JP7095324B2 - 2-Aminocarbazole compound and its uses - Google Patents

Description

The present invention relates to a 2-aminocarbazole compound having a bis (carbazole-9-yl) phenyl group and an organic EL device using the same.

Organic EL elements featuring self-luminous light can be made thinner because they do not require the backlight used in liquid crystal panels, and because they have the advantage of flexible performance that allows the screen to be curved, they are next-generation thin. Research has been actively pursued in recent years as displays and lighting, and it has already been put into practical use in mobile phone displays and televisions.

Generally, an organic EL element has a structure in which a hole transport material, a light emitting material, and an electron transport material are laminated between an anode and a cathode, but at present, in order to achieve low power consumption and long life. , A multi-layer laminated structure in which a hole injection material, an electron injection material, a hole blocking material, etc. are inserted is the mainstream. As the hole transport material, an amine compound having an appropriate ionization potential and hole transport ability is used, and for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (hereinafter referred to as "biphenyl") is used. (Abbreviated as NPD) is known, but it cannot be said that the drive voltage, light emission efficiency and durability of the element using NPD for the hole transport layer are sufficient. Further, in recent years, the development of an organic EL element using a phosphorescent light emitting material for the light emitting layer has been promoted, and the element using phosphorescent light emitting is required to have a hole transport material having a high triplet level. NPD is not sufficient in terms of triplet level, and it has been reported that, for example, an organic EL device in which a phosphorescent material having green light emission and NPD are combined has a reduced luminous efficiency (for example, non-patented). See Document 1). From such a background, 2-aminocarbazole compounds have been reported, but the life of the organic EL device is not satisfactory (see, for example, Patent Document 1).

On the other hand, a fluorenylamine compound having a bis (carbazole-9-yl) phenyl group has been reported (see, for example, Patent Document 2). Further, as a green phosphorescent host material, a carbazole compound having a bis (9-carbazole-9-yl) phenyl group has been reported (see, for example, Patent Document 3). Further, as an aromatic compound having a bis (9-carbazole-9-yl) phenyl group, an exciton blocking material described in Patent Document 4 and a hole transporting material described in Patent Document 5 have been reported.

Japanese Unexamined Patent Publication No. 2011-001349 Japanese Unexamined Patent Publication No. 2001-039934 Korean Patent Application Publication No. 10-2011-0041727 Korean Patent Application Publication No. 10-2010-0071726 Korean Patent Application Publication No. 10-2012-0061503

Journal of Applied Physics, 2004, Vol. 95, p. 7798

The fluorenylamine compound having a 9,9-dimethyl-2-fluorenyl group described in Patent Document 2 is liable to undergo thermal decomposition due to its structure, and has a problem of affecting the yield in the vacuum deposition step at the time of manufacturing an organic EL element. was there. Therefore, it is desired to develop a hole transport material which has a high triplet level and a high heat-resistant decomposability, and further enables a low drive voltage, a high luminous efficiency, and a long life of an organic EL element.

The materials disclosed in Patent Documents 3 to 5 have a problem that they cannot exhibit sufficient performance as a hole transport material in an organic EL device due to the nature of the chemical substance.

INDUSTRIAL APPLICABILITY The present invention has higher heat resistance than a conventionally known amine compound having a bis (carbazole-9-yl) phenyl group, improves the device efficiency of an organic EL device, and remarkably improves the device life. It is an object of the present invention to provide a 2-aminocarbazole compound.

As a result of diligent studies to solve the above problems, the present inventors have shown that the 2-aminocarbazole compound represented by the following general formula (1) is remarkably superior in heat-resistant decomposition property as compared with known compounds. Further, an organic EL element using a 2-aminocarbazole compound represented by the following general formula (1) as a hole transport material exhibits higher emission efficiency than when a conventionally known material is used. However, they have found that the service life is further extended, and have completed the present invention.

That is, the present invention relates to a 2-aminocarbazole compound represented by the following general formula (1) and an organic EL device containing the compound.

