl-4-yl group, 3-methyl-1,1′-biphenyl-4-yl group, 2′-methyl-1,1′-biphenyl- 4-yl group, 3′-methyl-1,1′-biphenyl-4-yl group, 4′-methyl-1,1′-biphenyl-4-yl group, 2,6-dimethyl-1,1′- Biphenyl-4-yl group, 2,2′-dimethyl- , 1′-biphenyl-4-yl group, 2,3′-dimethyl-1,1′-biphenyl-4-yl group, 2,4′-dimethyl-1,1′-biphenyl-4-yl group, 3 , 2′-dimethyl-1,1′-biphenyl-4-yl group, 2 ′, 3′-dimethyl-1,1′-biphenyl-4-yl group, 2 ′, 4′-dimethyl-1,1 ′ -Biphenyl-4-yl group, 2 ', 5'-dimethyl-1,1'-biphenyl-4-yl group, 2', 6'-dimethyl-1,1'-biphenyl-4-yl group, 4- Phenylbiphenyl group, 2-phenylbiphenyl group, 1-naphthyl group, 2-naphthyl group, 2-methylnaphthalen-1-yl group, 4-methylnaphthalen-1-yl group, 6-methylnaphthalen-2-yl group, 4- (1-naphthyl) phenyl group, 4- (2-naphthyl) phenyl group, 3- (1-naphthyl) phenyl Nyl group, 3- (2-naphthyl) phenyl group, 3-methyl-4- (1-naphthyl) phenyl group, 3-methyl-4- (2-naphthyl) phenyl group, 4- (2-methylnaphthalene-1) -Yl) phenyl group, 3- (2-methylnaphthalen-1-yl) phenyl group, 4-phenylnaphthalen-1-yl group, 4- (2-methylphenyl) naphthalen-1-yl group, 4- (3 -Methylphenyl) naphthalen-1-yl group, 4- (4-methylphenyl) naphthalen-1-yl group, 6-phenylnaphthalen-2-yl group, 4- (2-methylphenyl) naphthalen-2-yl group 4- (3-methylphenyl) naphthalen-2-yl group, 4- (4-methylphenyl) naphthalen-2-yl group, 2-fluorenyl group, 9,9-dimethyl-2-fluorenyl group, 9,9 − Diethyl-2-fluorenyl group, 9,9-di-n-propyl-2-fluorenyl group, 9,9-di-n-octyl-2-fluorenyl group, 9,9-diphenyl-2-fluorenyl group, 9, 9′-spirobifluorenyl group, 9-phenanthryl group, 2-phenanthryl group, 4- (9-phenanthryl) phenyl group, 3- (9-phenanthryl) phenyl group, 11,11′-dimethylbenzo [a] Fluoren-9-yl group, 11,11′-dimethylbenzo [a] fluoren-3-yl group, 11,11′-dimethylbenzo [b] fluoren-9-yl group, 11,11′-dimethylbenzo [b Fluoren-3-yl group, 11,11′-dimethylbenzo [c] fluoren-9-yl group, 11,11′-dimethylbenzo [c] fluoren-2-yl group, 3-fluora Nthenyl group, 8-fluoranthenyl group, 1-pyrenyl group, 2-pyrenyl group, 2-anthryl group, 9-anthryl group, 4- (9-anthryl) phenyl group, 4- (10-phenylanthracene-9- Yl) phenyl group, 1-imidazolyl group, 2-phenyl-1-imidazolyl group, 2-phenyl-3,4-dimethyl-1-imidazolyl group, 2,3,4-triphenyl-1-imidazolyl group, 2- (2-naphthyl) -3,4-dimethyl-1-imidazolyl group, 2- (2-naphthyl) -3,4-diphenyl-1-imidazolyl group, 1-methyl-2-imidazolyl group, 1-ethyl-2 -Imidazolyl group, 1-phenyl-2-imidazolyl group, 1-methyl-4-phenyl-2-imidazolyl group, 1-methyl-4,5-dimethyl-2-imidazolyl group, 1- Til-4,5-diphenyl-2-imidazolyl group, 1-phenyl-4,5-dimethyl-2-imidazolyl group, 1-phenyl-4,5-diphenyl-2-imidazolyl group, 1-phenyl-4,5 -Dibiphenylyl-2-imidazolyl group, 1-methyl-3-pyrazolyl group, 1-phenyl-3-pyrazolyl group, 1-methyl-4-pyrazolyl group, 1-phenyl-4-pyrazolyl group, 1-methyl-5- Pyrazolyl group, 1-phenyl-5-pyrazolyl group, 2-thiazolyl group, 4-thiazolyl group, 5-thiazolyl group, 3-isothiazolyl group, 4-isothiazolyl group, 5-isothiazolyl group, 2-oxazolyl group, 4-oxazolyl group Group, 5-oxazolyl group, 3-isoxazolyl group, 4-isoxazolyl group, 5-isoxazolyl group, 2-pyridyl group, -Methyl-2-pyridyl group, 4-methyl-2-pyridyl group, 5-methyl-2-pyridyl group, 6-methyl-2-pyridyl group, 3-pyridyl group, 4-methyl-3-pyridyl group, 4 -Pyridyl group, 2-pyrimidyl group, 2,2'-bipyridin-3-yl group, 2,2'-bipyridin-4-yl group, 2,2'-bipyridin-5-yl group, 2,3'- Bipyridin-3-yl group, 2,3′-bipyridin-4-yl group, 2,3′-bipyridin-5-yl group, 5-pyrimidyl group, pyrazyl group, 1,3,5-triazyl group, 4, 6-diphenyl-1,3,5-triazin-2-yl group, 1-benzimidazolyl group, 2-methyl-1-benzoimidazolyl group, 2-phenyl-1-benzoimidazolyl group, 1-methyl-2-benzimidazolyl group, 1 -Phenyl-2-benzimi Dazolyl group, 1-methyl-5-benzimidazolyl group, 1,2-dimethyl-5-benzimidazolyl group, 1-methyl-2-phenyl-5-benzimidazolyl group, 1-phenyl-5-benzimidazolyl group, 1,2-diphenyl -5-benzimidazolyl group, 1-methyl-6-benzimidazolyl group, 1,2-dimethyl-6-benzimidazolyl group, 1-methyl-2-phenyl-6-benzimidazolyl group, 1-phenyl-6-benzimidazolyl group, 1, 2-diphenyl-6-benzimidazolyl group, 1-methyl-3-indazolyl group, 1-phenyl-3-indazolyl group, 2-benzothiazolyl group, 4-benzothiazolyl group, 5-benzothiazolyl group, 6-benzothiazolyl group, 7-benzothiazolyl group Group, 3-benzoisothiazolyl group, -Benzoisothiazolyl group, 5-benzoisothiazolyl group, 6-benzoisothiazolyl group, 7-benzisothiazolyl group, 2,1,3-benzothiadiazol-4-yl group, 2,1,3 -Benzothiadiazol-5-yl group, 2-benzoxazolyl group, 4-benzoxazolyl group, 5-benzoxazolyl group, 6-benzoxazolyl group, 7-benzoxazolyl group, 3 -Benzoisoxazolyl group, 4-benzisoxazolyl group, 5-benzisoxazolyl group, 6-benzisoxazolyl group, 7-benzisoxazolyl group, 2,1,3- Benzoxadiazolyl-4-yl group, 2,1,3-benzooxadiazolyl-5-yl group, 2-quinolyl group, 3-quinolyl group, 5-quinolyl group, 6-quinolyl group, 1-isoquinolyl group 4 Isoquinolyl group, 5-isoquinolyl group, 2-quinoxalyl group, 3-phenyl-2-quinoxalyl group, 6-quinoxalyl group, 2,3-dimethyl-6-quinoxalyl group, 2,3-diphenyl-6-quinoxalyl group, 2 -Quinazolyl group, 4-quinazolyl group, 2-acridinyl group, 9-acridinyl group, 1,10-phenanthroline-3-yl group, 1,10-phenanthroline-5-yl group, 2-thienyl group, 3-thienyl group 2-benzothienyl group, 3-benzothienyl group, 2-dibenzothienyl group, 4-dibenzothienyl group, 2-furanyl group, 3-furanyl group, 2-benzofuranyl group, 3-benzofuranyl group, 2-dibenzofuranyl group Group, 4-dibenzofuranyl group, 9-methylcarbazol-2-yl group, 9-methylcarbazol-3-yl group, 9 -Methylcarbazol-4-yl group, 9-phenylcarbazol-2-yl group, 9-phenylcarbazol-3-yl group, 9-phenylcarbazol-4-yl group, 9-biphenylcarbazol-2-yl group, 9 -Biphenylcarbazol-3-yl group, 9-biphenylcarbazol-4-yl group, 2-thianthryl group, 10-phenylphenothiazin-3-yl group, 10-phenylphenothiazin-2-yl group, 10-phenylphenoxazine- 3-yl group, 10-phenylphenoxazin-2-yl group, 1-methylindol-2-yl group, 1-phenylindol-2-yl group, 9-phenylcarbazol-4-yl group, 1-methylindole 2-yl group, 1-phenylindol-2-yl group, 4- (2-pyridyl) phenyl group, -(3-pyridyl) phenyl group, 4- (4-pyridyl) phenyl group, 3- (2-pyridyl) phenyl group, 3- (3-pyridyl) phenyl group, 3- (4-pyridyl) phenyl group, 4 -(2-phenylimidazol-1-yl) phenyl group, 4- (1-phenylimidazol-2-yl) phenyl group, 4- (2,3,4-triphenylimidazol-1-yl) phenyl group, 4 -(1-methyl-4,5-diphenylimidazol-2-yl) phenyl group, 4- (2-methylbenzimidazol-1-yl) phenyl group, 4- (2-phenylbenzimidazol-1-yl) phenyl Group, 4- (1-methylbenzimidazol-2-yl) phenyl group, 4- (2-phenylbenzimidazol-1-yl) phenyl group, 3- (2-methylbenzoy Dazol-1-yl) phenyl group, 3- (2-phenylbenzimidazol-1-yl) phenyl group, 3- (1-methylbenzimidazol-2-yl) phenyl group, 3- (2-phenylbenzimidazole- 1-yl) phenyl group, 4- (3,5-diphenyltriazin-1-yl) phenyl group, 4- (2-thienyl) phenyl group, 4- (2-furanyl) phenyl group, 5-phenylthiophene-2 -Yl group, 5-phenylfuran-2-yl group, 4- (5-phenylthiophen-2-yl) phenyl group, 4- (5-phenylfuran-2-yl) phenyl group, 3- (5-phenyl) Thiophen-2-yl) phenyl group, 3- (5-phenylfuran-2-yl) phenyl group, 4- (2-benzothienyl) phenyl group, 4- (3-benzothienyl) phenyl Enyl group, 3- (2-benzothienyl) phenyl group, 3- (3-benzothienyl) phenyl group, 4- (2-dibenzothienyl) phenyl group, 4- (4-dibenzothienyl) phenyl group, 3- ( 2-dibenzothienyl) phenyl group, 3- (4-dibenzothienyl) phenyl group, 4- (2-dibenzofuranyl) phenyl group, 4- (4-dibenzofuranyl) phenyl group, 3- (2-dibenzofuran) Nyl) phenyl group, 3- (4-dibenzofuranyl) phenyl group, 5-phenylpyridin-2-yl group, 4-phenylpyridin-2-yl group, 5-phenylpyridin-3-yl group, 4- ( 9-carbazolyl) phenyl group, 3- (9-carbazolyl) phenyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pliers Group, hexyl group, heptyl group, octyl group, stearyl group, cyclopropyl group, a cyclohexyl group, a cyano group, can be exemplified deuterium atom, or a hydrogen atom, etc., but is not limited thereto.

