JP7143670B2 - Triphenylene compound and use thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel triphenylene compound and an organic EL device using the same.

An organic EL element is a surface-emitting type element in which an organic thin film is sandwiched between a pair of electrodes. It has features such as thinness and light weight, wide viewing angle, and high-speed response, and is expected to be applied to various display elements. . An organic EL element is an element that utilizes light emitted when holes injected from the anode and electrons injected from the cathode recombine in the light-emitting layer, and its structure is a hole transport layer and a light-emitting layer. , an electron transport layer, etc. are laminated. Here, a charge transport layer such as a hole transport layer or an electron transport layer does not itself emit light, but facilitates charge injection into the light emitting layer, and the charges injected into the light emitting layer and the light emitting layer It plays the role of confining the energy of the generated excitons. Therefore, the charge transport layer is very important in reducing the driving voltage and improving the luminous efficiency of the organic EL device.

An arylamine compound having an appropriate ionization potential and hole-transporting ability is used as the hole-transporting material. ] Biphenyl (hereinafter abbreviated as NPD) is widely recognized as a standard material (for example, Non-Patent Document 1). However, since NPD does not have a sufficiently high glass transition temperature, there is a problem with device life. In addition, the drive voltage and luminous efficiency of the device using NPD for the hole transport layer did not satisfy market demands.

Against this background, development of arylamine compounds into which a condensed ring is introduced, which can ensure a high glass transition temperature and is excellent in hole-transporting properties, is underway. A triphenylene ring structure is known as an example of a condensed ring having a high glass transition temperature (see, for example, Patent Documents 1 and 2). However, it is difficult to say that the device voltage and luminous efficiency of organic EL devices using these compounds are sufficient, and further improvements have been desired.

On the other hand, triphenylene compounds that can improve the glass transition temperature, amorphousness, and thermal stability have been reported (see Patent Documents 3 and 4, for example).

Korean Patent Application Publication No. 10-2010-0045587 Chinese Patent Application Publication No. 102757300 International Publication No. 2013/157367 pamphlet JP 2016-26172 A

Journal of Applied Physics, 2004, 95, 7798

In the organic EL device, the charge transport material constantly repeats redox for charge transport, but the triphenylene compounds disclosed in Patent Documents 3 and 4 above have room for improvement in their stability against redox. rice field.

An object of the present invention is to provide a novel triphenylene compound that is more stable against oxidation and reduction than conventionally known triphenylene compounds, and an organic EL device using the triphenylene compound.

As a result of intensive studies, the present inventors have found that a triphenylene compound represented by the following general formula (1) can solve the above problems, and have completed the present invention.

(wherein Ar ¹ to Ar ⁴ are each independently a monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 30 carbon atoms, or a monocyclic, linked or condensed [these groups are each independently a substituent selected from the group consisting of a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, and a dibenzofuranyl group] may have more than ].
L ¹ and L ² are each independently a single bond or a monocyclic, linked or condensed divalent aromatic hydrocarbon group having 6 to 20 carbon atoms [these groups are each independently methyl group, ethyl group, linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, methoxy group, ethoxy group, linear, branched or cyclic alkoxy group having 3 to 18 carbon atoms, 1 to 3 carbon atoms A halogenated alkyl group, a halogenated alkoxy group having 1 to 3 carbon atoms, a monocyclic, linked or condensed aryl group having 6 to 20 carbon atoms, a monocyclic, linked or condensed ring having 6 to 18 carbon atoms aryloxy group, monocyclic, linked or condensed heteroaryl group having 3 to 20 carbon atoms, trialkylsilyl group having 3 to 18 carbon atoms, triarylsilyl group having 18 to 40 carbon atoms, cyano group, halogen atom , and deuterium atoms. ] represents.
R ¹ and R ² each independently represent a methyl group, a methoxy group, or a cyano group; n and m each independently represent an integer of 0 to 4; )

The triphenylene compound of the present invention has excellent oxidation-reduction stability based on its structural characteristics, and therefore has the effect of being able to provide a highly durable hole-transporting material. That is, it is possible to provide an organic EL element with high durability.

ADVANTAGE OF THE INVENTION The triphenylene compound of this invention is effective in being able to provide the organic electroluminescent element which has high luminous efficiency (current efficiency) and is excellent in element life compared with the conventionally well-known material.

The present invention will be described in detail below.

In the triphenylene compound represented by the above general formula (1), Ar ¹ to Ar ⁴ are each independently a monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 30 carbon atoms, or a 3 carbon atom to 20 monocyclic, linked, or fused heteroaromatic groups [each of these groups is independently selected from methyl, phenyl, triphenylsilyl, carbazolyl, dibenzothienyl, and dibenzofuranyl may have one or more substituents selected from the group consisting of].

The monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 30 carbon atoms in Ar ¹ to Ar ⁴ is not particularly limited, but examples thereof include phenyl group, biphenylyl group, terphenylyl group, naphthyl group, fluorenyl group, phenanthryl group, benzofluorenyl group, and the like. In addition, as described above, each of these groups may independently have a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, or a dibenzofuranyl group, and a substituent is not particularly limited.

The monocyclic, linked or condensed heteroaromatic group having 3 to 20 carbon atoms in Ar ¹ to Ar ⁴ is not particularly limited. A monocyclic, linked or condensed heteroaromatic group containing 3 to 20 carbon atoms can be mentioned, and more preferably at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom. A monocyclic, linked or condensed heteroaromatic group having 3 to 20 carbon atoms contained on an aromatic ring can be exemplified, but not limited to, for example, pyrrolyl group, thienyl group, furyl group and imidazolyl. group, pyrazolyl group, thiazolyl group, isothiazolyl group, oxazolyl group, isoxazolyl group, pyridyl group, pyrimidyl group, pyrazyl group, 1,3,5-triazyl group, indolyl group, benzothienyl group, benzofuranyl group, benzimidazolyl group, indazolyl group , a benzothiazolyl group, a benzoisothiazolyl group, a 2,1,3-benzothiadiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group, a 2,1,3-benzoxadiazolyl group, a quinolyl group, isoquinolyl group, quinoxalyl group, quinazolyl group, carbazolyl group, dibenzothienyl group, dibenzofuranyl group, phenoxazinyl group, phenothiazinyl group, phenazine group, thianthrenyl group and the like. In addition, as described above, each of these groups may independently have a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, or a dibenzofuranyl group, and a substituent is not particularly limited.