(In the formula, Ar is a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, a (9-carbazolyl) phenyl group, a diphenylaminophenyl group, ( N-biphenyl-N-phenylamino) phenyl group, dibenzofuranyl group, dibenzothiophenyl group, (10-phenoxadinyl) phenyl group, or (10-phenothiazine) phenyl group. M represents a single bond or phenylene group. X represents a 1,4-phenylene group or a 1,3-phenylene group, respectively.)

Since the 2-aminocarbazole compound of the present invention has high heat-decomposability, it has the effect of improving the continuous productivity and yield of the organic EL device. Further, the 2-aminocarbazole compound of the present invention exhibits higher emission efficiency than the conventionally known 2-aminocarbazole compound when used as a hole transport layer or a hole injection layer of an organic EL device. It is possible to provide an organic EL element having a remarkably excellent element life.

Hereinafter, the present invention will be described in detail.

In the 2-aminocarbazole compound represented by the general formula (1), Ar is a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, ( 9-carbazolyl) phenyl group, diphenylaminophenyl group, (N-biphenyl-N-phenylamino) phenyl group, dibenzofuranyl group, dibenzothiophenyl group, (10-phenoxadinyl) phenyl group, or (10-phenothiadinyl) Represents a phenyl group. Among these, Ar is a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, and (9) in that it is excellent in extending the life of an organic EL element. -Carbazolyl) Phenyl group, diphenylaminophenyl group, (N-biphenyl-N-phenylamino) phenyl group, dibenzofuranyl group, or dibenzothiophenyl group is preferable, and phenyl group, naphthyl group, biphenylyl group, tar More preferably, it is a phenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, a (9-carbazolyl) phenyl group, a diphenylaminophenyl group, a dibenzofuranyl group, or a dibenzothiophenyl group.

Of these, Ar is a phenyl group, 1-naphthyl group, 2-naphthyl group, 2-biphenylyl group, 3-biphenylyl group, 4-biphenylyl group, 4- (N-biphenyl-N-phenylamino) phenyl group, It is more preferably a 2-dibenzofuranyl group, a 4-dibenzofuranyl group, a 2-dibenzothiophenyl group, or a 4-dibenzothiophenyl group, and a phenyl group, a 1-naphthyl group, a 2-naphthyl group, or a 2-. More preferably, it is a biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, a 2-dibenzofuranyl group, a 4-dibenzofuranyl group, a 2-dibenzothiophenyl group, or a 4-dibenzothiophenyl group.

Of these, Ar is a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, or a 4- (N-biphenyl-N-phenylamino) phenyl group. It is more preferably a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, or a 4-biphenylyl group.

M represents a single bond or a phenylene group. M is preferably a single bond because it is excellent in extending the life of the organic EL element.

In the 2-aminocarbazole compound represented by the general formula (1), X independently represents a 1,4-phenylene group or a 1,3-phenylene group. Of these, in terms of excellent hole transportability, X is preferably a 1,4-phenylene group in both or 1,3-phenylene groups in both, and X is a 1,4-phenylene group in both. Is more preferable. Assuming that both Xs are 1,4-phenylene groups, a carbazole compound represented by the following general formula (2) can be shown.

(In the formula, the definitions of Ar and M and their preferred ranges are the same as those described in the general formula (1).)
Hereinafter, preferred compounds are specifically exemplified with respect to the carbazole compound represented by the general formula (1), but the present invention is not limited to these compounds.

The 2-aminocarbazole compound represented by the general formula (1) of the present application is not particularly limited, but is, for example, as a light emitting host material, a hole transport material, and / or a hole injection material for an organic EL device. It can be preferably used. Since the 2-aminocarbazole compound represented by the general formula (1) of the present application has excellent hole transporting ability, the life of the organic EL device is extended when used as a hole transporting layer and / or a hole injecting layer. Can be realized.

Conventionally, as a light emitting material in a light emitting layer when the 2-aminocarbazole compound represented by the general formula (1) is used as a light emitting layer, a hole injection layer, and / or a hole transport layer of an organic EL element. Known fluorescent or phosphorescent materials used can be used. The light emitting layer may be formed of only one kind of light emitting material, or may be doped with one or more kinds of light emitting materials in the host material.

