TWI498321B - Electron transport material and organic electroluminescent element using same - Google Patents

Description

Electron transport material and organic electroluminescent element using same

The present invention relates to a novel electron transporting material having a pyridyl group, an organic electroluminescent device using the electron transporting material (hereinafter sometimes simply referred to as an organic EL device, or simply an element).

In recent years, organic EL elements, which are next-generation full-color flat panel displays, have received attention and have been actively studied. In order to promote the practical use of the organic EL element, it is necessary to lower the driving voltage of the element and increase the service life. To achieve these goals, new electronic transport materials are being developed. In particular, it is required that the driving voltage of the blue light element is lowered and the service life is increased. It is described in the patent document 1 (JP-A-2003-123983) that a phenanthroline derivative or a 2,2'-bipyridyl compound similar thereto can be used for an electron transporting material to drive an organic EL element at a low voltage. . However, the characteristics (driving voltage, luminous efficiency, etc.) of the elements reported in the examples of this document are only relative values based on the comparative examples, and are not actual values that can be judged as practical values. Further, 2,2'-dipyridyl compound used in Examples of the electron transporting material, Nonpatent Document ^{1 (Proceedings of the 10 th International} Workshop on Inorganic and Organic Electroluminescence), Patent Document 2 (Japanese Patent Laid-Open 2002-158093 No. (Patent No.) and Patent Document 3 (International Publication No. 2007/86552). The compound described in Non-Patent Document 1 has a low Tg and is not practical. The compounds described in Patent Documents 2 and 3 can drive the organic EL element at a relatively low voltage, but it is expected to have a longer service life in order to be practical.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-123983

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2002-158093

[Patent Document 3] International Publication No. 2007/86552

[Non-patent literature]

[Patent Document ^{1] Proceedings of the 10 th International} Workshop on Inorganic and Organic Electroluminescence (2000)

The present invention has been made in view of the above problems of the prior art. An object of the present invention is to provide an electron transporting material which contributes to an increase in the service life of an organic EL device, and an organic EL device using the electron transporting material.

The present inventors have actively studied and found that a compound having a pyridyl group, a bipyridyl group, a phenylpyridyl group or a pyridylphenyl group on a naphthyl group of 9-(1-naphthyl)anthracene is used for electron transport of an organic EL device. The layer provides an organic EL element which can be driven over a long service life, and the present invention has been completed based on this finding.

The above problems are solved by the following inventions.

[1] A compound represented by the following formula (1):

In the formula (1), Py is one selected from the group consisting of the monovalent groups represented by the following formulas (2), (3), (4) and (5), and any hydrogen of the monovalent group may be a C 1 to 6 alkyl group or a C 3 to 6 cycloalkyl group;

Ar ¹ is naphthalene-1,4-diyl or naphthalene-1,5-diyl, and any hydrogen of these groups may be substituted by an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms; ² is a phenyl group or a 2-naphthyl group, and any hydrogen of these groups may be substituted by an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms.

[2] The compound according to [1] above, wherein Py is one selected from the group consisting of monovalent groups represented by formulas (2), (3) and (4).

[3] The compound according to the above [1], wherein Py is one selected from the group consisting of monovalent groups represented by the formula (2).

[4] The compound according to the above [1], wherein Py is one selected from the group consisting of monovalent groups represented by the formula (3).

[5] The compound according to the above [1], wherein Py is one selected from the group consisting of monovalent groups represented by the formula (4).

[6] The compound according to the above [1], wherein Py is one selected from the group consisting of monovalent groups represented by the formula (5).

[7] The compound according to [1] above, wherein Py is 2-pyridyl.

[8] The compound according to [1] above, wherein Py is 3-pyridyl.

[9] The compound according to [1] above, wherein Py is 4-pyridyl.

[10] The compound according to the above [1], wherein Py is one selected from the group consisting of the following monovalent groups:

[11] The compound according to the above [1], wherein Py is one selected from the group consisting of the following monovalent groups:

[12] The compound according to [1] above, which is represented by the following formulas (1-2), (1-3), (1-19), (1-20), (1-24), ( 1-48), (1-51), (1-104) or (1-1027):

[13] An electron transporting material comprising the compound according to any one of [1] to [12] above.

[14] An organic electroluminescent device comprising: a pair of electrodes including an anode and a cathode, a light-emitting layer disposed between the pair of electrodes, and disposed between the cathode and the light-emitting layer, and comprising the item as described in [13] An electron transport layer and/or an electron injection layer of the electron transport material.

[15] The organic electroluminescent device according to the above [14], wherein at least one of the electron transporting layer and the electron injecting layer further comprises a metal complex according to a quinolinol type, a bipyridine derivative At least one of the group consisting of a phenanthroline derivative and a borane derivative.

[16] The organic electroluminescent device according to the above [14], wherein at least one of the electron transporting layer and the electron injecting layer further comprises an oxide selected from an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal, or an alkali a metal halide, an alkaline earth metal oxide, an alkaline earth metal halide, a rare earth metal oxide, a rare earth metal halide, an alkali metal organic complex, an alkaline earth metal organic complex, and an organic error of a rare earth metal At least one of the group consisting of the compounds.

[Effects of the Invention]

The compound of the present invention is characterized in that it is stable even when a voltage is applied in a thin film state and has a high charge transporting ability, and is suitable as a charge transporting material in an organic EL device. The use of the compound of the present invention in an electron transport layer of an organic EL device can provide an organic EL device having a long service life. A high-performance display device such as a full-color display can be produced by using the organic EL element of the present invention.

The invention is described in more detail below. In addition, in the present specification, "the compound of the formula (1-1)" is often referred to as "compound (1-1)", and the compound of the formula (1-2) is often referred to as "compound (1-2)" . Other styles and numbers are treated in the same way.

<Description of Compounds>

The first invention of the present invention is a compound having a pyridyl group, a bipyridyl group, a phenylpyridyl group or a pyridylphenyl group on a naphthyl group of 9-(1-naphthyl)anthracene represented by the following formula (1).

In the formula (1), Py is one selected from the group consisting of monovalent groups represented by the following formulas (2), (3), (4) and (5).

The pyridyl group represented by the formula (2) is specifically 2-pyridyl, 3-pyridyl or 4-pyridyl.

The bipyridyl group represented by the formula (3) is specifically: 2,2'-bipyridyl-5-yl, 2,2'-bipyridyl-6-yl, 2,2'-bipyridin-4-yl , 2,3'-bipyridyl-5-yl, 2,3'-bipyridyl-6-yl, 2,3'-bipyridin-4-yl, 2,4'-bipyridyl-5-yl, 2 , 4'-bipyridyl-6-yl, 2,4'-bipyridin-4-yl, 3,2'-bipyridyl-6-yl, 3,2'-bipyridyl-5-yl, 3,3 '-Bipyridyl-6-yl, 3,3'-bipyridyl-5-yl, 3,4'-bipyridyl-6-yl, 3,4'-bipyridyl-5-yl, 4,2'- Bipyridin-3-yl, 4,3'-bipyridin-3-yl or 4,4'-bipyridin-3-yl. Among them, preferred are: 2,2'-bipyridyl-5-yl, 2,2'-bipyridyl-6-yl, 2,3'-bipyridyl-5-yl, 2,3'-bipyridine -6-yl, 2,4'-bipyridyl-5-yl, 2,4'-bipyridyl-6-yl, 3,2'-bipyridyl-6-yl, 3,2'-bipyridyl-5 -3,3'-bipyridyl-6-yl, 3,3'-bipyridin-5-yl, 3,4'-bipyridyl-6-yl, 3,4'-bipyridin-5-yl 4,2'-bipyridin-3-yl, 4,3'-bipyridin-3-yl and 4,4'-bipyridin-3-yl. Moreover, it is especially preferred: 2,2'-bipyridyl-5-yl, 2,2'-bipyridyl-6-yl, 2,3'-bipyridyl-5-yl, 2,3'-bipyridine -6-yl, 2,4'-bipyridyl-5-yl and 2,4'-bipyridin-6-yl.