Specific examples of Ar ¹ to Ar ⁴ are not particularly limited, but are each independently a phenyl group, 4-methylphenyl group, 3-methylphenyl group, 2-methylphenyl group, 2,4-dimethyl phenyl group, 2,5-dimethylphenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,6-dimethylphenyl group, 2,3,5-trimethylphenyl group, 2,3,6 -trimethylphenyl group, 3,4,5-trimethylphenyl 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-1,1'-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 group, 3-(2-naphthyl) phenyl group, 3-methyl-4-(1-naphthyl) phenyl group, 3-methyl-4-( 2-naphthyl)phenyl group, 4-(2-methylnaphthalen-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)naphthalene-2-yl group, 4-(3-methylphenyl)naphthalene-2-y 4-(4-methylphenyl)naphthalen-2-yl group, tetraphenylsilane-4-yl group, tetraphenylsilane-3-yl group, 2-fluorenyl group, 9,9-dimethyl-2-fluorenyl group, 9,9-diphenyl-2-fluorenyl group, 9,9-diphenyl-4-fluorenyl group, 9,9′-spirobifluorenyl group, 9-phenanthryl group, 2-phenanthryl 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- fluoranthenyl group, 8-fluoranthenyl 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- methyl-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, 5-oxazolyl group, 3-isoxazolyl group, 4-isoxazolyl group, 5-isoxazolyl group, 2-pyridyl group, 3-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'-bipyridine -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-benzimidazolyl group, 2-phenyl-1-benzimidazolyl group , 1-methyl-2-benzimidazolyl group, 1-phenyl-2-benzimidazolyl 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, 3-benzisothiazolyl group, 4-benzisothiazolyl group, 5-benzisothiazolyl group, 6-benzisothiazolyl group, 7-benzoisothiazolyl 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-benzoisoxazolyl group, 5-benzoisoxazolyl group, 6-benzoisoxazolyl group, 7-benzoisoxazolyl group, 2,1,3-benzoxadiazolyl-4-yl group, 2,1,3-benzoxadiazolyl-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-phenanthrolin-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, 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-thiantryl 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, 4-(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-phenylimidazole-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-methylbenzimidazol-1-yl)phenyl group, 3-(2-phenylbenzimidazol-1-yl)phenyl group, 3-(1-methylbenzoy) midazol-2-yl)phenyl group, 3-(2-phenylbenzimidazol-1-yl)phenyl group, 4-(3,5-diphenyltriazin-1-yl)phenyl group, 4-(2-thienyl)phenyl group, 4-(2-furanyl)phenyl group, 5-phenylthiophen-2-yl group, 5-phenylfuran-2-yl group, 4-(5-phenylthiophen-2-yl)phenyl group, 4-( 5-phenylfuran-2-yl)phenyl group, 3-(5-phenylthiophen-2-yl)phenyl group, 3-(5-phenylfuran-2-yl)phenyl group, 4-(2-benzothienyl) Phenyl group, 4-(3-benzothienyl) phenyl 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-dibenzofuranyl) 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, or 3-(9-carbazolyl)phenyl group can be exemplified, but not limited to these.

In the triphenylene compound represented by the general formula (1), Ar ¹ to Ar ⁴ are each independently a monocyclic, linked, or condensed aromatic having 6 to 20 carbon atoms in terms of excellent hole-transporting properties. group hydrocarbon groups, or monocyclic, linked or condensed heteroaromatic groups having 3 to 16 carbon atoms [these groups are each independently a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzo may have one or more substituents selected from the group consisting of a thienyl group and a dibenzofuranyl group], each independently of a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, fluorenyl group, phenanthryl group, dibenzothienyl group, or dibenzofuranyl group [these groups are each independently selected from methyl, phenyl, triphenylsilyl, carbazolyl, dibenzothienyl, and dibenzofuranyl may have one or more substituents selected from the group consisting of].

The above monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 20 carbon atoms is not particularly limited, but the above monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 30 carbon atoms Groups similar to hydrocarbon groups (limited to those having 6 to 20 carbon atoms) can be exemplified.

The monocyclic, linked, or condensed heteroaromatic group having 3 to 16 carbon atoms is not particularly limited, but the monocyclic, linked, or condensed heteroaromatic group having 3 to 20 carbon atoms Groups similar to the group (limited to those having 3 to 16 carbon atoms) can be exemplified.

In the triphenylene compound represented by the general formula (1), Ar ¹ to Ar ⁴ each independently represent a methyl group, a triphenylsilyl group, a carbazolyl group, or a dibenzothienyl group in terms of excellent hole-transporting properties. and a dibenzofuranyl group, a phenyl group optionally having a substituent selected from the group consisting of a dibenzofuranyl group, a biphenylyl group optionally having a methyl group, a terphenylyl group optionally having a methyl group, a methyl group a naphthyl group optionally having a methyl group or a fluorenyl group optionally having a phenyl group, a phenanthryl group optionally having a methyl group, a dibenzothienyl group optionally having a methyl group, A dibenzofuranyl group optionally having a methyl group is more preferred.

Further, in the triphenylene compound represented by the general formula (1), Ar ¹ to Ar ⁴ are each independently a phenyl group, a 4-methylphenyl group, a 4-(9 -carbazolyl)phenyl group, dibenzothienyl group, dibenzofuranyl group, 4-(4-dibenzothienyl)phenyl group, 4-(4-dibenzofuranyl)phenyl group, biphenylyl group, terphenylyl group, naphthyl group, 9,9 -dimethyl-2-fluorenyl group, 9,9-diphenyl-2-fluorenyl group, or phenanthryl group is more preferable.

In the triphenylene compound represented by the general formula (1), L ¹ and L ² are each independently a single bond or a monocyclic, linked or condensed bivalent aromatic carbonized ring having 6 to 20 carbon atoms. A hydrogen group [each of these groups is independently a methyl group, an ethyl group, a linear, branched or cyclic alkyl group having 3 to 18 carbon atoms, a methoxy group, an ethoxy group, a linear group having 3 to 18 carbon atoms, , a branched or cyclic alkoxy group, a halogenated alkyl group having 1 to 3 carbon atoms, a halogenated alkoxy group having 1 to 3 carbon atoms, a monocyclic, linked or condensed aryl group having 6 to 20 carbon atoms, carbon 6 to 18 monocyclic, linked or condensed aryloxy groups, monocyclic, linked or condensed heteroaryl groups of 3 to 20 carbon atoms, trialkylsilyl groups of 3 to 18 carbon atoms, carbon atoms It may have one or more substituents selected from the group consisting of 18 to 40 triarylsilyl groups, cyano groups, halogen atoms and deuterium atoms. ] represents.