When forming the hole injection layer and / or the hole transport layer containing the 2-aminocarbazole compound represented by the general formula (1), the 2-aminocarbazole compound can be used alone or can be used alone. If necessary, two or more kinds of materials may be contained or laminated, for example, an oxide such as molybdenum oxide, 7,7,8,8-tetracyanoquinodimethane, 2,3,5,6-tetra. Known electron-accepting materials such as fluoro-7,7,8,8-tetracyanoquinodimethane and hexacyanohexazatriphenylene may be contained or laminated.

Further, the 2-aminocarbazole 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 2-aminocarbazole compound represented by the general formula (1) is used as the light emitting layer of the organic EL device, the 2-aminocarbazole compound is used alone, and is doped with a known light emitting host material. Alternatively, it can be used by doping with a known light emitting dopant.

Examples of the method for forming the hole injection layer, the hole transport layer or the light emitting layer containing the 2-aminocarbazole compound represented by the general formula (1) include a vacuum vapor deposition method, a spin coating method, a casting method and the like. A known method can be applied.

The basic structure of the organic EL device from which the effect of the present invention can be obtained 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, and some of them are included. Layers may be omitted or vice versa.

The anode and cathode of the organic EL element are connected to the power supply via an electric conductor. By applying a potential between the anode and the cathode, the organic EL element operates.

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

The organic EL element is typically overlaid on the substrate and the anode or cathode can be in contact with the substrate. The electrodes that come into contact with the substrate are called lower electrodes for convenience. Generally, the lower electrode is an anode, but the organic EL device 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 adopted as the substrate in such a case. The substrate may have a composite structure including multiple material layers.

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

The general transparent 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 seleniums 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 electroluminescence emission is confirmed only through the cathode, the transmission properties of the anode are not important and any transparent, opaque or reflective conductive material 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-injecting layer and a hole-transporting 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, and by interposing these layers between the anode and the light emitting layer, many holes are generated at a lower electric field. Holes can be injected into the light emitting layer.

In the organic EL device of the present invention, the hole transport layer and / or the hole injection layer contains the 2-aminocarbazole compound represented by the general formula (1).

The hole transport layer and / or the hole injection layer may be any of known hole transport materials and / or hole injection materials together with the 2-aminocarbazole compound represented by the general formula (1). Can be selected and used in combination.

Known hole injecting materials and hole transporting materials include, for example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted calcon derivatives, and the like. Examples thereof include oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stylben derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers, especially thiophene oligomers. As the hole injection material and the hole transport material, the above-mentioned materials can be used, but porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds, particularly aromatic tertiary amine compounds may be used. preferable.

Typical examples of the above aromatic tertiary amine compound and styrylamine compound are 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-) Trillaminophenyl) -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) Audriphenyl, N, N, N-tri (p-tolyl) amine, 4- (di-p-tolylamino) -4'-[4- (di-p-tolylamino) styryl] stilben, 4-N, N- Diphenylamino- (2-diphenylvinyl) benzene, 3-methoxy-4'-N, N-diphenylaminostillbenzene, N-phenylcarbazole, 4,4'-bis [N- (1-naphthyl) -N-phenyl Examples thereof include amino] biphenyl (NPD), 4,4', 4''-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA).

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 one-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 the organic EL device contains a phosphorescent material or a fluorescent material, and emits light as a result of the recombination of electron-hole pairs in this region.

The light emitting layer may consist of a single material containing both small molecules and polymers, but more generally it consists of a host material doped with a guest compound, the emission of which originates primarily from dopants and is optional. Can have color.

Examples of the host material of the light emitting layer include compounds having a biphenyl group, a fluorenyl group, a triphenylsilyl group, a carbazole group, a pyrenyl group, or an anthranil group. For example, DPVBi (4,4'-bis (2,2-diphenylvinyl) -1,1'-biphenyl), BCzVBi (4,4'-bis (9-ethyl-3-carbazobinylene) 1,1'-biphenyl. ), TBADN (2-talshalbutyl-9,10-di (2-naphthyl) anthracene), ADN (9,10-di (2-naphthyl) anthracene), CBP (4,4'-bis (carbazole-9) -Il) biphenyl), CDBP (4,4'-bis (carbazole-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 transport material as defined below, a hole transport 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, dicyanomethylenepyrane compound, thiopyrene compound, polymethine compound, pyrylium or thiapyrylium compound, fluorene derivative, perifuranthene derivative, indenoperylene. Derivatives, bis (azinyl) amine boron compounds, bis (azinyl) methane compounds, carbostylyl compounds and the like can be mentioned.