The phenyridinyl group of the formula (4) is specifically: 3-phenylpyridin-2-yl, 4-phenylpyridin-2-yl, 5-phenylpyridin-2-yl, 6-phenylpyridine-2- , 2-phenylpyridin-3-yl, 4-phenylpyridin-3-yl, 5-phenylpyridin-3-yl, 6-phenylpyridin-3-yl, 2-phenylpyridine-4- And 3-phenylpyridin-4-yl. Among them, preferred are: 4-phenylpyridin-2-yl, 5-phenylpyridin-2-yl, 6-phenylpyridin-2-yl, 5-phenylpyridin-3-yl, 6-phenylpyridine 3-yl, 2-phenylpyridin-4-yl. More preferably: 6-phenylpyridin-2-yl, 6-phenylpyridin-3-yl, 2-phenylpyridin-4-yl.

The pyridylphenyl group represented by the formula (5) is specifically: 4-(2-pyridyl)phenyl, 4-(3-pyridyl)phenyl, 4-(4-pyridyl)phenyl, 3-(2- Pyridyl)phenyl, 3-(3-pyridyl)phenyl, 3-(4-pyridyl)phenyl, 2-(2-pyridyl)phenyl, 2-(3-pyridyl)phenyl or 2-(4-pyridyl)phenyl. Among them, preferred are: 4-(2-pyridyl)phenyl, 4-(3-pyridyl)phenyl, 4-(4-pyridyl)phenyl, 3-(2-pyridyl)phenyl , 3-(3-pyridyl)phenyl and 3-(4-pyridyl).

Any hydrogen of the monovalent group represented by the above formulas (2) to (5) may be substituted with an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms. The alkyl group having 1 to 6 carbon atoms may, for example, be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, tert-butyl, n-pentyl or iso-pentane. Base, neopentyl, tertiary pentyl, n-hexyl, 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl or 2-ethylbutyl, etc. Among these alkyl groups, a methyl group, an ethyl group, an isopropyl group or a tertiary butyl group is preferred. The cycloalkyl group having 3 to 6 carbon atoms may, for example, be cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl or dimethyl. Cyclohexyl and the like. The number of substituents which may be bonded to the above monovalent group is, for example, the maximum substitutable amount, preferably 1 to 3, more preferably 1 to 2, and even more preferably 1.

Ar ¹ is a naphthalene-1,4-diyl or naphthalene-1,5-diyl group, and any hydrogen thereof may be substituted by a C1-6 alkyl group or a C3-6 cycloalkyl group. Examples of the substituent of the monovalent group represented by the above formulas (2) to (5) are as follows for the examples of the carbon number of 1 to 6 alkyl groups and the carbon number of 3 to 6 cycloalkyl groups. The number of substituents which may be bonded to the naphthalene-1,4-diyl or naphthalene-1,5-diyl group is, for example, the maximum substitutable amount, preferably 1 to 3, more preferably 1 to 2, and 1 Especially good.

Ar ² is a phenyl group or a 2-naphthyl group, and any hydrogen thereof may be substituted by a C 1 to 6 alkyl group or a C 3 to 6 cycloalkyl group. Examples of the substituent of the monovalent group represented by the above formulas (2) to (5) are also exemplified by the examples of the carbon number of 1 to 6 alkyl groups and the carbon number of 3 to 6 cycloalkyl groups. The number of substituents which may be bonded to the phenyl group or the 2-naphthyl group is, for example, the maximum substitutable amount, preferably 1 to 3, more preferably 1 to 2, and even more preferably 1. When Ar ² is a phenyl group or a 2-naphthyl group, the position at which the above substituents are bonded may be any position, and when it is bonded to a certain position, it is preferably 4 positions in the phenyl group, and more preferably in the 2-naphthyl group. It is 6 digits.

<Specific Example of Compound>

Specific examples of the compound of the present invention are represented by the following chemical formulas, but the present invention is not limited by the disclosure of the specific structures.

Specific examples of the compound represented by the formula (1) are represented by the following formulas (1-1) to (1-205), (1-211) to (1-617), and (1-621) to (1-1032). . Preferred among these specific examples are: compounds (1-1) to (1-12), (1-19) to (1-24), (1-31) to (1-37), (1- 39), (1-40), (1-43), (1-46)~(1-51), (1-103)~(1-114), (1-121)~(1-126) , (1-134)~(1-136), (1-138)~(1-140), (1-142)~(1-144), (1-147), (1-149), ( 1-150), (1-152)~(1-154) and (1-1023)~(1-1032). More preferred are compounds (1-1) to (1-12), (1-19) to (1-24), (1-31) to (1-37), (1-39), (1- 40), (1-43), (1-48), (1-51), (1-103)~(1-114), (1-121)~(1-126), (1-134) ~(1-136), (1-138)~(1-140), (1-142)~(1-144) and (1-1023)~(1-1032). In the formula, Me, Et, i-Pr, and t-Bu are abbreviated as methyl, ethyl, isopropyl, and tertiary butyl.

<Synthesis of Compounds>

The compounds of the present invention can be synthesized by known synthetic methods. The synthesis method of the compound of the present invention will be described below by taking the compound (1-2) as an example.

First, 9-phenylindole was synthesized in the reaction 1. The bromobenzene is reacted with magnesium metal in tetrahydrofuran to form a Grignard reagent, and 9-bromoindole is reacted with the reagent in the presence of a catalyst to form 9-phenylindole. The coupling of the benzene ring and the anthracene ring is not limited to the above method, and the conventional method may be suitably employed depending on the case of the root-coupling reaction, the Suzuki coupling reaction, and the like. A commercially available product can also be used for the other 9-phenylhydrazine.

In Reaction 2, the 10-position of 9-phenylindole was brominated using N-bromosuccinimide. A common brominating agent other than N-bromosuccinimide can also be used here.

In Reaction 3, 9-bromo-10-phenylindole is lithiated using an organolithium reagent, or a magnesium or organomagnesium reagent is used as a genomic reagent to make it with trimethyl borate, triethyl borate or triisopropyl borate. The ester or the like is reacted to synthesize (10-phenylfluoren-9-yl) borate. The boronic acid ester is hydrolyzed in the reaction 4 to synthesize (10-phenylfluoren-9-yl)boronic acid.