R ¹ and R ² are each independently an aromatic hydrocarbon group having 6 to 14 carbon atoms that may be linked or condensed, or at least, in that the effect of extending the lifetime of the organic EL device is high. A C3-C12 heteroaromatic group containing one oxygen atom, nitrogen atom, or sulfur atom [these groups are each independently a methyl group, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, And may have one or more substituents selected from the group consisting of a pyridyl group], preferably a methyl group or a hydrogen atom, each independently a phenyl group, a methylphenyl group, a naphthyl group, More preferably a biphenyl group, a terphenyl group, a phenanthryl group, a naphthylphenyl group, a phenanthrylphenyl group, a pyridyl group, a pyridylphenyl group, or a hydrogen atom. Preferred, each independently, a phenyl group, methylphenyl group, a naphthyl group, more preferably a biphenyl group, or a hydrogen atom.

  Although it does not specifically limit as said C6-C14 linked or condensed aromatic hydrocarbon group, For example, a phenyl group, a naphthyl group, a biphenyl group, or an anthryl group etc. are mentioned. It is done.

  The C3-C12 heteroaromatic group containing at least one oxygen atom, nitrogen atom, or sulfur atom is not particularly limited, but includes pyridyl group, phenylpyridyl group, pyridylphenyl group, dibenzo Examples include a furanyl group or a dibenzothienyl group.

R ^{3 to} R ⁵ each independently represent a hydrogen atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group. Among these, a hydrogen atom, a methyl group, or a phenyl group is preferable independently from the viewpoint that the effect of extending the lifetime of the organic EL element is high, and a hydrogen atom is more preferable.

  In the quinoxaline compound represented by the general formula (1), Z is represented by any one of the following general formulas (2) to (21).