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

Examples of dopants are Alq ₃ (tris (8-hydroxyquinoline) aluminum), DPAVBi (4,4'-bis [4- (di-para-tolylamino) styryl] biphenyl), perylene, Ir (PPy) ₃ ( Examples thereof 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 an alkali metal complex, an alkaline earth metal complex, and an earth metal complex. Examples of the alkali metal complex, alkaline earth metal complex, or earth metal complex include 8-hydroxyquinolinate lithium (Liq), bis (8-hydroxyquinolinate) zinc, and bis (8-hydroxyquinolinate). Copper, bis (8-hydroxyquinolinate) manganese, tris (8-hydroxyquinolinate) aluminum, tris (2-methyl-8-hydroxyquinolinate) aluminum, tris (8-hydroxyquinolinate) gallium, Bis (10-hydroxybenzo [h] quinolinate) berylium, bis (10-hydroxybenzo [h] quinolinate) zinc, bis (2-methyl-8-quinolinate) chlorogallium, bis (2-methyl-8-quinolinate) ( Examples thereof include o-cresolate) gallium, bis (2-methyl-8-quinolinate) -1-naphtholate aluminum, and bis (2-methyl-8-quinolinate) -2-naphtholate gallium.

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

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

Desirable compounds for the electron injection layer include fluorenone, anthraquinodimethane, diphenoquinone, thiopyrandioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fleolenilidenemethane, anthraquinodimethane, anthron and the like. Can be mentioned. In addition, the above-mentioned 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, C, and inorganic compounds such as nitrides and oxidative nitrides can also be used.

The cathode used in the present invention can be formed from any conductive material if the emission is confirmed only through the anode. Desirable 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 mixture, rare earth metals and the like.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not construed as being limited to these Examples.

The analytical instruments and measurement methods used in this example are listed below.

[Material purity measurement (HPLC analysis)]
Measuring device: Tosoh Multi-Station LC-8020
Measurement conditions: Column Inertsil ODS-3V (4.6 mmΦ x 250 mm)
Detector UV detection (wavelength 254 nm)
Eluent Methanol / Tetrahydrofuran = 9/1 (v / v ratio)
[NMR measurement]
Measuring device: Varian Gemini200
[Mass spectrometry]
Mass spectrometer: Hitachi M-80B
Measurement method: FD-MS analysis.

Synthesis Example 1 (Synthesis of 4- (carbazole-9-yl) -N- [4- (carbazole-9-yl) phenyl] -benzeneamine)
In a 500 mL three-necked flask under a nitrogen stream, 24.20 g (74.0 mmol) of 4-bromo-N- (4-bromophenyl) benzeneamine, 25.0 g (149.5 mmol) of carbazole, sodium-tert-butoxide 17. 8 g (185.0 mmol), 150 mL of o-xylene, 166.2 mg (0.74 mmol) of palladium acetate, and 449.2 mg (2.22 mmol) of tri-tert-butylphosphine were added and stirred at 140 ° C. for 25 hours. After cooling to room temperature, 100 mL of pure water and 300 mL of toluene were added, and the organic layer was separated. After concentrating the organic layer, the residue was purified by silica gel column chromatography (toluene solvent) and recrystallization (mixed solvent of toluene and methanol), and 4- (carbazole-9-yl) -N- [4- (carbazole-). 15.9 g of a white powder of 9-yl) phenyl] -benzeneamine was isolated (yield 43.0%). From mass spectrometry (FD-MS), it was confirmed that the obtained white powder was the target compound.

Mass spectrometry (FD-MS): 499 (M +).