On the other hand, in the reaction 5, a zinc chloride complex is synthesized from 3-bromopyridine, and then the zinc chloride complex of the pyridine is reacted with 1,4-dibromonaphthalene to synthesize 3-(4-). Bromophthalen-1-yl)pyridine. Further, "ZnCl ₂ ‧ TMEDA" in the above reaction formula is a tetramethylethylenediamine complex of zinc chloride. Further, in RLi or RMgX, R represents a linear or branched alkyl group, and preferably a straight chain having a carbon number of 1 to 4 or a branched alkyl group having a carbon number of 3 to 4. X is a halogen, and chlorine, bromine or iodine is preferably used.

The compound (1-2) of the present invention can be synthesized by coupling the previous hydrazine boronic acid with a naphthalene bromide in the presence of a palladium catalyst in Reaction 7.

Other compounds of the present invention can be synthesized by appropriately changing the materials used in the above reaction. For example, a compound having an alkyl-substituted phenyl group can be synthesized by using, in the reaction 1, an alkyl-substituted bromobenzene such as 4-bromotoluene instead of bromobenzene.

The 2-pyridyl or 4-pyridyl substituted compound on the naphthyl group can be synthesized by substituting 2-bromopyridine or 4-bromopyridine for the 3-bromopyridine used in the reaction 5. Iodopyridine can also be used in place of bromopyridine. A compound in which a pyridyl group is bonded to the 5-position of the naphthyl group can be synthesized by substituting 1,5-dibromonaphthalene for the 1,4-dibromonaphthalene used in the reaction 6.

A compound in which a pyridyl group, a phenylpyridyl group or a pyridylphenyl group is bonded to a naphthyl group instead of a pyridyl group can be synthesized by the following procedure using the above reaction.

The bromobipyridine, phenylbromopyridine or pyridyl bromide can be synthesized by the previous reaction 6, by coupling the rings to each other as described in a) to c) of the reaction 8. By appropriately selecting the raw materials used in the reactions, a compound in which a nitrogen atom is introduced at any position can be obtained. The zinc chloride complex is synthesized from the compound obtained above by the reaction 5, and the zinc chloride complex is reacted with 1,4-dibromonaphthalene or 1,5-dibromonaphthalene to obtain a bipyridyl group by the reaction 6. Bromophthalene of phenylpyridyl or pyridylphenyl. The target compound can be synthesized by coupling the bromine naphthalene with hydrazine boronic acid by the reaction 7.

In the step of coupling bromobipyridine, phenylbromopyridine or pyridyl bromide with 1,4-dibromonaphthalene or 1,5-dibromonaphthalene, it is not limited to the use of the above-mentioned root-shore coupling reaction, and may be obtained according to For the types of raw materials and reagents, the Suzuki coupling reaction used in Reaction 3, Reaction 4, and Reaction 7 was used.

The reaction 3 to 4 allows the 10-position of 9-phenylindole to be a boric acid for the coupling reaction, but the product borate of the reaction 3 can also be used directly for the coupling reaction. In addition, 9-bromo-10-phenylindole is lithiated using an organolithium reagent as described in the following reaction 9, or a magnesium or organomagnesium reagent is used as a genomic reagent and it is combined with a diboronic acid diborate (bis ( The above-mentioned (10-phenylfluoren-9-yl) borate can be synthesized by reacting pinacolato)diboron) or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane.

Further, as shown in Reaction 10, 9-bromo-10-phenylindole and diborazonate or 4,4,5,5-tetramethyl-1,3,2 are made with a palladium catalyst and a base. The same boronic acid (10-phenylfluoren-9-yl) ester can also be synthesized by a coupling reaction of dioxonium cyclopentane.

The (10-phenylfluoren-9-yl) borate obtained in the above manner can also be suitably used for the coupling reaction of the reaction 7.

As a method of coupling the moiety of the ruthenium to the moiety of naphthalene as the final synthesis step, the Suzuki coupling reaction shown in Reaction 7 is employed, and the root-shore coupling reaction may be used depending on the type of the raw material and the reagent which can be obtained. Further, the synthesis of the compound of the present invention is not limited to the reaction of coupling a moiety of ruthenium with a moiety of naphthalene as a final step. When a bipyridyl group, a phenylpyridinyl group or a pyridylphenyl group is bonded to a naphthalene compound of the present invention, a part of the ruthenium may be previously coupled with a portion of the dibromonaphthalene to form a zinc chloride complex and a borate ester. It is synthesized by coupling a bipyridyl group, a phenylpyridinyl group or a pyridylphenyl group of an active group such as boric acid with a bromide of naphthalene.

<Reagents used in the reaction>

Specific examples of the palladium catalyst used in the Suzuki coupling reaction are Pd(PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd(OAc) ₂ , tris(dibenzylideneacetone) dipalladium (0), and tris(2). Benzylideneacetone) dipalladium (0) chloroform complex or bis(dibenzylideneacetone)palladium (0).

In order to promote the reaction, a phosphine compound may be added to the palladium compounds as appropriate, and specific examples thereof are: tris(tertiary butyl)phosphine, tricyclohexylphosphine, 1-(N,N-dimethylaminomethyl) -2-(di-tert-butylphosphino)ferrocene, 1-(N,N-dibutylaminemethyl)-2-(di-tert-butylphosphino)ferrocene, 1-(A) Oxymethyl)-2-(di-tert-butylphosphino)ferrocene, 1,1'-bis(di-tertiary butylphosphino)ferrocene, 2,2'-bis(di-tertiary -phosphonyl)-1,1'-binaphthyl, 2-methoxy-2'-(di-tert-butylphosphino)-1,1'-binaphthyl, or 2-dicyclohexylphosphino-2 ',6'-dimethoxybiphenyl.

Specific examples of the base used in the Suzuki coupling reaction are: sodium carbonate, potassium carbonate, cesium carbonate, sodium hydrogencarbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium tertiary sodium butoxide, sodium acetate, phosphoric acid Tripotassium or potassium fluoride.

Specific examples of the solvent used in the Suzuki coupling reaction are: benzene, toluene, xylene, 1,2,4-trimethylbenzene, N,N-dimethylformamide, tetrahydrofuran, diethyl ether, tertiary butyl methyl ether, 1 , 4-dioxane, methanol, ethanol, cyclopentyl methyl ether or isopropanol, which may be appropriately selected and used singly or in combination.

Specific examples of the palladium catalyst used in the root-shore coupling reaction are: Pd(PPh ₃ ) ₄ , PdCl ₂ (PPh ₃ ) ₂ , Pd(OAc) ₂ , tris(dibenzylideneacetone) dipalladium (0), three ( Dibenzylideneacetone)dipalladium(0)chloroform complex, bis(dibenzylideneacetone)palladium(0), bis(tris-tert-butylphosphino)palladium(0), or (1,1' - bis(diphenylphosphino)ferrocene)dichloropalladium(II).

Specific examples of the solvent used in the other shore coupling reaction are: benzene, toluene, xylene, 1,2,4-trimethylbenzene, N,N-dimethylformamide, tetrahydrofuran, diethyl ether, and tert-butyl methyl ether. , cyclopentyl methyl ether or 1,4-dioxane. These solvents can be appropriately selected and used singly or as a mixed solvent.