In the general formulas (2) to (21), R ⁶ , R ⁷ , R ⁹ , R ¹⁰ , R ^{12 to} R ³⁸ , R ^{40 to} R ⁴³ , R ^{45 to} R ⁴⁸ , R ^{50 to} R ⁵³ , and R ^{55 to} R ⁶⁶ each independently represent a hydrogen atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group.

R ⁶ , R ⁷ , R ⁹ , R ¹⁰ , R ^{12 to} R ³⁸ , R ^{40 to} R ⁴³ , R ^{45 to} R ⁴⁸ , R ^{50 to} R ⁵³ , and R ^{55 to} R ⁶⁶ are long lifetimes of organic EL elements. It is preferable that they are each independently a hydrogen atom, a methyl group, or a phenyl group from the viewpoint of excellent conversion effect.

In the general formulas (2) to (21), R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms, or A heteroaromatic group having 3 to 20 carbon atoms [these groups are each independently a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a biphenyl group, From the group consisting of naphthyl group, phenanthryl group, pyridyl group, quinolyl group, pyrimidyl group, diphenylpyridyl group, diphenylpyrimidyl group, diphenyltriazyl group, dibenzothienyl group, dibenzofuranyl group, cyano group, and deuterium atom It may have one or more selected substituents].

In R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ , the aromatic hydrocarbon group having 6 to 20 carbon atoms has the same definition as that represented by R ¹ and R ² , and a preferred range Is the same as that shown for R ¹ and R ² .

In R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ , the heteroaromatic group having 3 to 20 carbon atoms has the same definition as that represented by R ¹ and R ² , and preferred ranges are as follows. Are the same as those shown for R ¹ and R ² .

In R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ , the linear, branched, or cyclic alkyl group having 3 to 18 carbon atoms has the same definition as that shown for R ¹ and R ^2. The preferred range is the same as that shown for R ¹ and R ² .

R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are aromatics that may be linked or condensed with 6 to 14 carbon atoms in that they are excellent in the effect of extending the lifetime of the organic EL device. A hydrocarbon group, or a C3-C12 heteroaromatic group containing at least one oxygen atom, nitrogen atom, or sulfur atom [these groups are each independently a methyl group, a phenyl group, a biphenyl group, , Naphthyl group, phenanthryl group, pyridyl group, quinolyl group, pyrimidyl group, diphenylpyridyl group, diphenylpyrimidyl group, diphenyltriazyl group, dibenzothienyl group, dibenzofuranyl group, cyano group, and deuterium atom It may preferably have one or more substituents selected from the above, and each independently represents a phenyl group, a naphthyl group, a fluorenyl group, a phenyl group, A tontyl group, a pyridyl group, a pyrimidyl group, a triazyl group, a quinolyl group, a quinazolyl group, a dibenzofuranyl group, or a dibenzothienyl group [these groups are each independently a methyl group, a phenyl group, a biphenyl group, a naphthyl group, Substitution selected from the group consisting of phenanthryl group, pyridyl group, quinolyl group, pyrimidyl group, diphenylpyridyl group, diphenylpyrimidyl group, diphenyltriazyl group, dibenzothienyl group, dibenzofuranyl group, cyano group, and deuterium atom May have one or more groups], and each independently represents a phenyl group, a methylphenyl group, a naphthyl group, a biphenyl group, a terphenyl group, a dimethylfluorenyl group, a phenanthryl group, a naphthylphenyl group, Phenanthrylphenyl group, pyridyl group, diphenylpyridyl group, di Phenylpyrimidyl group, diphenyltriazyl group, quinolyl group, quinazolyl group, phenylquinazolyl group, biphenylquinazolyl group, dibenzofuranyl group, dibenzothienyl group, pyridylphenyl group, diphenylpyrimidylphenyl group, diphenyl A triazylphenyl group, a dibenzofuranylphenyl group, or a dibenzothienylphenyl group is more preferable.

The above-mentioned aromatic hydrocarbon group having 6 to 14 carbon atoms which may be linked or condensed is the same definition as that represented by R ¹ and R ² , and the preferred range is also represented by R ¹ and R ² . It is the same as that.

The C3-C12 heteroaromatic group containing at least one oxygen atom, nitrogen atom, or sulfur atom has the same definition as that represented by R ¹ and R ² , and the preferred range is also R ^1. And R ² are the same.

In the general formulas (2) to (21), Ar ^{1 to} Ar ⁶ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these Each group is independently a methyl group, an ethyl group, a linear, branched, or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a dibenzofuranyl group, a dibenzothienyl group, a 9-carbazolyl group, or a cyano group. And may have one or more substituents selected from the group consisting of deuterium atoms].

In Ar ^{1 to} Ar ⁶ , the aromatic hydrocarbon group having 6 to 20 carbon atoms has the same definition as that represented by R ¹ and R ² , and the preferred range is the same as that represented by R ¹ and R ^2. It is.

In Ar ^{1 to} Ar ⁶ , the heteroaromatic group having 3 to 20 carbon atoms has the same definition as that represented by R ¹ and R ² , and the preferred range is the same as that represented by R ¹ and R ^2. is there.

In Ar ^{1 to} Ar ⁶ , the linear, branched, or cyclic alkyl group having 3 to 18 carbon atoms has the same definition as that represented by R ¹ and R ² , and the preferred range is also represented by R ¹ and R ² . It is the same as that shown.

Ar ^{1 to} Ar ⁶ are aromatic hydrocarbon groups having 6 to 14 carbon atoms which may be linked or condensed, or at least one oxygen atom or nitrogen atom, in terms of excellent longevity of the organic EL device. , Or a C3-C12 heteroaromatic group containing a sulfur atom [these groups are each independently a methyl group, an ethyl group, a C3-C18 linear, branched, or cyclic alkyl group , A phenyl group, a dibenzofuranyl group, a dibenzothienyl group, a 9-carbazolyl group, a cyano group, and a substituent selected from the group consisting of a deuterium atom may be preferable]. Independently, phenyl group, methylphenyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, naphthylphenyl group, dibenzofuranyl group, dibenzothienyl group, dibenzofuran More preferably, they are each a ruphenyl group or a dibenzothienylphenyl group [these groups may each independently have a methyl group or an ethyl group], and each independently a phenyl group or a methylphenyl group. More preferably a naphthyl group, a biphenyl group, a terphenyl group, a phenanthryl group, a naphthylphenyl group, a dibenzofuranyl group, a dibenzothienyl group, a dibenzofuranylphenyl group, or a dibenzothienylphenyl group, More preferably, it is a phenyl group, a methylphenyl group, a naphthyl group, or a biphenyl group.

The above-mentioned aromatic hydrocarbon group having 6 to 14 carbon atoms which may be linked or condensed is the same definition as that represented by R ¹ and R ² , and the preferred range is also represented by R ¹ and R ² . It is the same as that.

The C3-C12 heteroaromatic group containing at least one oxygen atom, nitrogen atom, or sulfur atom has the same definition as that represented by R ¹ and R ² , and the preferred range is also R ^1. And R ² are the same.