Specific examples of the monocyclic, linked, or condensed divalent aromatic hydrocarbon group having 6 to 20 carbon atoms represented by L ¹ and L ² are not particularly limited, but include, for example, a phenylene group and biphenylene. terphenylene group, naphthylene group, phenylnaphthalene-diyl group, binaphthylene group, fluorene-diyl group, benzofluorene-diyl group, dibenzofluorene-diyl group, phenanthrene-diyl group, fluoranthene-diyl group, anthracene-diyl group, chrysene-diyl group, pyrene-diyl group, triphenylene-diyl group, perylene-diyl group, and the like.

Linear, branched or cyclic alkyl groups having 3 to 18 carbon atoms are not particularly limited, but examples include propyl, isopropyl, butyl, sec-butyl, tert-butyl and pentyl groups. , a hexyl group, a heptyl group, an octyl group, a stearyl group, a cyclopropyl group, a cyclohexyl group, and the like.

Examples of linear, branched or cyclic alkoxy groups having 3 to 18 carbon atoms include, but are not limited to, propoxy, isopropoxy, n-butoxy, sec-butoxy and tert-butoxy groups. , pentyloxy group, hexyloxy group, or stearyloxy group.

Examples of the halogenated alkyl group having 1 to 3 carbon atoms include, but are not particularly limited to, a trifluoromethyl group, a trichloromethyl group, a 2-fluoroethyl group, and the like.

Examples of halogenated alkoxy groups having 1 to 3 carbon atoms include, but are not limited to, trifluoromethoxy, trichloromethoxy, 2-fluoroethoxy and the like.

A monocyclic, linked or condensed aryl group having 6 to 20 carbon atoms is a monocyclic, linked or condensed aromatic hydrocarbon group having a total of 6 to 20 carbon atoms and optionally having substituents. Examples of the group include, but are not limited to, phenyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 2-methoxyphenyl group, and 3-methoxyphenyl group. , 4-methoxyphenyl group, 2-cyanophenyl group, 3-cyanophenyl group, 4-cyanophenyl group, 3,4-dimethylphenyl group, 2,6-dimethylphenyl group, biphenyl group, naphthyl group, 1-methyl naphthyl group, 2-methylnaphthyl group, 1-methoxynaphthyl group, 2-methoxynaphthyl group, 9,9-dimethylfluorenyl group and the like.

The monocyclic, linked or condensed aryloxy group having 6 to 18 carbon atoms is not particularly limited, but examples thereof include phenoxy group, 2-methylphenoxy group, 3-methylphenoxy group, 4-methylphenoxy group, 2-methoxyphenoxy group, 3-methoxyphenoxy group, 4-methoxyphenoxy group, 2-cyanophenoxy group, 3-cyanophenoxy group, 4-cyanophenoxy group, 3,4-dimethylphenoxy group, 2,6- A dimethylphenoxy group, a biphenyloxy group, a naphthyloxy group, and the like can be mentioned.

A monocyclic, linked or condensed heteroaryl group having 3 to 20 carbon atoms is an optionally substituted monocyclic, linked or condensed heteroaryl group having a total of 3 to 20 carbon atoms. Examples of the group include, but are not limited to, pyrrolyl group, 1-methylpyrrolyl group, 1-phenylpyrrolyl group, thienyl group, 2-methylthienyl group, 2-cyanothienyl group, 2- phenylthienyl group, furyl group, 2-phenylfuryl group, imidazolyl group, 1-methylimidazolyl group, 2-methylimidazolyl group, 1-phenylimidazolyl group, 2-phenyl-imidazolyl group, pyrazolyl group, thiazolyl group, isothiazolyl group, oxazolyl group, isoxazolyl group, pyridyl group, pyrimidyl group, pyrazyl group, 1,3,5-triazyl group, 2,4-diphenyl-1,3,5-triazyl group, indolyl group, benzothienyl group, benzofuranyl group, benzimidazolyl group, 2-methylbenzimidazolyl group, 2-phenylbenzimidazolyl group, 1-methylbenzimidazolyl group, 1-phenylbenzimidazolyl group, 1,2-diphenylbenzimidazolyl group, indazolyl group, benzothiazolyl group, benzisothiazolyl group, 2,1, 3-benzothiadiazolyl group, benzoxazolyl group, benzoisoxazolyl group, 2,1,3-benzoxadiazolyl group, quinolyl group, isoquinolyl group, quinoxalyl group, quinazolyl group, carbazolyl group, 9- methylcarbazolyl group, 9-ethylcarbazolyl group, 9-phenylcarbazolyl group, dibenzothienyl group, dibenzofuranyl group, phenoxazinyl group, phenothiazinyl group, acridinyl group, phenanthroline group, phenazine group, or thianthrenyl group etc.

Examples of the trialkylsilyl group having 3 to 18 carbon atoms include, but are not limited to, trimethylsilyl group, triethylsilyl group, tributylsilyl group, and the like.

The triarylsilyl group having 18 to 40 carbon atoms is not particularly limited, and examples thereof include triphenylsilyl group, tri(2-methylphenyl)silyl group, tri(3-methylphenyl)silyl group, tri( 4-methylphenyl)silyl group, tri(4-biphenylyl)silyl group and the like.

Halogen atoms include fluorine, chlorine, bromine, or iodine.

In the triphenylene compound represented by the general formula (1), L ¹ and L ² are each independently a single bond, a monocyclic ring having 6 to 14 carbon atoms, a linkage, or A condensed divalent aromatic hydrocarbon group [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 methoxy group, an ethoxy group, a carbon a linear, branched or cyclic alkoxy group having 3 to 18 carbon atoms, a halogenated alkyl group having 1 to 3 carbon atoms, a halogenated alkoxy group having 1 to 3 carbon atoms, a monocyclic ring having 6 to 20 carbon atoms, linked, or condensed aryl group, monocyclic, linked or condensed aryloxy group having 6 to 18 carbon atoms, monocyclic, linked or condensed heteroaryl group having 3 to 20 carbon atoms, trialkylsilyl having 3 to 18 carbon atoms , a triarylsilyl group having 18 to 40 carbon atoms, a cyano group, a halogen atom, and a deuterium atom. ] is preferable.