When the compound of the present invention is used for an electron injecting layer or an electron transporting layer in an organic EL device, it is stable when an electric field is applied. This indicates that the compound of the present invention is an excellent electron injecting material or electron transporting material of an electroluminescence type element. Here, the electron injecting layer refers to a layer that receives electrons from the cathode to the organic layer: the so-called electron transporting layer refers to a layer for transporting the injected electrons to the light emitting layer. Further, the electron transport layer may also serve as an electron injection layer. The materials used for the respective layers are referred to as an electron injecting material and an electron transporting material.

<Description of Organic EL Element>

The second invention of the present invention is an organic EL device comprising the compound of the formula (1) of the present invention in an electron injecting layer or an electron transporting layer. The organic EL device of the present invention has a low driving voltage and high durability at the time of driving.

The organic EL device of the present invention has various structures, but basically has a multilayer structure in which at least a hole transport layer, a light-emitting layer, and an electron transport layer are sandwiched between an anode and a cathode. Specific examples of the components are: (1) anode/hole transport layer/light-emitting layer/electron transport layer/cathode, (2) anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/cathode, (3) Anode/hole injection layer/hole transport layer/light-emitting layer/electron transport layer/electron injection layer/cathode.

Since the compound of the present invention has high electron injectability and electron transportability, it can be used in combination with a monomer or other materials for an electron injecting layer or an electron transporting layer. The organic EL device of the present invention can also combine the electron transporting material of the present invention with a hole injecting layer, a hole transporting layer, a light emitting layer or the like using other materials to obtain blue, green, red or white light.

The luminescent material or luminescent dopant which can be used in the organic EL device of the present invention is a polymer functional material series "photofunctional material" which is edited by the Polymer Society, and the luminescent phosphor material described in P236, co-published (1991). Fluorescent materials such as fluorescent whitening agents, laser pigments, organic scintillation lamps, and various fluorescent analysis reagents, such as those described in "Organic EL Materials and Displays" (2001) P155~P156 published by Chome Corporation. A dopant material, such as a luminescent material of a triplet material described in P170 to P172.

The compounds which can be used as the luminescent material or the luminescent dopant are: polycyclic aromatic compounds, heteroaromatic compounds, organometallic complexes, pigments, polymer luminescent materials, styryl derivatives, aromatic amine derivatives, a coumarin derivative, a borane derivative, an oxazine derivative, a compound having a spiro ring, an oxadiazole derivative, an anthracene derivative, and the like. Examples of the polycyclic aromatic compound are an anthracene derivative, a phenanthrene derivative, a condensed tetraphenyl derivative, an anthracene derivative, a 1,2-benzophene derivative, an anthracene derivative, an anthracene derivative, and a red fluorescene. Ene derivatives and the like. Examples of the heteroaromatic compound are an oxadiazole derivative having a dialkylamino group or a diarylamine group, a pyrazoloquinoline derivative, a pyridine derivative, a pyran derivative, a phenanthroline derivative, and a pyrene ( A silole derivative, a thiophene derivative having a triphenylamine group, a quinacridone derivative or the like. Examples of organometallic complexes are: zinc, aluminum, ruthenium, osmium, iridium, osmium, iridium, platinum, rhodium, gold, etc. with quinolinol derivatives, benzoxazole derivatives, benzothiazole derivatives, evil A complex of an oxadiazole derivative, a thiadiazole derivative, a benzimidazole derivative, a pyrrole derivative, a pyridine derivative, a phenanthroline derivative, or the like. Examples of the pigment are: xanthene derivatives, polymethine derivatives, porphyrin derivatives, coumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiophenes A pigment such as an aryl derivative, an oxobenzopyrene derivative, a carbostyril derivative, an anthracene derivative, a benzoxazole derivative, a benzothiazole derivative, or a benzimidazole derivative. Examples of the polymer-based light-emitting material are a polyparaphenylene derivative, a polythiophene derivative, a polyvinylcarbazole derivative, a polydecane derivative, a polyfluorene derivative, a polyparaphenylene derivative, and the like. Examples of the styryl derivative are an amine-containing styryl derivative, a styryl extended aryl derivative, and the like.

The other electron transporting material used in the organic EL device of the present invention can be arbitrarily selected from those which can be used as an electron transporting compound in the photoconductive material, and which can be used for the electron transporting layer and the electron injecting layer of the organic EL device.

Specific examples of the electron transporting material include a quinoline alcohol-based metal complex, a 2,2'-bipyridyl derivative, a phenanthroline derivative, a diphenyl-p-benzoquinone derivative, an anthracene derivative, and an oxadiazole derivative. , thiophene derivative, triazole derivative, thiadiazole derivative, metal complex of oxine derivative, quinolin derivative, polymer of quinoxaline derivative, benzazole Compounds, gallium complexes, pyrazole derivatives, perfluorinated phenyl derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives, imidazopyridine derivatives, borane derivatives, etc. .

The hole injecting material and the hole transporting material used in the organic EL element of the present invention can be used as a compound for a hole transporting material or a hole injecting layer and a hole for an organic EL element in a photoconductive material. Any of the well-known compounds of the transport layer is selected and used. Specific examples of such compounds are carbazole derivatives, triarylamine derivatives, phthalocyanine derivatives and the like.

Each layer constituting the organic EL device of the present invention can be formed by forming a film of a material constituting each layer by a vapor deposition method, a spin coating method, or a casting method. The film thickness of each layer formed as described above is not particularly limited and may be appropriately set depending on the material properties, and is usually in the range of 2 to 5000 nm. Further, in the case where a homogeneous film is easily obtained and pinholes are hard to be formed, a method of thinning a light-emitting material is preferably a vapor deposition method. When the film is formed by vapor deposition, the vapor deposition conditions vary depending on the type of the light-emitting material of the present invention. The evaporation condition is usually preferably at a heating temperature of 50 to 400 ° C, a vacuum of 10 ^-6 to 10 ^-3 Pa, an evaporation rate of 0.01 to 50 nm/sec, a substrate temperature of -150 to +300 ° C, and a film thickness of 5 Set appropriately in the range of nm~5 μm.

The organic EL device of the present invention may have any of the above structures, and is preferably supported on a substrate. As long as the substrate has mechanical strength, thermal stability, and transparency, a glass, a transparent plastic film, or the like can be used. The anode material may be a metal, an alloy, a conductive compound, or a mixture thereof having a work function greater than 4 eV, and specific examples are a metal such as Au, CuI, indium tin oxide (ITO), SnO ₂ , ZnO, or the like.

The cathode material may be a metal, an alloy, a conductive compound and a mixture thereof having a work function of less than 4 eV, and specific examples are aluminum, calcium, magnesium, lithium, Magnesium alloys, aluminum alloys, etc. Specific examples of the alloy are aluminum/lithium fluoride, aluminum/lithium, magnesium/silver, magnesium/indium, and the like. For high efficiency, the light emission of the organic EL element is derived, and at least one of the electrodes transmits light The rate is ideally more than 10%. The sheet resistance of the electrode is preferably set to be several hundred Ω/□ or less. In addition, although the film thickness also depends on the nature of the electrode material, it is always 10 nm to 1 μm, preferably In the range of 10~400nm. Such an electrode can be produced by forming a thin film by vapor deposition or sputtering using the above electrode material.