Synthesis Example 2 2-Chloro-9- (Synthesis of 4- (N-phenyl-N- (4-biphenyl) amino) phenyl) carbazole)
In a 100 mL three-necked flask under a nitrogen stream, 6.0 g (30.0 mmol) of 2-chlorocarbazole, 11.9 g (30.0 mmol) of 4- (N-phenyl-N- (4-biphenyl) amino) bromobenzene, 6.2 g (45.0 mmol) of potassium carbonate, 40 mL of o-xylene, 67 mg (0.30 mmol) of palladium acetate, and 212 mg (1.0 mmol) of tri (tert-butyl) phosphine were added, and the mixture was stirred at 130 ° C. for 12 hours. After cooling to room temperature, 30 mL of pure water and 30 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 (mixed solvent of toluene and hexane), and a pale yellow powder of 2-chloro-9- (4- (N-phenyl-N- (4-biphenyl) amino) phenyl) carbazole was added to 11 8.8 g (22.8 mmol) was isolated (76% yield).

From mass spectrometry (FD-MS), it was confirmed that the obtained pale yellow powder was the target compound.

Mass spectrometry (FD-MS): 520 (M +).

Example 1 (Synthesis of compound (A1))

In a 100 mL three-necked flask under a nitrogen stream, 3.89 g (7.8 mmol) of 4- (carbazole-9-yl) -N- [4- (carbazole-9-yl) phenyl] -benzeneamine obtained in Synthesis Example 1 was placed. ), 2.48 g (7.7 mmol) of 2-bromo-9-phenylcarbazole, 1.04 g (10.8 mmol) of sodium-tert-butoxide, and 17 mL of o-xylene were added to the obtained slurry-like reaction solution. 17.3 mg (0.08 mmol) of palladium acetate and 46.8 mg (0.23 mmol) of tri-tert-butylphosphine were added and stirred at 140 ° C. for 27 hours. After cooling to room temperature, 100 mL of pure water and 100 mL of toluene were added, and the organic layer was separated. After concentrating the organic layer, the residue was purified by silica gel column chromatography (toluene solvent) and recrystallization (mixed solvent of toluene, hexane, and methanol), and then sublimation purification was performed to obtain 3 white powders of compound (A1). .97 g isolated (yield 69.5%, HPLC purity 99.9%).

The compounds were identified by ¹ H-NMR measurement and ¹³ C-NMR measurement.
^{1 1} H-NMR (CDCl ₃ ); 8.16-8.11 (m, 5H), 7.60-7.54 (dd, 4H), 7.49-7.41 (m, 20H), 7. 32-7.26 (m, 7H)
¹³ C-NMR (CDCl ₃ ); 147.04, 145.73, 141.93, 141.44, 141.05, 137.48, 131.91, 129.92, 128.01, 127.52, 126 .92, 125.86, 125.64, 124.46, 123.25, 121.37, 120.31, 119.95, 119.80, 118.61, 109.78, 106.98.

Example 2 (Synthesis of compound (A2))

In a 100 mL three-necked flask under a nitrogen stream, 3.89 g (7.8 mmol) of 4- (carbazole-9-yl) -N- [4- (carbazole-9-yl) phenyl] -benzeneamine obtained in Synthesis Example 1 was placed. ), 3.07 g (7.7 mmol) of 2-bromo-9-biphenylcarbazole, 1.04 g (10.8 mmol) of sodium-tert-butoxide, and 17 mL of o-xylene were added to the obtained slurry-like reaction solution. 17.3 mg (0.08 mmol) of palladium acetate and 46.8 mg (0.23 mmol) of tri-tert-butylphosphine were added and stirred at 140 ° C. for 27 hours. After cooling to room temperature, 100 mL of pure water and 100 mL of toluene were added, and the organic layer was separated. After concentrating the organic layer, the residue was purified by silica gel column chromatography (toluene solvent) and recrystallization (mixed solvent of toluene, hexane, and methanol), and then sublimation purification was performed to obtain 5 white powders of compound (A2). .12 g isolated (yield 81.3%, HPLC purity 99.9%).