The above monocyclic, linked or condensed divalent aromatic hydrocarbon group having 6 to 14 carbon atoms is not particularly limited, but the above monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 20 carbon atoms Groups similar to divalent aromatic hydrocarbon groups (limited to those having 6 to 14 carbon atoms) can be exemplified.

L ¹ and L ² are each independently a single bond, a phenylene group, or a biphenylene group (these groups are methyl, ethyl, straight chain, branched or cyclic alkyl group, methoxy group, ethoxy group, linear, branched or cyclic alkoxy group having 3 to 18 carbon atoms, halogenated alkyl group having 1 to 3 carbon atoms, 1 to 3 carbon atoms Halogenated alkoxy group, C6-20 monocyclic, linked or condensed aryl group, C6-18 monocyclic, linked or condensed aryloxy group, C3-20 monocyclic, linked , or a substituent selected from the group consisting of a condensed heteroaryl group, a trialkylsilyl group having 3 to 18 carbon atoms, a triarylsilyl group having 18 to 40 carbon atoms, a cyano group, a halogen atom, and a deuterium atom. more preferably each independently a single bond, a phenylene group or a biphenylene group, each independently a single bond, a 1,3-phenylene group, A 1,4-phenylene group or a 4,4'-biphenylene group is more preferred, and each independently a single bond, a 1,3-phenylene group, or a 1,4-phenylene group is more preferred. .

In the triphenylene compound represented by the general formula (1), R ¹ and R ² each independently represent a methyl group, a methoxy group, or a cyano group. R ¹ and R ² are each independently preferably a methyl group or a cyano group in terms of excellent hole transport properties.

n and m each independently represent an integer of 0 to 4; n and m are each independently preferably 0, 1, 2, or 3, more preferably 0, 1, or 2, and 0 or 1 from the viewpoint of excellent hole transport properties. 0 is more preferable.

Preferred triphenylene compounds represented by formula (1) are exemplified below, but the present invention is not limited to these compounds.

The triphenylene compound represented by the general formula (1) can be synthesized by a known method (aryl amination and Suzuki coupling) using, for example, a dihalogenated triphenylene compound as a raw material. For example, a dihalogenated triphenylene compound represented by the following general formula (2) and an arylamine compound represented by the general formula (3) or (4) are combined in the presence of a base with a copper catalyst or a palladium catalyst. to obtain the corresponding triphenylene compound represented by general formula (5) or general formula (6). Furthermore, the obtained triphenylene compound represented by general formula (5) or general formula (6) and the arylamine compound represented by general formula (4) or general formula (3), respectively, are combined in the presence of a base. , a copper catalyst or a palladium catalyst. The triphenylene compound represented by the general formula (1) can be synthesized in two steps or in one step as shown above.

[In the formula, R ¹ and R ² , Ar ¹ to Ar ⁴ , L ¹ , L ² , m and n have the same definition as in the general formula (1). Each of X and Y independently represents a halogen atom (iodine, bromine, chlorine, or fluorine) or a triflate group. Z represents B(OH) ₂ or its ester, or a hydrogen atom. ]
Further, the dihalogenated triphenylene compound represented by the general formula (2) can be synthesized by a known method (Angewandte Chemie International Edition, 2012, Vol. 51, p. 12293).

The triphenylene compound represented by the general formula (1) of the present invention can be used as a material for an organic EL device, and more specifically, it can be used as a light emitting layer, a hole transport layer or a hole injection Can be used as a layer. The triphenylene compound represented by the general formula (1) preferably has high purity in terms of hole transport properties and device life. Specifically, it is preferable to use as few impurities as possible such as impurities due to halogen atoms and transition metal elements, and impurities such as production raw materials and by-products.

When the triphenylene compound represented by the general formula (1) is used as a hole injection layer or a hole transport layer of an organic EL device, the light-emitting layer includes a conventionally used known fluorescent or phosphorescent light-emitting material, Alternatively, thermally activated delayed fluorescence materials can be used. The light-emitting layer may be formed of only one light-emitting material, or the host material may be doped with one or more light-emitting materials.

When forming the hole injection layer and/or the hole transport layer containing the triphenylene compound represented by the general formula (1), two or more materials may be contained or laminated as necessary, For example, oxides such as molybdenum oxide, 7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, hexacyanohexa A known electron-accepting material such as azatriphenylene may be contained or laminated.

Moreover, the triphenylene compound represented by the general formula (1) of the present invention can also be used as a light-emitting layer of an organic EL device. When the triphenylene compound represented by the general formula (1) is used as the light-emitting layer of an organic EL device, the triphenylene compound is used alone, used by being doped with a known light-emitting host material, or a known light-emitting dopant is used. Can be used by doping.

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

The basic structure of an organic EL device that can achieve the effects of the present invention preferably includes a substrate, an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and a cathode. Layers may be omitted and vice versa.

The anode and cathode of the organic EL element are connected to a power source through electrical conductors. By applying an electric potential between the anode and cathode, the organic EL element is activated and emits light.

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

An organic EL element is typically overlaid on a substrate, and the anode or cathode can be in contact with the substrate. The electrode in contact with the substrate is conveniently called the bottom electrode. Although the lower electrode is generally an anode, 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 direction of light emission. The light transmission properties can be confirmed by electroluminescence emission through the substrate. Generally, transparent glass or plastic is employed as the substrate in such cases. The substrate may be a composite structure comprising multiple layers of material.

If the electroluminescent emission is to be seen through the anode, the anode is made to pass or substantially pass the emission.

Common transparent anode (anode) materials used in the present invention include, but are not limited to, indium-tin oxide (ITO), indium-zinc oxide (IZO), or 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 fluorocarbons. If the electroluminescent emission is seen only through the cathode, the transmissive properties of the anode are not critical and any conductive material, 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 layers of hole-transporting layers such as a hole-injecting layer and a hole-transporting layer can be provided between the anode and the light-emitting layer. The hole-injecting layer and the hole-transporting layer have the function of transferring holes injected from the anode to the light-emitting layer. of holes can be injected into the light-emitting layer.

In the organic EL device of the present invention, the hole-transporting layer and/or the hole-injecting layer contain the triphenylene compound represented by the general formula (1).