Next, an organic EL device including the above anode/hole injection layer/hole transport layer/light-emitting layer/electron transport material/cathode of the present invention will be described. The production method is an example of a method of producing an organic EL element using the luminescent material of the present invention. After forming an anode on a suitable substrate by vapor deposition to form an anode material, the anode is formed on the anode. A hole injection layer and a hole transport layer film are formed thereon, and a light-emitting layer film is formed thereon. Vacuum-depositing the electron transporting material of the present invention on the light-emitting layer to form a film as an electron Transport layer. Next, a film containing a cathode material was formed as a cathode by a vapor deposition method to obtain a target organic EL device. The order of making the organic EL element can also be reversed to The order of the electrode, the electron transport layer, the light-emitting layer, the hole transport layer, the hole injection layer, and the anode is produced.

When a direct current voltage is applied to the organic EL element obtained as described above, it may be applied with a polarity in which the anode is + cathode. If voltage is applied 2~40V, it can be viewed from the transparent or translucent electrode side (anode or cathode, and both) Measure the luminescence. Further, the organic EL element emits light when an alternating voltage is applied. Further, the waveform of the applied alternating current may be an arbitrary waveform.

[Example]

The invention will now be described in more detail on the basis of examples. First, a synthesis example of the compound used in the examples will be described.

<Synthesis Example of Compound (1-2)>

Synthesis of <3-(4-bromophthalen-1-yl)pyridine

22.98 g of 3-bromonaphthalene was placed in a flask, and the inside of the flask was replaced with nitrogen, and 160 mL of dry THF was added thereto, followed by cooling in an ice bath. Drop into it The lower isopropylmagnesium chloride-THF solution (2M) was 80 mL. After the completion of the dropwise addition, the mixture was stirred for 1 hour, and then 40.32 g of zinc chloride-tetramethylethylenediamine complex was added thereto, and after further stirring for 1 hour, it was added. 62.40 g of 1,4-dibromonaphthalene and 5.04 g of tetrakis(triphenylphosphine)palladium were heated under reflux for 4 hours. The reaction solution was cooled to room temperature, and 181.60 g of ethylenediaminetetraacetic acid-tetrasodium salt was dissolved in 200 mL. An aqueous solution made of water and stirred. The organic layer was separated from the aqueous layer, and the organic layer was dried over magnesium sulfate. The crude product obtained by distilling off the solvent under reduced pressure was subjected to silica gel column chromatography ( Purification solvent: toluene-toluene/ethyl acetate = 9/1 (volume ratio) was purified, and the solvent was evaporated under reduced pressure to give 2-(4-bromonaphthalen-1-yl)pyridine 28.90 g.

Synthesis of <3-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)pyridine

11.71 g of (10-phenylfluoren-9-yl)boronic acid, 6.96 g of 3-(4-bromonaphthalen-1-yl)pyridine, 0.74 g of tetrakis(triphenylphosphine)palladium, 10.39 g of tripotassium phosphate, 1 30 mL of 2,4-trimethylbenzene, 3 mL of isopropyl alcohol, and 3 mL of water were added to the flask, and the mixture was stirred under a nitrogen atmosphere at reflux temperature for 15 hours. Further, (10-phenylfluoren-9-yl)boronic acid was directly used as a commercial product without purification. After heating, it was cooled to room temperature, and the precipitated solid component was separated by filtration, washed with pure water, and washed with ethyl acetate. The solid component was dissolved in toluene, and purified by silica gel chromatography (developing solution toluene-toluene/ethyl acetate = 9/1 (volume ratio)), followed by filtration with activated carbon (solvent toluene). The solvent was distilled off under reduced pressure to give 1-(4-(10-phenylindole-9-yl)naphthalen-1-yl)pyridine (10.00 g).

¹ H-NMR (CDCl ₃ ): δ = 9.0 (d, 1H), 8.8 (dd, 1H), 8.0 (m, 2H), 7.8 (d, 2H), 7.7 to 7.6 (m, 4H), 7.5 ( m, 2H), 7.5 (m, 4H), 7.5 (m, 1H), 7.4 to 7.3 (m, 2H), 7.3 (m, 4H).

<Synthesis Example of Compound (1-3)> <Synthesis of 1-Bromo-4-ethoxynaphthalene>

236 g of commercially available 1-ethoxynaphthalene and 400 mL of acetonitrile were placed in a flask, and 234 g of N-bromosuccinimide (NBS) was added in a powder state while cooling in an ice bath. After stirring for 2 hours, the resulting solid was separated by filtration. The solid was dissolved in toluene, filtered through silica gel, and the solvent was evaporated under reduced pressure to give br.

Synthesis of <4-ethoxynaphthalen-1-ylboronic acid>

Magnesium 34 g and THF 500 mL were placed in a flask under a nitrogen atmosphere, and a THF 500 mL solution of 1-bromo-4-ethoxynaphthalene 317 g was added dropwise over 2 hours, followed by heating under reflux for 30 minutes. The gemen reagent obtained as above was dropped with a cannula to a flask to which 157 g of trimethoxyborane and THF 500 mL were added. After the completion of the dropwise addition, the mixture was stirred for 12 hours, and 10% dilute sulfuric acid was added thereto, and the mixture was further stirred for 1 hour, and then extracted with ethyl acetate. The organic layer was washed with pure water, and the solvent was evaporated under reduced pressure. &lt;EMI ID=4.1&gt;

Synthesis of <9-(4-ethoxynaphthalen-1-yl)-10-phenylindole

Commercially available 9-bromo-10-phenylindole 40.0 g, (4-ethoxynaphthalen-1-yl)boronic acid 33.7 g, tetrakis(triphenylphosphine)palladium(0) 0.79 g, barium hydroxide octahydrate 57.6 g, 420 mL of dimethoxyethane, and 70 mL of water were added to the flask and refluxed for 4 hours. The reaction solution was cooled to room temperature, and the precipitated solid was separated by filtration and washed with methanol. The crude product was dissolved in toluene, filtered through silica gel, and then evaporated to vacuo to give 9-(4-ethoxynaphthalen-1-yl)-10-phenylindole 43.4 g.

Synthesis of <4-(10-phenylfluoren-9-yl)naphthalen-1-ol

Add 4-(4-ethoxynaphthalen-1-yl)-10-phenylindole 42.5 g, pyridine hydrochloride 116 g, N-methyl-2-pyrrolidone 50 mL to the flask at 200 °C Heat for 14 hours. The reaction solution was cooled to room temperature, and the solid precipitated with water was separated by filtration. This solid was washed with methanol and dried to give 38.5 g of 4-(10-phenylpurpur-9-yl)naphthalen-1-ol.