  In the general formulas (2) to (21), X represents a single bond, an oxygen atom or a sulfur atom.

  Although the preferable compound of this invention is illustrated below, it is not limited to these compounds.

  The quinoxaline compound represented by the general formula (1) can be synthesized, for example, by the following route. A halogenated quinoxaline compound (21) is obtained by a condensation reaction of halogenated orthophenylenediamines (19) and 1,2-diketones (20). Subsequently, the halogenated quinoxaline compound (21) and the secondary amine compound represented by the general formula (22) are reacted using a copper catalyst or a palladium catalyst in the presence of a base, according to the general formula (1). The quinoxaline compound represented can be obtained.

[Wherein R ^{1 to} R ⁵ and Z represent the same definition as in the general formula (1). A represents a halogen atom (iodine, bromine, chlorine, or fluorine). ]
As the compounds represented by the general formulas (19), (20) and (22), commercially available compounds can be used, or they can be synthesized based on generally known methods.

  The quinoxaline compound represented by the general formula (1) of the present invention can be preferably used as a light emitting host material, a light emitting dopant material, an electron transport material, and a hole transport material for an organic EL device. The quinoxaline compound represented by the general formula (1) of the present invention has bipolar properties, can stably transport holes and electrons, and further has excellent light emission characteristics. When used as a light emitting layer, it is possible to achieve high efficiency and long life of the organic EL element.

  When the quinoxaline compound represented by the general formula (1) of the present invention is used as a light emitting layer of an organic EL device, the quinoxaline compound is used alone, used by doping a known light emitting host material, or a known It can be used by doping with a luminescent dopant.

  For the light-emitting layer when the quinoxaline compound represented by the general formula (1) is used as a hole transport layer or an electron transport layer of an organic EL device, a conventionally known fluorescent or phosphorescent light-emitting material is used. can do. The light emitting layer may be formed of only one kind of light emitting material, or one or more kinds of light emitting materials may be doped in the host material.

  Examples of a method for forming a light emitting layer, a hole transport layer, or an electron transport layer containing the quinoxaline compound represented by the general formula (1) include known methods such as vacuum deposition, spin coating, and casting. Can be applied.

  As a basic structure of the organic EL device that can obtain the effects of the present invention, those including a substrate, an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and a cathode are preferable. Layers may be omitted, or vice versa.

  The anode and cathode of the organic EL element are connected to a power source through an electrical conductor. The organic EL element operates by applying a potential between the anode and the cathode.

  Holes are injected into the organic EL element from the anode, and electrons are injected into the organic EL element at the cathode.

  The organic EL element is typically placed on a substrate, and the anode or cathode can be in contact with the substrate. The electrode in contact with the substrate is called the lower electrode for convenience. Generally, the lower electrode is an anode, but the organic EL element of the present invention is not limited to such a form.

  The substrate may be light transmissive or opaque depending on the intended emission direction. The light transmission characteristics can be confirmed by electroluminescence emission through the substrate. Generally, transparent glass or plastic is used as the substrate in such a case. The substrate may be a composite structure including multiple material layers.

  When the electroluminescent emission is confirmed through the anode, the anode is formed by passing or substantially passing through the emission.

  The general transparent anode (anode) material used in the present invention is not particularly limited, and examples thereof include indium-tin oxide (ITO), indium-zinc oxide (IZO), and tin oxide. . Other metal oxides such as aluminum or indium doped tin oxide, magnesium-indium oxide, or nickel-tungsten oxide can also be used. In addition to these oxides, metal nitrides such as gallium nitride, metal selenides such as zinc selenide, or metal sulfides such as zinc sulfide can be used as the anode.

The anode can be modified with plasma deposited fluorocarbon. If electroluminescence emission is confirmed only through the cathode, the transmission properties of the anode are not critical and any conductive material that is transparent, opaque or reflective can be used. Examples of conductors for this application include gold, iridium, molybdenum, palladium, platinum and the like.

  A plurality of hole transporting layers such as a hole injection layer and a hole transport layer can be provided between the anode and the light emitting layer. The hole injection layer and the hole transport layer have a function of transmitting holes injected from the anode to the light emitting layer. By interposing these layers between the anode and the light emitting layer, the hole injection layer and the hole transport layer are often used in a lower electric field. Holes can be injected into the light emitting layer.

  In the organic EL device of the present invention, a known hole injection material and hole transport material can be used as the hole transport layer and / or the hole injection layer. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbenes Derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, particularly thiophene oligomers. As the hole injecting material and the hole transporting material, those described above can be used, and porphyrin compounds, aromatic tertiary amine compounds, and styrylamine compounds, particularly aromatic tertiary amine compounds can be used. preferable.

  Representative examples of the aromatic tertiary amine compound and styrylamine compound include N, N, N ′, N′-tetraphenyl-4,4′-diaminophenyl, N, N′-diphenyl-N, N ′. -Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD), 2,2-bis (4-di-p-tolylaminophenyl) propane, 1,1- Bis (4-di-p-tolylaminophenyl) cyclohexane, N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl, 1,1-bis (4-di-p- Tolylaminophenyl) -4-phenylcyclohexane, bis (4-dimethylamino-2-methylphenyl) phenylmethane, bis (4-di-p-tolylaminophenyl) phenylmethane, N, N′-diphenyl-N, N -Di (4-methoxyphenyl) -4,4'-diaminobiphenyl, N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether, 4,4'-bis (diphenylamino) quadri Phenyl, N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4 ′-[4- (di-p-tolylamino) styryl] stilbene, 4-N, N-diphenyl Amino- (2-diphenylvinyl) benzene, 3-methoxy-4′-N, N-diphenylaminostilbenzene, N-phenylcarbazole, 4,4′-bis [N- (1-naphthyl) -N-phenylamino ] Biphenyl (NPD), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA) and the like. That.

  In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material. The hole injection layer and the hole transport layer may have a single layer structure composed of one or more of the above materials, or may have a multilayer structure composed of a plurality of layers having the same composition or different compositions.

  In the organic EL device of the present invention, the light emitting layer contains the quinoxaline compound of the present invention. For the light emitting layer, a known light emitting material (light emitting host material, fluorescent dopant, phosphorescent dopant) can be selected and combined with the quinoxaline compound of the present invention.

  Examples of the light-emitting host material include compounds having a biphenyl group, a fluorenyl group, a triphenylsilyl group, a carbazole group, a pyrenyl group, or an anthranyl group. For example, DPVBi (4,4′-bis (2,2-diphenylvinyl) -1,1′-biphenyl), BCzVBi (4,4′-bis (9-ethyl-3-carbazovinylene) 1,1′-biphenyl ), TBADN (2-tert-butyl-9,10-di (2-naphthyl) anthracene), ADN (9,10-di (2-naphthyl) anthracene), CBP (4,4′-bis (carbazole-9) -Yl) biphenyl), CDBP (4,4′-bis (carbazol-9-yl) -2,2′-dimethylbiphenyl), 9,10-bis (biphenyl) anthracene and the like.