For the hole-transporting layer and/or the hole-injecting layer, the triphenylene compound represented by the general formula (1) is selected arbitrarily from known hole-transporting materials and/or hole-injecting materials. can be used in combination.

Examples of known hole injection materials and hole transport materials include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, Examples include oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, conductive polymer oligomers, especially thiophene oligomers. As the hole-injecting material and the hole-transporting material, those mentioned 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 compounds and styrylamine compounds 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) Audryphenyl, N,N,N-tri(p-tolyl)amine, 4-(di-p-tolylamino)-4'-[4-(di-p-tolylamino)styryl]stilbene, 4-N,N- Diphenylamino-(2-diphenylvinyl)benzene, 3-methoxy-4'-N,N-diphenylaminostilbenzene, N-phenylcarbazole, 4,4'-bis[N-(1-naphthyl)-N-phenyl amino]biphenyl (NPD), 4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (MTDATA) and the like.

Inorganic compounds such as p-type Si and p-type SiC can also be used as hole injection materials and hole transport materials. 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 laminated structure composed of a plurality of layers having the same composition or different compositions.

The light-emitting layer of an organic EL device contains a phosphorescent or fluorescent material in which light is emitted as a result of recombination of electron-hole pairs.

The light-emitting layer may consist of a single material, including both small molecules and polymers, but more commonly consists of a host material doped with a guest compound, with light emission coming primarily from the dopant and any can have color.

Host materials for the light-emitting layer include, for example, 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.

The host material in the light-emitting layer may be an electron-transporting material as defined below, a hole-transporting material as defined above, another material that assists (supports) hole-electron recombination, or a combination of these materials. good.

Examples of fluorescent dopants include anthracene, pyrene, tetracene, xanthene, perylene, rubrene, coumarin, rhodamine, quinacridone, dicyanomethylenepyran compounds, thiopyran compounds, polymethine compounds, pyrylium or thiapyrylium compounds, fluorene derivatives, periflanthene derivatives, indenoperylenes. derivatives, bis(azinyl)amine boron compounds, bis(azinyl)methane compounds, carbostyril compounds and the like.

Examples of phosphorescent dopants include organometallic complexes of transition metals such as iridium, platinum, palladium and osmium.

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

Electron-transporting materials include alkali metal complexes, alkaline earth metal complexes, earth metal complexes, and the like. Examples of alkali metal complexes, alkaline earth metal complexes, or earth metal complexes include lithium 8-hydroxyquinolinato (Liq), bis(8-hydroxyquinolinato)zinc, bis(8-hydroxyquinolinato) copper, bis(8-hydroxyquinolinato)manganese, tris(8-hydroxyquinolinato)aluminum, tris(2-methyl-8-hydroxyquinolinato)aluminum, tris(8-hydroxyquinolinato)gallium, Bis (10-hydroxybenzo [h] quinolinate) beryllium, bis (10-hydroxybenzo [h] quinolinate) zinc, bis (2-methyl-8-quinolinate) chlorogallium, bis (2-methyl-8-quinolinate) ( o-cresolato)gallium, bis(2-methyl-8-quinolinato)-1-naphtholatoaluminum, bis(2-methyl-8-quinolinato)-2-naphtholatogallium, and the like.

A hole-blocking layer may be provided between the light-emitting layer and the electron-transporting layer for the purpose of improving carrier balance. Preferred 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, luminous efficiency, constant voltage drive, or high durability).

Preferred compounds for the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, frelenylidenemethane, anthraquinodimethane, anthrone, and the like. is mentioned. In addition, the above 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, Inorganic compounds such as various oxides such as GeO, LiO, LiON, TiO, TiON, TaO, TaON, TaN, C, nitrides, and oxynitrides can also be used.

The cathode used in the present invention can be formed from any electrically conductive material, provided that light emission is only seen through the anode. Preferred cathode materials include sodium, sodium-potassium alloys, magnesium, lithium, magnesium/copper mixtures, magnesium/silver mixtures, magnesium/aluminum mixtures, magnesium/indium mixtures, aluminum/aluminum oxide (Al ₂ O ₃ ) mixtures, indium , lithium/aluminum mixtures, rare earth metals, and the like.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention should not be construed as being limited to these examples.

Analytical instruments and measuring methods used in this example are listed below.

[Material purity measurement (HPLC analysis)]
Measuring device: Multi-station LC-8020 manufactured by Tosoh
Measurement conditions: column Inertsil ODS-3V (4.6 mmΦ × 250 mm)
Detector UV detection (wavelength 254 nm)
Eluent methanol/tetrahydrofuran = 9/1 (v/v ratio)
[NMR measurement]
Measuring device: Gemini200 manufactured by Varian
[Mass spectrometry]
Mass spectrometer: M-80B manufactured by Hitachi, Ltd.
Measurement method: FD-MS analysis [Redox stability evaluation]
Measuring device: HSV-110 manufactured by Hokuto Denko Co., Ltd.
[Emission characteristics of organic EL element]
Measuring device: TOPCON LUMINANCEMETER (BM-9)

Synthesis Example 1 Synthesis of Compound (7) Under a nitrogen stream, 29.5 g (149.2 mmol) of 2-biphenylboronic acid and 43.8 g of 1-pyrrolidinylazo-2-bromo-4,6-dichlorobenzene ( 135.6 mmol), 3.1 g (2.7 mmol) of tetrakis(triphenylphosphine) palladium, 400 mL of 1,2-dimethoxyethane, and 284 g of a 30 wt% tripotassium phosphate aqueous solution (406.8 mmol as tripotassium phosphate) were added, Stir at 80° C. for 18 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 sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio=3:1)) to isolate 41.9 g (105.7 mmol) of compound (7) as a pale yellow solid. rate 78%).

Identification of the compound was carried out by ¹ H-NMR measurement.

¹ H-NMR (CDCl ₃ ); 7.34 (d, 2H), 7.28 (d, 2H), 7.21-7.12 (m, 6H), 6.91 (d, 1H), 3 .40 (br-S, 4H), 1.88 (br-S, 4H)
Synthesis Example 2 Synthesis of Compound (8) Under a nitrogen stream, 39.4 g (99.4 mmol) of compound (7) obtained in Synthesis Example 1 was charged into a 1000 mL three-necked flask and dissolved in 600 mL of dichloromethane. After that, 28.2 g (198.8 mmol) of boron trifluoride-diethyl ether complex was added and stirred at 40° C. for 5 hours. After cooling to room temperature, 200 mL of saturated sodium hydrogen carbonate aqueous solution was added. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. 600 mL of methanol was added to the residue to the reaction solution, the deposited precipitate was collected by filtration, and further washed with methanol to isolate 19.2 g (64.6 mmol) of a white solid compound (8) (yield 65% ).