Synthesis of 4-(10-phenylfluoren-9-yl)naphthalen-1-yl trifluoromethanesulfonate

26.5 g of 4-(10-phenylfluoren-9-yl)naphthalen-1-ol and 300 mL of anhydrous pyridine were placed in a flask and cooled to 0 °. 24.6 g of trifluoromethanesulfonic anhydride was added thereto and stirred for 3 hours. Water was added to the reaction solution which was returned to room temperature, and the precipitate precipitated was separated by filtration, washed with water and methanol, dissolved in toluene, and filtered through silica gel. After the solvent was distilled off under reduced pressure, heptane was added, and the obtained precipitate was separated by filtration and dried to give 3,16 g of 4-(10-phenylindole-9-yl)naphthalen-1-yl trifluoromethanesulfonate.

Synthesis of <4,4,5,5-Tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane 〉

29.6 g of 4-(10-phenylfluoren-9-yl)naphthalen-1-yl trifluoromethanesulfonate, 17.1 g of diborazonate diborate, [1,1-bis(diphenylphosphino) Ferrocene] palladium dichloride methylene chloride complex 1.37 g, potassium acetate 10.0 g, and cyclopentyl methyl ether 150 mL were placed in a flask and heated under reflux for 11 hours. After the heat is completed, toluene and water are added, and the extracted organic layer is dried, concentrated, and filtered with silica gel. After removing the solvent under reduced pressure, heptane was added, and the obtained precipitate was separated by filtration and dried to give 4,4,5,5-tetramethyl-2-(4-(10-phenylindole-9-yl) Naphthyl-1-yl)-1,3,2-dioxaborolane 11.7 g.

Synthesis of <4-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)pyridine

1.0 g of 4-iodopyridine was placed in a flask, and the inside of the flask was replaced with nitrogen, and 30 mL of dry THF was added thereto, followed by cooling in an ice bath. Drop chlorine on it Isopropylmagnesium THF solution (2M) 2.8mL, and then directly stirred for 1 hour, then add zinc chloride-tetramethylethylenediamine complex 1.4g, and then stir for 1 hour, then add trifluoromethanesulfonic acid 4-( 10-phenylindole 2.4 g of 9-yl)naphthalen-1-yl ester, 0.17 g of tetrakis(triphenylphosphine)palladium(0) and 20 mL of anhydrous xylene were heated under reflux for 12 hours. The reaction solution was cooled to room temperature, and ethylenediaminetetraacetic acid-four was added. An aqueous solution of sodium salt separates the organic layer from the aqueous layer. After the organic layer was dried over magnesium sulfate, the solvent was evaporated under reduced pressure. Chromatography by gel column chromatography (developing solution: toluene~toluene/ethyl acetate) =97/3) The crude product was purified to give the crystals of 4-(4-(10-phenylindole-9-yl)naphthalen-1-yl)pyridine.

¹ H-NMR (CDCl ₃ ): δ = 8.8 (d, 2H), 8.0 (d, 1H), 7.8 (d, 2H), 7.6 to 7.5 (m, 12H), 7.3 to 7.2 (m, 6H).

<Synthesis Example of Compound (1-19)>

Synthesis of <5-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-2,2'-bipyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g , 5-bromo-2,2'-linked 1.1 g of pyridine, 0.14 g of tetrakis(triphenylphosphine)palladium(0), 1.7 g of tripotassium phosphate, 12 mL of 1,2,4-trimethylbenzene, 2 mL of tertiary butanol, and 0.5 mL of water were added to the flask under a nitrogen atmosphere. Reflux temperature Stir for 9 hours. After the completion of the heating, the mixture was cooled to room temperature, and the precipitated solid component was separated by filtration. The solid component is dissolved in toluene and chromatographed (developing solution: toluene toluene) /ethyl acetate = 95/5 (volume ratio) was purified to give 0.81 g of 5-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-2,2'-bipyridine. In addition, the 5-bromo-2,2'-bipyridine used therein is It was synthesized by the above coupling reaction.

¹ H-NMR (CDCl ₃ ): δ = 9.0 (d, 1H), 8.8 (d, 1H), 8.6 (d, 1H), 8.6 to 8.5 (d, 1H), 8.2 (dd, 1H), 8.1 ( d, 1H), 7.9 (dt, 1H), 7.8 (d, 2H), 7.7 to 7.5 (m, 9H), 7.5 (m, 1H), 7.4 to 7.2 (m, 7H).

<Synthesis Example of Compound (1-20)>

Synthesis of <5-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-2,3'-bipyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g , 1.5 g of 5-bromo-2,3'-bipyridyl, 0.14 g of tetrakis(triphenylphosphine)palladium, 1.7 g of tripotassium phosphate, 12 mL of 1,2,4-trimethylbenzene, 2 mL of tertiary butanol and 0.5 mL of water was added to the flask, and the mixture was stirred under a nitrogen atmosphere at reflux temperature for 13 hours. After heating, it was cooled to room temperature, and the precipitated solid component was separated by filtration. The solid component was dissolved in toluene, and purified by silica gel chromatography (developing solution: toluene-toluene/ethyl acetate=85/15 (volume ratio)) to give 5-(4-(10-phenylindole-9-) Base naphthalen-1-yl)-2,3'-bipyridine 0.95 g. Further, 5-bromo-2,3'-bipyridine used therein was synthesized by the above coupling reaction.

¹ H-NMR (CDCl ₃ ): δ = 9.4 (dd, 1H), 9.1 (dd, 1H), 8.8 (dd, 1H), 8.5 (dt, 1H), 8.2 (dd, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.8 (d, 2H), 7.7 to 7.5 (m, 11H), 7.4 to 7.3 (m, 6H).

<Synthesis Example of Compound (1-24)> Synthesis of <5-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-3,4'-bipyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g , 5-bromo-3,4'-bipyridyl 1.1 g, tetrakis(triphenylphosphine)palladium(0) 0.14 g, tripotassium phosphate 1.7 g, 1,2,4-trimethylbenzene 12 mL, tertiary butanol 2 mL and 0.5 mL of water were added to the flask, and the mixture was stirred under a nitrogen atmosphere at reflux temperature for 3 hours. After heating, it was cooled to room temperature, and the precipitated solid component was separated by filtration. The solid component was dissolved in toluene, and purified by silica gel chromatography (developing solution: toluene-toluene/ethyl acetate = 3/1 (volume ratio)) to give 5-(4-(10-phenylindole-9-) Base naphthalen-1-yl)-3,4'-bipyridine 1.65 g. Further, 5-bromo-3,4'-bipyridine used therein was synthesized by the above coupling reaction.

¹ H-NMR (CDCl ₃ ): δ = 9.0 (dd, 2H), 8.8 (dd, 2H), 8.3 (t, 1H), 8.0 (d, 1H), 7.8 (d, 2H), 7.7 to 7.6 ( m, 6H), 7.6 (m, 2H), 7.5 (m, 4H), 7.4 to 7.3 (m, 6H).