  Examples of fluorescent dopants include anthracene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compound, thiopyran compound, polymethine compound, pyrylium or thiapyrylium compound, fluorene derivative, perifanthene derivative, indenoperylene derivative, Examples thereof include bis (azinyl) amine boron compounds, bis (azinyl) methane compounds, and carbostyryl compounds.

  As an example of the phosphorescent dopant, an organometallic complex of a transition metal such as iridium, platinum, palladium, or osmium can be given.

Examples of dopants include Alq ₃ (tris (8-hydroxyquinoline) aluminum)), DPAVBi (4,4′-bis [4- (di-para-tolylamino) styryl] biphenyl), perylene, Ir (PPy) ₃ ( Examples include tris (2-phenylpyridine) iridium (III), FlrPic (bis (3,5-difluoro-2- (2-pyridyl) phenyl- (2-carboxypyridyl) iridium (III)), and the like.

  Examples of the electron transporting material include alkali metal complexes, alkaline earth metal complexes, and earth metal complexes. Examples of the alkali metal complex, alkaline earth metal complex, or earth metal complex include 8-hydroxyquinolinate lithium (Liq), bis (8-hydroxyquinolinato) zinc, and bis (8-hydroxyquinolinate). Copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, Bis (10-hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) ( o-cresolate) gallium, bis (2-methyl-8-quinolinate) 1-naphthyl Trat aluminum, bis (2-methyl-8-quinolinato) -2-naphthoquinone Trad gallium, and the like.

  A hole blocking layer may be provided between the light emitting layer and the electron transport layer for the purpose of improving carrier balance. Desirable compounds for the hole element layer are BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen (4,7-diphenyl-1,10-phenanthroline), BAlq (bis (2 -Methyl-8-quinolinolato) -4- (phenylphenolato) aluminum) or bis (10-hydroxybenzo [h] quinolinato) beryllium).

  In the organic EL device of the present invention, an electron injection layer may be provided for the purpose of improving electron injection properties and improving device characteristics (for example, light emission efficiency, constant voltage driving, or high durability).

Preferred compounds for the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane, anthrone, etc. Is mentioned. In addition, the above-described metal complexes, alkali metal oxides, alkaline earth oxides, rare earth oxides, alkali metal halides, alkaline earth halides, rare earth halides, SiO ₂ , AlO, SiN, SiON, AlON, Various oxides such as GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, and C, and inorganic compounds such as nitride and oxynitride can also be used.

If light emission is confirmed only through the anode, the cathode used in the present invention can be formed from any conductive material. Desirable cathode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, indium , Lithium / aluminum mixtures, rare earth metals and the like.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited by these Examples.

¹ H-NMR and ¹³ C-NMR measurements were performed using Gemini 200 manufactured by Varian.

  The FDMS measurement was performed using Hitachi M-80B.

  Synthesis Example 1 (Synthesis of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole)

  Under a nitrogen stream, in a 30 mL three-necked flask, 0.6 g (3.0 mmol) of 2-chlorocarbazole, 1.0 g (3.0 mmol) of 6-bromo-2,3-diphenylquinoxaline, 0.6 g of potassium carbonate (4. 5 mmol), 10 mL of o-xylene, 6 mg (0.03 mmol) of palladium acetate, and 20 mg (0.1 mmol) of tri (tert-butyl) phosphine were added and stirred at 130 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 1.2 g (2.5 mmol) of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole as a yellow powder was obtained. (Yield 85%).

The compound was identified by ¹ H-NMR measurement and ¹³ C-NMR measurement.

¹ H-NMR (CDCl ₃ ) δ (ppm); 8.36-8.39 (m, 2H), 8.02-8.11 (m, 2H), 7.94 (d, 1H), 7. 27-7.55 (m, 15H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.81, 154.32, 142.20, 141.30, 141.10, 140.53, 139.08, 139.02, 138.64, 132 36, 131.45, 130.17, 129.45, 129.38, 129.00, 128.67, 126.83, 126.21, 123.53, 122.70, 121.59, 121.44 , 121.38, 120.72, 110.27
Synthesis Example 2 (Synthesis of 4-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole)

  Under a nitrogen stream, in a 30 mL three-necked flask, 0.6 g (3.0 mmol) of 4-chlorocarbazole, 1.0 g (3.0 mmol) of 6-bromo-2,3-diphenylquinoxaline, 0.6 g of potassium carbonate (4. 5 mmol), 10 mL of o-xylene, 6 mg (0.03 mmol) of palladium acetate, and 20 mg (0.1 mmol) of tri (tert-butyl) phosphine were added and stirred at 130 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 1.1 g (2.4 mmol) of 4-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole as a yellow powder was obtained. Released (yield 81%).

The compound was identified by ¹ H-NMR measurement and ¹³ C-NMR measurement.

¹ H-NMR (CDCl ₃ ) δ (ppm); 8.70 (d, 1H), 8.35-8.38 (m, 2H), 7.92 (d, 1H), 7.28-7. 56 (m, 16H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.77, 154.35, 142.15, 141.95, 140.96, 140.59, 139.08, 139.02, 138.72, 131 .36, 130.17, 129.46, 129.40, 129.33, 129.28, 128.68, 127.07, 126.70, 123.62, 123.03, 121.74, 121.35 121.27, 109.89, 108.46.
Example 1 (Synthesis of Compound (D5))

  In a 30 mL three-necked flask under a nitrogen stream, 1.0 g (2.0 mmol) of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole obtained in Synthesis Example 1 and N, N-bis ( 4-biphenyl) amine 0.64 g (2.0 mmol), sodium-tert-butoxide 0.27 g (2.8 mmol), o-xylene 10 mL, palladium acetate 4 mg (0.02 mmol), and tri (tert-butyl) phosphine 14 mg (0.07 mmol) was added and stirred at 140 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 1.4 g (1.8 mmol) of a yellow powder of compound (D5) was isolated (yield 91%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 766 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.24-8.33 (m, 2H), 8.02-8.06 (m, 2H), 7.90 (d, 1H), 7. 13-7.54 (m, 33H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.63, 154.007, 147.54, 146.67, 142.25, 141.84, 141.33, 140.85, 140.43, 139 .15, 139.06, 135.44, 131.25, 130.14, 129.31, 129.26, 129.14, 129.06, 128.61, 128.08, 127.11, 126.91 , 126.08, 125.97, 124.20, 124.11, 121.58, 121.22, 120.38, 120.28, 119.55, 110.01, 106.74.
Example 2 (Synthesis of Compound (F5))