The compounds were identified by ¹ H-NMR measurement and ¹³ C-NMR measurement.

¹ H-NMR (CDCl ₃ ); 9.44 (d, 1H), 8.54 (t, 2H), 8.45 (s, 1H), 8.39 (d, 1H), 7.66-7 .40 (m, 5H)
¹³ C-NMR (CDCl ₃ ); .42, 125.95, 123.64, 123.20, 123.14, 121.92

Synthesis Example 3 Synthesis of compound (9) Under a nitrogen stream, 6.7 g (34.0 mmol) of 2-biphenylboronic acid, 13.7 g (37 .4 mmol), 0.78 g (0.68 mmol) of tetrakis(triphenylphosphine)palladium, 100 mL of 1,2-dimethoxyethane, and 71 g of a 30 wt % tripotassium phosphate aqueous solution (102.0 mmol as tripotassium phosphate) were added, and 80 C. for 18 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 sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio=3:1)) to isolate 12.4 g (28.1 mmol) of compound (9) as a pale yellow solid. rate 83%).

Identification of the compound was carried out by ¹ H-NMR measurement.

¹ H-NMR (CDCl ₃ ); 7.46 (d, 1H), 7.34 (d, 2H), 7.23-7.13 (m, 7H), 6.93 (d, 1H), 3 .40 (br-S, 4H), 1.88 (br-S, 4H)
Synthesis Example 4 Synthesis of Compound (10) Under a nitrogen stream, 10.8 g (24.6 mmol) of compound (9) obtained in Synthesis Example 3 was charged into a 1000 mL three-necked flask and dissolved in 400 mL of dichloromethane. After that, 7.0 g (49.2 mmol) of boron trifluoride-diethyl ether complex was added and stirred at 40° C. for 12 hours. After cooling to room temperature, 80 mL of saturated aqueous sodium hydrogen carbonate solution was added. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. 200 mL of methanol was added to the residue to the reaction solution, the deposited precipitate was collected by filtration, and further washed with methanol to isolate 5.8 g (17.0 mmol) of a white solid compound (10) (yield 69%). ).

Identification of the compound was carried out by ¹ H-NMR measurement.

¹ H-NMR (CDCl ₃ ); 9.48 (d, 1H), 8.59-8.55 (m, 3H), 8.45 (d, 1H), 7.94 (d, 1H), 7 .71-7.56 (m, 4H)
Synthesis Example 5 Synthesis of Compound (11) Under a nitrogen stream, 3.6 g (10.5 mmol) of 1-bromo-3-chlorotriphenylene obtained in Synthesis Example 4 and 3.2 g of triphenylamine boronic acid were placed in a 200 mL three-necked flask. (11.1 mmol), 0.18 g (0.16 mmol) of tetrakis(triphenylphosphine) palladium, 30 mL of 1,2-dimethoxyethane, and 22 g of 20 wt% potassium carbonate aqueous solution (31.6 mmol as potassium carbonate) were added, and 80 °C for 6 hours. After cooling to room temperature, the precipitated solid was filtered and washed with methanol. The residue was recrystallized (toluene/butanol) to isolate 3.3 g (6.6 mmol) of compound (11) as a white solid (yield 63%).

Identification of the compounds was carried out by FDMS and ¹ H-NMR measurements.

FDMS (m/z); 505 (M+)
¹ H-NMR (CDCl ₃ ); 8.61-8.52 (m, 4H), 7.86 (d, 1H), 7.68 (t, 2H), 7.54-7.48 (m, 2H), 7.33-7.12 (m, 13H), 7.05 (t, 2H)
Example 1 (Synthesis of compound (A7))

Under a nitrogen stream, 1.5 g (5.0 mmol) of 1,3-dichlorotriphenylene obtained in Synthesis Example 2, 2.1 g (10.1 mmol) of N-phenyl-4-biphenylamine, sodium- 1.3 g (13.0 mmol) of tert-butoxide and 20 mL of o-xylene were added, and 33.7 mg (0.15 mmol) of palladium acetate and 91.0 mg of tri-tert-butylphosphine were added to the resulting slurry reaction mixture. (0.45 mmol) was added and stirred at 140° C. for 24 hours. After cooling to room temperature, 20 mL of pure water was added and stirred. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio = 1:1)) to isolate 1.2 g (1.7 mmol) of white powder of compound (A7) (yield 34%).

Compound identification was performed by FDMS.

FDMS (m/z); 714 (M+)
Example 2 (Synthesis of compound (A9))

Under a nitrogen stream, 2.1 g (7.0 mmol) of 1,3-dichlorotriphenylene obtained in Synthesis Example 2, 4.6 g (14.4 mmol) of bis(4-biphenylyl)amine, sodium-tert were placed in a 100 mL three-necked flask. -Butoxide 1.8 g (18.2 mmol) and o-xylene 30 mL were added, and the resulting slurry reaction mixture was palladium acetate 47.1 mg (0.21 mmol) and tri-tert-butylphosphine 127.5 mg ( 0.63 mmol) was added and stirred at 140° C. for 24 hours. After cooling to room temperature, 30 mL of pure water was added and stirred. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio = 1:1)), and the residue obtained by concentration under reduced pressure was recrystallized (toluene/butanol) to give the compound ( 3.6 g (4.1 mmol) of pale yellow powder of A9) was isolated (yield 59%).

Compound identification was performed by FDMS.

FDMS (m/z); 866 (M+)
Example 3 (Synthesis of compound (A15))

Example 2 except that 4.3 g (14.4 mmol) of 4-(naphthalen-2-yl)-N-phenylamine was used instead of 4.6 g (14.4 mmol) of bis(4-biphenylyl)amine. A similar operation was performed to isolate 2.4 g (2.9 mmol) of pale yellow powder of compound (A15) (yield 42%).

Compound identification was performed by FDMS.