<Synthesis Example of Compound (1-48)> Synthesis of <4-(3-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)phenyl)pyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g , 4-(3-bromophenyl)pyridine 1.1 g, tetrakis(triphenylphosphine)palladium(0) 0.14 g, tripotassium phosphate 1.7 g, 1,2,4-trimethylbenzene 12 mL, tertiary butanol 2 0.5 mL of water and 0.5 mL of water were added to the flask, and the mixture was stirred under a nitrogen atmosphere at reflux temperature for 4 hours. After heating, it was cooled to room temperature, and water and toluene were added for liquid separation. The organic layer was dried and concentrated, and the crude product was purified by chromatography (yield: toluene toluene/ethyl acetate = 95/5 (volume ratio)) to give 4-(3-(4-(10-phenyl)蒽-9-yl)naphthalen-1-yl)phenyl)pyridine 1.36 g. Further, 4-(3-bromophenyl)pyridine used therein was synthesized by the above coupling reaction.

¹ H-NMR (CDCl ₃ ): δ = 8.7 (d, 2H), 8.1 (d, 1H), 8.0 (t, 1H), 7.8 (m, 4H), 7.7 (m, 2H), 7.7 to 7.6 ( m, 5H), 7.6~7.5 (m, 5H), 7.5~7.4 (m, 1H), 7.4~7.3 (m, 2H), 7.3~7.2 (m, 4H).

<Synthesis Example of Compound (1-51)> Synthesis of <4-(4-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)phenyl)pyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g , 1.1 g of 4-(4-bromophenyl)pyridine, 0.14 g of tetrakis(triphenylphosphine)palladium, 1.7 g of tripotassium phosphate, 12 mL of 1,2,4-trimethylbenzene, 2 mL of tertiary butanol and water 0.5 mL was added to the flask, and the mixture was stirred under a nitrogen atmosphere at reflux temperature for 3 hours. After heating, it was cooled to room temperature, and water and toluene were added for liquid separation. The organic layer was dried and concentrated, and the crude product was purified by chromatography (yield: toluene-toluene/ethyl acetate=97/3 (volume ratio)) to give 4-(4-(4-(10-phenyl)蒽-9-yl)naphthalen-1-yl)phenyl)pyridine 0.98 g. Further, 4-(4-bromophenyl)pyridine used therein was synthesized by the above coupling reaction.

¹ H-NMR (CDCl ₃ ): δ = 8.7 (dd, 2H), 8.1 (d, 1H), 7.9 to 7.8 (q, 4H), 7.8 (d, 2H), 7.7 to 7.5 (m, 11H), 7.5~7.4(m,1H), 7.4~7.2(m,6H).

<Synthesis Example of Compound (1-104)> Synthesis of <3-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolanpentan-2-yl)naphthalen-1-yl)pyridine

29.84 g of 3-(4-bromonaphthalen-1-yl)pyridine, 5.49 g of diborazonate diborate, (1,1'-bis(diphenylphosphino)ferrocene) dichloride 3.15 g of palladium(II)-dichloromethane complex, 28.03 g of potassium acetate, and 60 mL of cyclopentyl methyl ether were placed in a flask, and the mixture was heated and stirred under a nitrogen atmosphere at reflux temperature for 1.5 hours. End of heating After cooling to room temperature, it was washed with pure water. After concentration under reduced pressure, it was purified by activated carbon column chromatography (developing solvent: toluene) to give 3-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborane). - 2-yl)naphthalen-1-yl)pyridine 30 g. Further, 3-(4-bromonaphthalen-1-yl)pyridine used therein was synthesized by the above coupling reaction.

Synthesis of <3-(4-(10-(naphthalen-2-yl)fluoren-9-yl)naphthalen-1-yl)pyridine

9-bromo-10-(naphthalen-2-yl)indole 2.0 g, 3-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2- Naphthyl-1-yl)pyridine 1.1 g, tetrakis(triphenylphosphine)palladium (0) 0.14 g, tripotassium phosphate 1.7 g, 1,2,4-trimethylbenzene 12 mL, tertiary butanol 2 mL, and water 0.5 mL were added to the flask under a nitrogen atmosphere. Stir at reflux temperature for 3 hours. After the completion of the heating, the mixture was cooled to room temperature, and water and toluene were added for liquid separation. The organic layer is dried and concentrated to obtain a chromatographic method (developing solution: toluene toluene / Ethyl acetate = 97/3 (volume ratio)) The crude product was purified to give the crystals of 4-(4-(4-(10-phenylindole-9-yl)naphthalen-1-yl)phenyl)pyridine.

¹ H-NMR (CDCl ₃ ): δ = 9.0 (dd, 1H), 8.8 (dd, 1H), 8.1 to 7.9 (m, 6H), 7.8 (d, 2H), 7.7 to 7.5 (m, 9H), 7.3~7.2(m,6H).

<Synthesis Example of Compound (1-1027)>

Synthesis of <2-methyl-3-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)pyridine

4,4,5,5-tetramethyl-2-(4-(10-phenylfluoren-9-yl)naphthalen-1-yl)-1,3,2-dioxaborolane pentane 2.0 g 3-bromo-2-methylpyridyl 0.72 g of pyridine, 0.14 g of tetrakis(triphenylphosphine)palladium, 1.7 g of tripotassium phosphate, 12 mL of 1,2,4-trimethylbenzene, 2 mL of tertiary butanol and 0.5 mL of water were added to the flask under nitrogen atmosphere and reflux temperature. Stir for 8 hours. After heating, cool to room temperature. Water and toluene were added for liquid separation. The organic layer was dried and concentrated, and the crude product was purified by silica gel chromatography (eluent: toluene-toluene/ethyl acetate=9/1 (volume ratio)) to give 2-methyl-3. -(4-(10-Phenylfluoren-9-yl)naphthalen-1-yl)pyridine 1.30 g.

¹ H-NMR (CDCl ₃ ): δ = 8.7 (dd, 1H), 7.8 (m, 3H), 7.7 to 7.5 (m, 10H), 7.4 (m, 1H), 7.4 to 7.3 (m, 3H), 7.3~7.2(m,4H), 2.5(s,3H).

The other derivative compound of the present invention can be synthesized by a method according to the above synthesis example by appropriately changing the compound of the starting material.

The following examples are given to illustrate the invention in more detail, but the invention is not limited to the examples.

The electric field light-emitting elements of Example 1 and Comparative Example 1 were produced, and the driving start voltage (V) in the constant current driving test was respectively performed and the initiality was maintained. The measurement of the time (hr) of the brightness of 90% or more of the brightness. Hereinafter, examples and comparative examples will be described in detail.

The material compositions of the respective layers in the produced electroluminescent elements of Example 1 and Comparative Examples 1 and 2 are shown in Table 1 below.

In Table 1, "CuPc" is copper phthalocyanine, "NPD" is N,N'-diphenyl-N,N'-dinaphthyl-4,4'-diaminobiphenyl, and compound (A) is 9-phenyl-10-((6-[1,1';3',1"]terphenyl-5'-yl)naphthalen-2-yl)anthracene, compound (B) is N ⁵ , N ⁵ , N ⁹ ,N ⁹ -7,7-hexaphenyl-7H-benzo[c]indole-5,9-diamine, compound (C) is 5,5'-(2-phenylindole-9,10 -Diyl)di-2,2'-bipyridine, each having the following chemical structure.