Compound identification was performed by FDMS.
FDMS (m / z); 816 (M +)
Example 3 (Synthesis of compound (A18))

In a 100 mL three-necked flask under a nitrogen stream, 3.89 g (7.8 mmol) of 4- (carbazole-9-yl) -N- [4- (carbazole-9-yl) phenyl] -benzeneamine obtained in Synthesis Example 1 was placed. ), 2.87 g (7.7 mmol) of 2-bromo-9- (2-naphthyl) carbazole, 1.04 g (10.8 mmol) of sodium-tert-butoxide, and 17 mL of o-xylene were added to obtain a slurry. 17.3 mg (0.08 mmol) of palladium acetate and 46.8 mg (0.23 mmol) of tri-tert-butylphosphine were added to the reaction solution, and the mixture was stirred at 140 ° C. for 27 hours. After cooling to room temperature, 100 mL of pure water and 100 mL of toluene were added, and the organic layer was separated. After concentrating the organic layer, the residue was purified by silica gel column chromatography (toluene solvent) and recrystallization (mixed solvent of toluene, hexane, and methanol), and then sublimation purification was performed to obtain 4 white powders of compound (A18). .76 g isolated (78.1% yield, 99.9% HPLC purity).

Compound identification was performed by FDMS.
FDMS (m / z); 790 (M +).

Example 4 (Synthesis of compound (A127))

In a 100 mL three-necked flask under a nitrogen stream, 3.89 g (7.8 mmol) of 4- (carbazole-9-yl) -N- [4- (carbazole-9-yl) phenyl] -benzeneamine obtained in Synthesis Example 1 was placed. ), 2-Chloro-9- (4- (N-phenyl-N- (4-biphenyl) amino) phenyl) carbazole obtained in Synthesis Example 2, 4.01 g (7.7 mmol), sodium-tert-butoxide 1. 04 g (10.8 mmol) and 17 mL of o-xylene were added, and 17.3 mg (0.08 mmol) of palladium acetate and 46.8 mg (0.23 mmol) of tri-tert-butylphosphine were added to the obtained slurry reaction solution. Was added and stirred at 140 ° C. for 27 hours. After cooling to room temperature, 100 mL of pure water and 100 mL of toluene were added, and the organic layer was separated. After concentrating the organic layer, the residue was purified by silica gel column chromatography (toluene solvent) and recrystallization (mixed solvent of toluene, hexane, and methanol), and then sublimation purification was performed to obtain a white powder of compound (A127). .21 g isolated (yield 81.9%, HPLC purity 99.9%).

Compound identification was performed by FDMS.

FDMS (m / z); 983 (M +).

Example 4 (Evaluation of heat resistance of compound (A1))
10 mg of compound (A1) was weighed into an ampoule and sealed with high vacuum (1 × 10 ^-3 Pa). This was heated from 50 ° C. to 350 ° C. at 5 ° C./min using a gas chromatograph oven and heated for 200 hours. As a result of analyzing the purity of the sample after heating by HPLC, no pyrolysis product was confirmed.

Comparative Example 1 (Evaluation of heat resistance of compound (a))
The following compound (a) was synthesized by the method described in Example 6 of JP-A-2001-039934, and the heat resistance was evaluated by the same method as in Example 4. As a result, a thermal decomposition product was confirmed.