  In a 30 mL three-necked flask under a nitrogen stream, 1.0 g (2.0 mmol) of 4-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole obtained in Synthesis Example 2 and N, N-bis ( 4-biphenyl) amine 0.64 g (2.0 mmol), sodium-tert-butoxide 0.27 g (2.8 mmol), o-xylene 10 mL, palladium acetate 4 mg (0.02 mmol), and tri (tert-butyl) phosphine 14 mg (0.07 mmol) was added and stirred at 140 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 1.3 g (1.7 mmol) of a yellow powder of compound (F5) was isolated (yield 88%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 766 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.39-8.47 (m, 2H), 8.04 (d, 1H), 7.92 (d, 1H), 7.22-7. 56 (m, 32H), 7.06-7.16 (m, 2H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.72, 154.23, 146.96, 142.64, 142.25, 141.49, 140.97, 140.79, 140.52, 139 12, 139.08, 134.90, 131.23, 130.16, 129.52, 129.42, 129.35, 128.99, 128.67, 128.13, 127.53, 126.97. 126.88, 126.58, 126.44, 123.59, 122.33, 121.49, 121.22, 109.61, 107.88.
Example 3 (Synthesis of Compound (B4))

  In a 50 mL three-necked flask under a nitrogen stream, 2.8 g (7.8 mmol) of 6-bromo-2,3-diphenylquinoxaline, 3.0 g (8.2 mmol) of 9-biphenylcarbazole-2-boronic acid, tetrakis (triphenyl) Phosphine) palladium (0.27 g, 0.24 mmol), tetrahydrofuran (10 mL), and 20 wt% aqueous sodium carbonate solution (10 g) (19.6 mmol as sodium carbonate) were added, and the mixture was heated to reflux for 7 hours. After cooling to room temperature, the aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane) to isolate 4.2 g (7.0 mmol) of a pale yellow solid of compound (B4) (yield 89%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 599 (M +)
Example 4 (Synthesis of Compound (C18))

  In a 50 mL three-necked flask under a nitrogen stream, 5.1 g (10.0 mmol) of 6-bromo-2,3-dibiphenylquinoxaline, 3.0 g (10.5 mmol) of 9-phenylcarbazole-3-boronic acid, tetrakis (tri Phenylphosphine) palladium (0.35 g, 0.30 mmol), tetrahydrofuran (13 mL), and 20 wt% aqueous sodium carbonate solution (13.3 g) (25.2 mmol as sodium carbonate) were added, and the mixture was heated to reflux for 6 hours. After cooling to room temperature, the aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane) to isolate 6.2 g (9.1 mmol) of a pale yellow solid of compound (C18) (yield 91%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 675 (M +)
Example 5 (Synthesis of Compound (D16))

  In a 30 mL three-necked flask under a nitrogen stream, 2.5 g (5.1 mmol) of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole obtained in Synthesis Example 1 and 0.95 g of phenoxazine ( 5.1 mmol), sodium-tert-butoxide 0.75 g (7.7 mmol), o-xylene 12 mL, palladium acetate 10 mg (0.05 mmol), and tri (tert-butyl) phosphine 30 mg (0.16 mmol). And stirred at 140 ° C. for 5 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 2.8 g (4.4 mmol) of a yellow solid of compound (D16) was isolated (yield 86%).

FDMS (m / z); 628 (M +)
Example 6 (Synthesis of Compound (E13))

  In a 30 mL three-necked flask under a nitrogen stream, 2.3 g (6.3 mmol) of 6-bromo-2,3-diphenylquinoxaline, 2.1 g (6.3 mmol) of 3,9-bicarbazole, 1.3 g of potassium carbonate ( 9.5 mmol), 11 mL of o-xylene, 14 mg (0.06 mmol) of palladium acetate, and 38 mg (0.19 mmol) of tri (tert-butyl) phosphine were added and stirred at 140 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 3.5 g (5.7 mmol) of a yellow solid of compound (E13) was isolated (yield 90%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 612 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.51 (s, 1H), 8.42 (d, 1H), 8.33 (s, 1H), 8.09-8.20 (m, 4H), 7.80 (d, 1H), 7.67 (d, 1H), 7.49-7.60 (m, 6H), 7.27-7.43 (m, 13H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.53, 154.01, 141.96, 141.79, 141.17, 140.23, 139.55, 138.80, 138.75, 138 68, 131.13, 130.58, 129.86, 129.15, 129.08, 128.82, 128.38, 126.98, 125.94, 125.89, 125.75, 124.95. , 123.41, 123.15, 121.08, 120.74, 120.28, 119.66, 119.61, 110.96, 110.19, 109.77.
Example 7 (Synthesis of Compound (G1))

  In a 30 mL three-necked flask under a nitrogen stream, 3.1 g (8.7 mmol) of 6-bromo-2,3-diphenylquinoxaline, 2.9 g (8.7 mmol) of benzo [a] carbazole, 1.8 g of potassium carbonate (13 0.1 mmol), o-xylene 16 mL, palladium acetate 20 mg (0.09 mmol), and tri (tert-butyl) phosphine 53 mg (0.26 mmol) were added, and the mixture was stirred at 140 ° C. for 8 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 3.8 g (7.6 mmol) of a yellow solid of compound (G1) was isolated (yield 87%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 497 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.49 (s, 1H), 8.38 (d, 1H), 8.21-8.28 (m, 2H), 8.01 (d, 1H), 7.77-7.81 (m, 2H), 7.53-7.63 (m, 5H), 7.33-7.45 (m, 10H), 7.19 (t, 1H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.51, 154.30, 141.90, 141.69, 141.36, 140.76, 138.80, 138.67, 135.31, 133 .52, 131.05, 130.95, 129.89, 129.88, 129.26, 129.19, 129.16, 128.40, 128.36, 128.29, 125.31, 125.20 , 124.86, 123.89, 122.35, 121.69, 121.88, 120.88, 120.31, 119.68, 119.03, 110.29.
Example 8 (Synthesis of Compound (H1))

  In a 30 mL three-necked flask under a nitrogen stream, 2.6 g (7.3 mmol) of 6-bromo-2,3-diphenylquinoxaline, 1.6 g (7.3 mmol) of benzo [b] carbazole, 1.5 g of potassium carbonate (10 0.9 mmol), 13 mL of o-xylene, 16 mg (0.16 mmol) of palladium acetate, and 44 mg (0.22 mmol) of tri (tert-butyl) phosphine were added and stirred at 140 ° C. for 10 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 3.2 g (6.4 mmol) of a yellow solid of compound (H1) was isolated (yield 88%).

The compound was identified by FDMS and ¹ H-NMR measurement.