FDMS (m/z); 814 (M+)
Example 4 (Synthesis of compound (A79))

Under a nitrogen stream, 0.51 g (1.0 mmol) of the compound (11) obtained in Synthesis Example 5, 1.0 g (11.1 mmol) of N-phenyl-4-biphenylamine, sodium-tert- 0.12 g (18.2 mmol) of butoxide and 10 mL of o-xylene were added, and 2.2 mg (0.01 mmol) of palladium acetate and 6.1 mg (0 .03 mmol) was added and stirred at 140° C. for 18 hours. After cooling to room temperature, 30 mL of pure water was added and stirred. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio = 1:1)) to isolate 0.45 g (0.63 mmol) of compound (A79) as a white powder (yield: 63%).

Compound identification was performed by FDMS.

FDMS (m/z); 714 (M+)
Example 5 (Synthesis of compound (A80))

Under a nitrogen stream, 1.5 g (3.0 mmol) of compound (11) obtained in Synthesis Example 5, 0.99 g (3.1 mmol) of bis(4-biphenylyl)amine, and sodium-tert-butoxide were placed in a 100 mL three-necked flask. 0.37 g (3.9 mmol) and 20 mL of o-xylene were added, and 3.4 mg (0.015 mmol) of palladium acetate and 9.1 mg (0.015 mmol) of palladium acetate and 9.1 mg (0. 045 mmol) was added and stirred at 140° C. for 18 hours. After cooling to room temperature, 30 mL of pure water was added and stirred. The aqueous layer and the organic layer were separated, and the organic layer was washed with a saturated aqueous sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (mixed solvent of toluene and hexane (volume ratio = 1:1)), and the residue obtained by concentration under reduced pressure was recrystallized (toluene/butanol) to give the compound ( A80) was isolated 2.0 g (2.5 mmol) of white powder (84% yield).

Compound identification was performed by FDMS.

FDMS (m/z); 790 (M+)
Example 6 (Synthesis of compound (A199))

Under a nitrogen stream, 1.2 g (4.0 mmol) of 1,3-dichlorotriphenylene obtained in Synthesis Example 2, 2.5 g (8.8 mmol) of triphenylamine boronic acid, and 9.0 mg of palladium acetate were placed in a 100 mL three-necked flask. (0.04 mmol), 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl 38.0 mg (0.08 mmol), tetrahydrofuran 15 mL, and 20 wt % potassium carbonate aqueous solution 14 g (20.0 wt % as potassium carbonate). 0 mmol) was added and stirred at 70° C. for 8 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 sodium chloride solution. The organic layer was then dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. By recrystallizing the residue (toluene/butanol), 2.5 g (3.5 mmol) of pale yellow solid compound (A199) was isolated (yield 87%).

Compound identification was performed by FDMS.

FDMS (m/z); 714 (M+)
Example 7 (Evaluation of redox stability of compound (A79))
The redox stability of compound (A79) was evaluated by cyclic voltammetry. The compound (A79) was dissolved at a concentration of 0.001 mol/L in an anhydrous dichloromethane solution having a concentration of tetrabutylammonium perchlorate of 0.1 mol/L, and glassy carbon was used as the working electrode, a platinum wire was used as the counter electrode, and a platinum wire was used as the reference electrode. Cyclic voltammograms of compound (A79) were obtained using a silver wire soaked in an acetonitrile solution of AgNO ₃ (Fig. 1). Compound (A79) exhibited a reversible redox wave and was stable against redox.

Comparative Example 1 (Evaluation of redox stability of compound (a))
In the same manner as in Example 7, the oxidation-reduction stability of (compound 1) described on page 12 of WO 2013/157367 pamphlet (corresponding to compound (a) described later) was evaluated. . Compound (a) was irreversible in the second oxidation (Fig. 2) and unstable to two-electron oxidation.

Example 8 (Device evaluation of compound (A7))
The structural formulas and abbreviations of the compounds used for element evaluation are shown below.

A glass substrate laminated with an ITO transparent electrode (anode) having a thickness of 200 nm was subjected to ultrasonic cleaning with acetone and pure water and boiling cleaning with isopropyl alcohol. Furthermore, it was cleaned with ultraviolet rays/ozone, placed in a vacuum deposition apparatus, and then evacuated to 1×10 ⁻⁴ Pa by a vacuum pump. First, HIL was deposited on an ITO transparent electrode to a thickness of 55 nm at a rate of 0.15 nm/sec to form a hole injection layer, and subsequently HAT was deposited to a thickness of 5 nm at a rate of 0.05 nm/sec to form a charge generation layer. was made. Next, HTL-1 was deposited to a thickness of 15 nm at a rate of 0.15 nm/sec to prepare a first hole transport layer, and then Compound (A7) was deposited to a thickness of 50 nm at a rate of 0.15 nm/sec. , to prepare a second hole-transport layer. Next, EML-1 and EML-2 were co-deposited at a deposition rate of 0.15 nm/sec so as to have a ratio of 97:3 (mass ratio) to form a light emitting layer of 30 nm. Subsequently, ETL and Liq were co-deposited at a deposition rate of 0.15 nm/sec so as to have a ratio of 50:50 (mass ratio) to form an electron transport layer of 30 nm. Finally, a metal mask was placed perpendicular to the ITO stripes on the substrate, and a cathode was formed. The cathode was formed by depositing silver/magnesium (mass ratio 1/10) and silver in this order to 80 nm and 20 nm, respectively, to form a two-layer structure. The deposition rate of silver/magnesium was 0.5 nm/second, and the deposition rate of silver was 0.2 nm/second. As described above, an organic electroluminescence device with a light emitting area of 4 mm ² was produced, and the film thickness of each film was measured with a stylus film thickness meter (DEKTAK, manufactured by Bruker). Further, this device was sealed in a nitrogen atmosphere glove box with an oxygen and water concentration of 1 ppm or less. Sealing was performed by using a bisphenol F-type epoxy resin (manufactured by Nagase ChemteX Corporation) between the glass sealing cap and the film formation substrate (element). A direct current was applied to the organic electroluminescence device produced as described above, and the luminescence characteristics were evaluated using a luminance meter. As light emission characteristics, voltage (V) and current efficiency (cd/A) when a current density of 10 mA/cm ² was applied were measured. In addition, the device life (hr) was measured by measuring the luminance decay time during continuous lighting when the manufactured device was driven at an initial luminance of 4000 cd/m ² , and required until the luminance (cd/m ² ) decreased by 20%. time was measured. Table 1 shows the measurement results obtained. The voltage, current efficiency, and element life were expressed as relative values using the result of Comparative Example 2 described later as a reference value (100).