Example 5 (Evaluation of element of compound (A1))
A glass substrate on which an ITO transparent electrode (anolyde) 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, after cleaning with ultraviolet rays / ozone and installing in a vacuum vapor deposition apparatus, the air was exhausted with a vacuum pump until it became 1 × 10 ^-4 Pa. First, copper phthalocyanine was vapor-deposited on an ITO transparent electrode at a vapor deposition rate of 0.1 nm / sec to form a hole injection layer of 10 nm, and subsequently, compound (A1) was vapor-deposited at a vapor deposition rate of 0.3 nm / sec at 30 nm to form holes. It was used as a transport layer. Subsequently, the phosphorescent dopant material Tris (2-phenylpyridine) iridium (Ir (ppy) ₃ ) and the host material 4,4'-bis (N-carbazolyl) biphenyl (CBP) have a weight ratio of 1:11. It was co-deposited at a vapor deposition rate of 0.25 nm / sec so as to be .5, and a light emitting layer having a vapor deposition rate of 30 nm was obtained. Next, BAlq (bis (2-methyl-8-quinolinolat) (p-phenylphenolate) aluminum) was vapor-deposited at a vapor deposition rate of 0.3 nm / sec to form a 5 nm exciton block layer, and then Alq ₃ (Tris) was further deposited. (8-Kinolinolat) aluminum) was deposited at 0.3 nm / sec to form a 45 nm electron transport layer. Subsequently, lithium-boiled lithium was deposited at a vapor deposition rate of 0.01 nm / sec for 1 nm as an electron injection layer, and aluminum was further deposited at a vapor deposition rate of 100 nm at a vapor deposition rate of 0.25 nm / sec to form a cathode. Under a nitrogen atmosphere, a glass plate for sealing was adhered 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 manufactured, and the drive voltage and current efficiency were measured. Further, a current of 6.25 mA / cm ² was applied to the element and the change with time of the luminance was measured, and the time (luminance half-life) at which the luminance became half of the initial value was investigated. The luminance half-life was evaluated as the device life. The results are shown in Table 1. The element life is expressed as a relative value with the element life (luminance half-life) of Comparative Example 1 described later as 100.

Example 6 (Evaluation of element of compound (A2))
An organic EL device was produced by the same method as in Example 5 except that the compound (A2) was used instead of the compound (A1). Table 1 shows the drive voltage, current efficiency, and element life of the organic EL element measured by the same method as in Example 5.

Example 7 (Evaluation of element of compound (A18))
An organic EL device was produced by the same method as in Example 5 except that the compound (A18) was used instead of the compound (A1). Table 1 shows the drive voltage, current efficiency, and element life of the organic EL element measured by the same method as in Example 5.

Comparative Example 2 (Evaluation of NPD element)
By the same method as in Example 5 except that NPD (4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl) obtained by sublimating and purifying a commercially available product was used instead of the compound (A1). An organic EL element was manufactured. Table 1 shows the drive voltage, current efficiency, and element life of the organic EL element measured by the same method as in Example 5.

Reference Example 1 (Evaluation of element of compound (b))
An organic EL device was produced by the same method as in Example 5 except that the following compound (b) was used instead of the compound (A1). Table 1 shows the drive voltage, current efficiency, and element life of the organic EL element measured by the same method as in Example 5.

The arylamine compound of the present invention can be used as a hole injection material, a hole transport material, or a host material for a light emitting layer of an organic EL device, and has excellent device life characteristics and a low voltage material more than conventional materials. It is expected. Further, not only as a hole injection material, a hole transport material or a light emitting material for an organic EL element or an electrophotographic photosensitive member, but also in the field of an organic photoconductive material such as a photoelectric conversion element, a solar cell, or an image sensor. It can be applied.

Claims (6)

A 2-aminocarbazole compound represented by the general formula (1).

(In the formula, Ar is a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, a (9-carbazolyl) phenyl group, a diphenylaminophenyl group, ( N-biphenyl-N-phenylamino) phenyl group, dibenzofuranyl group, dibenzothiophenyl group, (10-phenoxadinyl) phenyl group, or (10-phenothiazine) phenyl group. M represents a single bond or phenylene group. X represents a 1,4-phenylene group or a 1,3-phenylene group, respectively.) The 2-aminocarbazole compound according to claim 1, wherein X is a 1,4-phenylene group represented by the general formula (2).

The 2-aminocarbazole compound according to claim 1 or 2, wherein M is a single bond. Ar is a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, a diphenylfluorenyl group, a spirobifluorenyl group, a phenanthryl group, a (9-carbazolyl) phenyl group, a 4-diphenylaminophenyl group, a dibenzofuranyl. The 2-aminocarbazole compound according to any one of claims 1 to 3, which is a group or a dibenzothiophenyl group. That Ar is a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, or a 4- (N-biphenyl-N-phenylamino) phenyl group. The 2-aminocarbazole compound according to any one of claims 1 to 4, which is characterized. A material for an organic EL device, which comprises the 2-aminocarbazole compound according to any one of claims 1 to 5.