FDMS (m / z); 497 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.64 (s, 1H), 8.51 (s, 1H), 8.44 (d, 1H), 8.30 (d, 1H), 8 .10 (t, 2H), 7.94 (s, 1H), 7.87 (d, 1H), 7.35-7.58 (m, 15H)
Example 9 (Synthesis of Compound (J5))

  Under a nitrogen stream, in a 30 mL three-necked flask, 2.3 g (5.1 mmol) of 6-bromo-2,3-di (1-naphthyl) quinoxaline, 1.1 g (5.1 mmol) of benzo [c] carbazole, potassium carbonate 1.0 g (7.6 mmol), 11 mL of o-xylene, 11 mg (0.05 mmol) of palladium acetate, and 31 mg (0.15 mmol) of tri (tert-butyl) phosphine were added and stirred at 140 ° C. for 10 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 2.6 g (4.3 mmol) of a yellow solid of compound (J5) was isolated (yield 85%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 597 (M +)
Example 10 (Synthesis of Compound (K1))

  In a 30 mL three-necked flask under a nitrogen stream, 1.3 g (3.6 mmol) of 6-bromo-2,3-diphenylquinoxaline, 0.99 g (3.6 mmol) of dibenzo [a, c] carbazole, 0.77 g of potassium carbonate (5.5 mmol), 7 mL of o-xylene, 8 mg (0.04 mmol) of palladium acetate, and 22 mg (0.11 mmol) of tri (tert-butyl) phosphine were added, and the mixture was stirred at 140 ° C. for 7 hours. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 1.8 g (3.3 mmol) of a yellow solid of compound (K1) was isolated (yield 89%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 547 (M +)
Example 11 (Synthesis of Compound (N6))

  In a 30 mL three-necked flask under a nitrogen stream, 1.3 g (3.6 mmol) of 6-bromo-2,3-di (2-naphthyl) quinoxaline, 1.1 g (4.3 mmol) of dibenzo [a, g] carbazole, 0.90 g (6.5 mmol) of potassium carbonate, 10 mL of o-xylene, 10 mg (0.04 mmol) of palladium acetate, and 26 mg (0.13 mmol) of tri (tert-butyl) phosphine were added and stirred at 140 ° C. for 9 hours. . After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 2.4 g (4.0 mmol) of a yellow solid of compound (N6) was isolated (yield 92%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 597 (M +)
Example 12 (Synthesis of Compound (P1))

  Under a nitrogen stream, 3.4 g (7.1 mmol) of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole obtained in Synthesis Example 1 in a 30 mL three-necked flask, 9-phenylcarbazole-2- Boronic acid 2.1 g (7.5 mmol), palladium acetate 32 mg (0.14 mmol), 2-dicyclohexylphosphino-2′4′6′-triisopropylbiphenyl 137 mg, tetrahydrofuran 12 mL, and 20 wt% aqueous potassium carbonate solution 12. 3 g (17.9 mmol as potassium carbonate) was added and heated to reflux for 10 hours. After cooling to room temperature, the aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane) to isolate 4.2 g (6.1 mmol) of a pale yellow solid of compound (P1) (yield 85%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 688 (M +)
Example 13 (Synthesis of Compound (Q1))

  Under a nitrogen stream, 4.1 g (8.6 mmol) of 2-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole obtained in Synthesis Example 1 in a 30 mL three-necked flask, 9-phenylcarbazole-3- Boronic acid 2.6 g (9.0 mmol), palladium acetate 39 mg (0.17 mmol), 2-dicyclohexylphosphino-2′4′6′-triisopropylbiphenyl 165 mg, tetrahydrofuran 15 mL, and 20 wt% aqueous potassium carbonate solution 14. 9 g (21.6 mmol as potassium carbonate) was added and heated to reflux for 9 hours. After cooling to room temperature, the aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane) to isolate 5.3 g (7.6 mmol) of a pale yellow solid of compound (Q1) (yield 89%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 688 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.48 (s, 1H), 8.38-8.43 (m, 2H), 8.16-8.28 (m, 3H), 8. 08 (d, 1H), 7.85 (s, 1H), 7.71 (t, 2H), 7.55-7.61 (m, 9H), 7.34-7.46 (m, 13H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 154.37, 153.83, 142.06, 141.35, 141.26, 141.02, 140.77, 140.33, 140.19, 139 .07,138.90,138.81,137.64,134.04,130.99,129.88,129.22,129.05,128.99,128.33,128.35,127.48 127.05, 126.08, 125.93, 123.89, 123.79, 123.45122.51, 120.75, 120.44, 120.00, 119.21, 109.99, 109.87. 109.81, 108.34.
Example 14 (Synthesis of Compound (R4))

  In a 30 mL three-necked flask under a nitrogen stream, 2.3 g (4.9 mmol) of 3-chloro-9- (2,3-diphenylquinoxalin-6-yl) carbazole and 1.8 g of 9-biphenylcarbazole-2-boronic acid ( 5.1 mmol), palladium acetate 22 mg (0.10 mmol), 2-dicyclohexylphosphino-2′4′6′-triisopropylbiphenyl 94 mg, tetrahydrofuran 10 mL, and 20 wt% aqueous potassium carbonate solution 8.4 g (12 as potassium carbonate). .2 mmol) was added and heated to reflux for 12 hours. After cooling to room temperature, the aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution. The extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane) to isolate 3.3 g (4.3 mmol) of a pale yellow solid of compound (R4) (yield 88%).

  The compound was identified by FDMS measurement.

FDMS (m / z); 764 (M +)
Example 15 (Synthesis of Compound (S1))

  In a 30 mL three-necked flask under a nitrogen stream, 2.8 g (7.7 mmol) of 6-bromo-2,3-diphenylquinoxaline, 3.1 g (7.7 mmol) of 3- (9-phenylcarbazol-3-yl) carbazole , Potassium carbonate 1.6 g (11.6 mmol), o-xylene 15 mL, palladium acetate 17 mg (0.08 mmol), and tri (tert-butyl) phosphine 47 mg (0.23 mmol) were added, and the mixture was stirred at 140 ° C. for 10 hours. did. After cooling to room temperature, 10 mL of pure water and 10 mL of tetrahydrofuran were added, and the organic layer was separated. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (a mixed solvent of toluene and hexane), and 4.8 g (6.9 mmol) of a yellow solid of compound (S1) was isolated (yield 90%).

The compound was identified by FDMS, ¹ H-NMR measurement, and ¹³ C-NMR measurement.