Example 9 (Device evaluation of compound (A9))
An organic EL device was produced in the same manner as in Example 8, except that compound (A9) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Example 10 (Device evaluation of compound (A15))
An organic EL device was produced in the same manner as in Example 8, except that compound (A15) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Example 11 (Device evaluation of compound (A79))
An organic EL device was produced in the same manner as in Example 8, except that compound (A79) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Example 12 (Device evaluation of compound (A80))
An organic EL device was produced in the same manner as in Example 8, except that compound (A80) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Example 13 (Device evaluation of compound (A199))
An organic EL device was produced in the same manner as in Example 8, except that compound (A199) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Comparative Example 2 (Device evaluation of compound (a))
An organic EL device was produced in the same manner as in Example 8, except that the following compound (a) was used instead of compound (A7). Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Comparative Example 3 (Device evaluation of compound (b))
Instead of compound (A7), compound II-001 (corresponding to compound (b) below) described on page 11 of Korean Patent Application Publication No. 10-2010-0045587 was used. An organic EL device was produced in the same manner as in Example 8. Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

Comparative Example 4 (Device evaluation of compound (c))
Same as Example 8 except that compound A-101 described on page 3 of Chinese Patent Application Publication No. 102757300 (corresponding to compound (c) below) was used instead of compound (A7). An organic EL device was produced by the method. Table 1 shows the driving voltage, current efficiency, and device life of the organic EL device, which were measured in the same manner as in Example 8.

4 is a cyclic voltammogram of compound (A79) obtained in Example 7. FIG. 2 is a cyclic voltammogram of compound (a) described in Comparative Example 1. FIG.

The triphenylene compound of the present invention can be used as a material for an organic EL device, for example, as a hole injection material, a hole transport material, or a host material for a light-emitting layer. , excellent in device efficiency and life. Furthermore, it is not only used as a hole injection material, a hole transport material, or a light emitting material for organic EL elements or electrophotographic photoreceptors, but also in the field of organic photoconductive materials such as photoelectric conversion elements, solar cells, or image sensors. It is applicable.

Claims (7)

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

(In the formula,
Ar ¹ to Ar ⁴ are each independently a monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 30 carbon atoms, or a monocyclic, linked or condensed heteroaromatic group having 3 to 20 carbon atoms group [each of these groups independently has one or more substituents selected from the group consisting of a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, and a dibenzofuranyl group; may be used].
L ¹ represents a single bond.
L ² is a single bond or a monocyclic, linked or condensed divalent aromatic hydrocarbon group having 6 to 20 carbon atoms [these groups are each independently a methyl group, an ethyl group, a 18 linear, branched or cyclic alkyl group, methoxy group, ethoxy group, linear, branched or cyclic alkoxy group having 3 to 18 carbon atoms, halogenated alkyl group having 1 to 3 carbon atoms, 1 carbon atom to 3 halogenated alkoxy groups, monocyclic, linked or condensed aryl groups of 6 to 20 carbon atoms, monocyclic, linked or condensed aryloxy groups of 6 to 18 carbon atoms, monocyclic groups of 3 to 20 carbon atoms Substitution selected from the group consisting of a ring, linked or condensed heteroaryl group, a trialkylsilyl group having 3 to 18 carbon atoms, a triarylsilyl group having 18 to 40 carbon atoms, a cyano group, a halogen atom, and a deuterium atom You may have 1 or more types of groups. ] represents.
R ¹ and R ² each independently represent a methyl group, a methoxy group, or a cyano group; n and m each independently represent an integer of 0 to 4; ) Ar ¹ to Ar ⁴ are each independently a monocyclic, linked or condensed aromatic hydrocarbon group having 6 to 20 carbon atoms, or a monocyclic, linked or condensed heteroaromatic group having 3 to 16 carbon atoms group [each of these groups independently has one or more substituents selected from the group consisting of a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, and a dibenzofuranyl group; The triphenylene compound according to claim 1, wherein the triphenylene compound is Ar ¹ to Ar ⁴ are each independently a phenyl group, a biphenylyl group, a terphenylyl group, a naphthyl group, a fluorenyl group, a phenanthryl group, a dibenzothienyl group, or a dibenzofuranyl group [these groups are each independently It may have one or more substituents selected from the group consisting of a methyl group, a phenyl group, a triphenylsilyl group, a carbazolyl group, a dibenzothienyl group, and a dibenzofuranyl group]. Item 3. The triphenylene compound according to Item 1 or 2. Ar ¹ to Ar ⁴ are each independently a phenyl group, 4-methylphenyl group, 4-(9-carbazolyl)phenyl group, dibenzothienyl group, dibenzofuranyl group, 4-(4-dibenzothienyl)phenyl group , 4-(4-dibenzofuranyl)phenyl group, biphenylyl group, terphenylyl group, naphthyl group, 9,9-dimethyl-2-fluorenyl group, 9,9-diphenyl-2-fluorenyl group or phenanthryl group 4. The triphenylene compound according to any one of claims 1 to 3. L ² is a single bond, a monocyclic ring having 6 to 14 carbon atoms, a linked or condensed divalent aromatic hydrocarbon group [these groups are each independently a methyl group, an ethyl group, a A linear, branched, or cyclic alkyl group, a methoxy group, an ethoxy group, a linear, branched, or cyclic alkoxy group having 3 to 18 carbon atoms, a halogenated alkyl group having 1 to 3 carbon atoms, 1 to 3 halogenated alkoxy group, monocyclic, linked or condensed aryl group having 6 to 20 carbon atoms, monocyclic, linked or condensed aryloxy group having 6 to 18 carbon atoms, monocyclic having 3 to 20 carbon atoms , a linked or condensed heteroaryl group, a trialkylsilyl group having 3 to 18 carbon atoms, a triarylsilyl group having 18 to 40 carbon atoms, a cyano group, a halogen atom, and a substituent selected from the group consisting of a deuterium atom You may have one or more. ] The triphenylene compound according to any one of claims 1 to 4, characterized in that: 6. The triphenylene compound according to any one of claims 1 to ⁵ , wherein L2 is a single bond, a phenylene group or a biphenylene group. A material for an organic EL device, comprising the triphenylene compound according to any one of claims 1 to 6.

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