FDMS (m / z); 688 (M +)
¹ H-NMR (CDCl ₃ ) δ (ppm); 8.41-8.49 (m, 4H), 8.27 (t, 2H), 8.10 (d, 1H), 7.81 (t, 2H), 7.32-7.73 (m, 23H)
¹³ C-NMR (CDCl ₃ ) δ (ppm); 142.02, 141.37, 140.89, 140.11, 139.55, 139.12, 138.89, 138.84, 137.76, 135 .14, 134.12, 130.92, 129.90, 129.87, 129.08, 129.00, 128.91, 128.37, 127.46, 127.08, 126.38, 126.10 125.80, 125.59, 124.52, 124.11, 123.99, 123.54, 120.76, 120.59, 120.43, 120.00, 119.03, 118.91, 110 .11,110.05,109.89
Example 16 (Element evaluation of compound (D5))
The glass substrate on which the ITO transparent electrode (anode) having a thickness of 200 nm was laminated was subjected to ultrasonic cleaning with acetone and pure water and boiling cleaning with isopropyl alcohol. Furthermore, ultraviolet ozone cleaning was performed, and after evacuation with a vacuum pump until it was 1 × 10 ⁻⁴ Pa after installation in a vacuum deposition apparatus. First, 4,4′-bis [N- (9-phenylcarbazol-3-yl) -N-phenyl] biphenyl was deposited on the ITO transparent electrode at a deposition rate of 0.3 nm / second to form a 65 nm hole injection layer. It was. Subsequently, 4,4′-bis [N- (1-naphthyl) -N-phenyl] biphenyl (NPD) was deposited to a thickness of 10 nm at a deposition rate of 0.3 nm / second to form a hole transport layer. Subsequently, bis- (1-phenylisoquinolyl) iridium (III) acetylacetonate ((piq) ₂ Ir (acac)) as a light-emitting dopant material and compound (D5) as a host material in a weight ratio of 8:92 Thus, co-evaporation was performed at a deposition rate of 0.25 nm / second to obtain a 40 nm light-emitting layer. Next, 9,10-di (1-naphthyl) -2- (4-phenyl-1-phenyl-1H-benzo [d] imidazole) and lithium quinolinol were deposited at a deposition rate of 0:50 so that the weight ratio was 50:50. Co-deposited at 15 nm / second to form a 30 nm electron transport layer. Furthermore, silver and magnesium were co-deposited at a deposition rate of 0.5 nm / second to a weight ratio of 1:10 to form a cathode. In a nitrogen atmosphere, a sealing glass plate was bonded with a UV curable resin to obtain an organic EL element for evaluation. A current of 20 mA / cm ² was applied to the device thus fabricated, and driving voltage, current efficiency, and luminance half time were measured. The results are shown in Table 1.

Examples 17-30 (element evaluation)
Instead of compound (D5), compound (F5), (B4), (C18), (D16), (E13), (G1), (H1), (J5), (K1), (N6), (P1 ), (Q1), (R4), or an organic EL device similar to that of Example 16 was produced except that it was changed to (S1). Table 1 shows the drive voltage and current efficiency when a current of 20 mA / cm ² was applied.

Comparative Examples 1-4
The same as Example 16 except that the compound (D5) was changed to 4,4′-bis (carbazol-9-yl) biphenyl (CBP), compound (a), compound (b) or compound (c). An organic EL element was produced. Table 1 shows the drive voltage and current efficiency when a current of 20 mA / cm ² was applied.

  The organic EL device containing the quinoxaline compound of the present invention having good bipolar properties can be expected to improve the recombination efficiency of electrons and holes in the light emitting layer. Therefore, the quinoxaline compound of the present invention can provide an organic EL device having high luminance and efficiency and excellent lifetime.

Claims (6)

A quinoxaline compound represented by the general formula (1).

(Where
R ¹ and R ² are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these groups are each independently a methyl group, ethyl group, A substituent selected from the group consisting of a group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a cyano group, and a deuterium atom. One or more types], a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a cyano group, a deuterium atom, or a hydrogen atom.
R ^{3 to} R ⁵ each independently represent a hydrogen atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group.
Z is a substituent represented by any one of the following general formulas (2) to (21). )

(Where
R ⁶ , R ⁷ , R ⁹ , R ¹⁰ , R ^{12 to} R ³⁸ , R ^{40 to} R ⁴³ , R ^{45 to} R ⁴⁸ , R ^{50 to} R ⁵³ , and R ^{55 to} R ⁶⁶ are each independently hydrogen. An atom, a methyl group, a phenyl group, a naphthyl group, or a biphenyl group is represented.
R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these Each independently represents a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a quinolyl group, Having at least one substituent selected from the group consisting of a pyrimidyl group, a diphenylpyridyl group, a diphenylpyrimidyl group, a diphenyltriazyl group, a dibenzothienyl group, a dibenzofuranyl group, a cyano group, and a deuterium atom; May also be expressed.
Ar ^{1 to} Ar ⁶ are each independently an aromatic hydrocarbon group having 6 to 20 carbon atoms or a heteroaromatic group having 3 to 20 carbon atoms [these groups are each independently a methyl group, ethyl group, A substituent selected from the group consisting of a group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a phenyl group, a dibenzofuranyl group, a dibenzothienyl group, a 9-carbazolyl group, a cyano group, and a deuterium atom It may have one or more groups].
X represents a single bond, an oxygen atom or a sulfur atom. ) R ¹ and R ² are each independently a phenyl group, methylphenyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, naphthylphenyl group, phenanthrylphenyl group, pyridyl group, pyridylphenyl group, or The quinoxaline compound according to claim 1, which is a hydrogen atom. R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are each independently a phenyl group, a naphthyl group, a fluorenyl group, a phenanthryl group, a pyridyl group, a pyrimidyl group, a triazyl group, a quinolyl group, or a quinazolyl group. Group, dibenzofuranyl group, or dibenzothienyl group [these groups are each independently a methyl group, a phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, a pyridyl group, a quinolyl group, a pyrimidyl group, a diphenylpyridyl group, It may have one or more substituents selected from the group consisting of a diphenylpyrimidyl group, a diphenyltriazyl group, a dibenzothienyl group, a dibenzofuranyl group, a cyano group, and a deuterium atom]. The quinoxaline compound according to claim 1 or 2, characterized in that R ⁸ , R ¹¹ , R ³⁹ , R ⁴⁴ , R ⁴⁹ , and R ⁵⁴ are each independently a phenyl group, a methylphenyl group, a naphthyl group, a biphenyl group, a terphenyl group, a dimethylfluorenyl group, or a phenanthryl group. , Naphthylphenyl group, phenanthrylphenyl group, pyridyl group, diphenylpyridyl group, diphenylpyrimidyl group, diphenyltriazyl group, quinolyl group, quinazolyl group, phenylquinazolyl group, biphenylquinazolyl group, dibenzofuranyl The quinoxaline according to claim 1, which is a group, a dibenzothienyl group, a pyridylphenyl group, a diphenylpyrimidylphenyl group, a diphenyltriazylphenyl group, a dibenzofuranylphenyl group, or a dibenzothienylphenyl group. Compound. Ar ^{1 to} Ar ⁶ are each independently a phenyl group, methylphenyl group, naphthyl group, biphenyl group, terphenyl group, phenanthryl group, naphthylphenyl group, dibenzofuranyl group, dibenzothienyl group, dibenzofuranylphenyl group Or a dibenzothienylphenyl group. 4. The quinoxaline compound according to claim 1, wherein the quinoxaline compound is a dibenzothienylphenyl group. A light emitting material comprising the quinoxaline compound according to any one of claims 1 to 5.