[Example 1]

Polishing the ITO film having a thickness of 180 nm by sputtering to 150 nm to obtain a glass substrate of 26 mm × 28 mm × 0.7 mm (Opto Science Corporation) As a transparent support substrate. The transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Vacuum Machinery Co., Ltd.), and a molybdenum-made vapor deposition boat to which CuPc is added, a molybdenum-made vapor deposition boat to which NPD is added, and a compound (A) are added. a molybdenum vapor deposition boat, a molybdenum vapor deposition boat to which the compound (B) is added, a molybdenum vapor deposition boat to which the compound (1-2) is added, a molybdenum vapor deposition boat to which lithium fluoride is added, and There is an aluminum tungsten evaporation boat.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5×10 ⁻⁴ Pa, and the vapor deposition boat to which CuPc was added was first heated, and the hole injection layer was formed by vapor deposition to a thickness of 40 nm, and then the vapor deposition boat to which NPD was added was heated to The hole transport layer was formed by vapor deposition at a film thickness of 30 nm. Next, the vapor deposition boat to which the compound (A) was added and the vapor deposition boat to which the compound (B) was added were simultaneously heated to form a light-emitting layer by vapor deposition so as to have a film thickness of 35 nm. The vapor deposition rate was adjusted so that the weight ratio of the compound (A) to the compound (B) became about 95:5. Then, the vapor deposition boat to which the compound (1-2) was added was heated to form an electron transport layer by vapor deposition so as to have a film thickness of 15 nm. The evaporation rate of each layer is 0.01 to 1 nm/sec.

Thereafter, the vapor deposition boat to which lithium fluoride is added is heated, and vapor deposition is performed at a vapor deposition rate of 0.003 to 0.1 nm/sec in a film thickness of 1 nm, and then an aluminum vapor deposition boat is heated to a film thickness of 100 nm. The method is carried out by vapor deposition at a vapor deposition rate of 0.01 to 10 nm/sec to form a cathode, and an organic electric field light-emitting element is obtained.

The ITO electrode is used as the anode, and the lithium fluoride/aluminum electrode is used as the cathode. When a direct current voltage is applied, blue light having a wavelength of about 455 nm is obtained. Further, a constant current driving test was carried out at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.75 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 34 hours.

<Comparative Example 1>

An organic EL element was obtained in the same manner as in Example 1 except that the compound (1-2) was replaced with the compound (C). The ITO electrode was used as the anode and the lithium fluoride/aluminum electrode was used as the cathode, and the constant current driving test was carried out at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.63 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 23 hours.

The above results are summarized in Table 2.

Further, the electroluminescent light-emitting elements of Examples 2 to 10, Comparative Example 2, and Comparative Example 3 which are different from the electric field light-emitting elements of the above-described Example 1 and Comparative Example 1 were produced, and the driving start voltage (V) in the constant current driving test was performed. The measurement of the time (hr) for maintaining the luminance of the initial luminance of 90% or more.

The material compositions of the respective layers in the electroluminescent light-emitting elements of Examples 2 to 10, Comparative Example 2, and Comparative Example 3 produced are shown in Table 3 below.

In Table 3, "HI" is N ⁴ , N ⁴ '-diphenyl-N ⁴ , N ⁴ '-bis(9-phenyl-9H-carbazol-3-yl)-[1,1'-linked Benzene]-4,4'-diamine, compound (D) is 9-phenyl-10-(4-phenylnaphthalen-1-yl)anthracene, and compound (E) is 9,10-bis(4-( Pyridin-2-yl)naphthalen-1-yl)anthracene, the compound (F) is 9,10-bis(4-(pyridin-4-yl)naphthalen-1-yl)anthracene. "NPD" and the compound (B) are the same compounds as in Table 1. The chemical structure is shown below along with the 8-hydroxyquinolate lithium (Liq) used to form the cathode.

[Example 2]

The ITO film having a thickness of 180 nm was sputter-plated to 150 nm, and a glass substrate (manufactured by Opto Science Co., Ltd.) of 26 mm × 28 mm × 0.7 mm was obtained as a transparent support substrate. The transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition device (manufactured by Vacuum Machinery Co., Ltd.), and a molybdenum-made vapor deposition boat to which HI is added, a molybdenum-made vapor deposition boat to which NPD is added, and molybdenum to which compound (D) is added. a vapor deposition boat, a molybdenum vapor deposition boat to which a compound (B) is added, a molybdenum vapor deposition boat to which a compound (1-2) is added, a molybdenum vapor deposition boat to which Liq is added, and a molybdenum vapor deposition boat to which silver is added, and A molybdenum-made vapor-deposited boat is added.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5×10 ^-4 Pa, and the vapor deposition boat to which HI was added was heated first, and the hole injection layer was formed by vapor deposition to a thickness of 40 nm, and then the vapor deposition boat to which NPD was added was heated to a film thickness. The hole transport layer was formed by evaporation at 25 nm. Subsequently, the vapor deposition boat to which the compound (D) was added and the vapor deposition boat to which the compound (B) was added were simultaneously heated to form a light-emitting layer by vapor deposition at a film thickness of 25 nm. The vapor deposition rate was adjusted in such a manner that the weight ratio of the compound (D) to (B) became about 95:5. Then, the vapor deposition boat to which the compound (1-2) was added was heated to form an electron transport layer by vapor deposition so as to have a film thickness of 25 nm. The evaporation rate of each layer is 0.01~1 nm/sec.

Thereafter, the vapor deposition boat added to Liq is heated, and vapor deposition is performed at a vapor deposition rate of 0.003 to 0.1 nm/sec in a film thickness of 1 nm, and then a vapor deposition boat in which silver is added and a vapor deposition boat in which magnesium is added are heated. The evaporation rate was adjusted in such a manner that the atomic weight ratio of silver to magnesium became about 1:9. The cathode was formed by vapor deposition at a vapor deposition rate of 0.01 to 10 nm/sec in a film thickness of 100 nm to obtain an organic electric field light-emitting element.

The ITO electrode is used as the anode and the Liq/magnesium-silver alloy electrode is used as the cathode. When a direct current voltage is applied, blue light having a wavelength of about 455 nm is obtained. Further, a constant current driving test was carried out at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.38 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 106 hours.

[Example 3]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-3). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 5.24 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 110 hours.

[Example 4]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-19). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 5.55 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 81 hours.

[Example 5]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-20). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.62 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 75 hours.

[Example 6]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-24). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 6.00 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 98 hours.

[Example 7]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-48). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 3.70 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 79 hours.

[Example 8]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-51). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.90 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 112 hours.

[Example 9]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (1-104). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 3.98 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 118 hours.

[Example 10]

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced by the compound (1-1027). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 3.55 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 82 hours.

<Comparative Example 2>

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (E). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 4.08 V, and the time for maintaining the luminance of the initial luminance of 90% or more was 2 hours.

<Comparative Example 3>

An organic EL element was obtained in the same manner as in Example 2 except that the compound (1-2) was replaced with the compound (F). The ITO electrode was used as the anode and the Liq/magnesium-silver alloy electrode was used as the cathode, and a constant current driving test was performed at a current density at which an initial luminance of 2000 cd/m ² was obtained. The starting voltage of the driving test was 3.87 V, and the time for maintaining the brightness of the initial luminance of 90% or more was 30 hours.

The above results are summarized in Table 4.

[Industry Utilization]

According to a preferred aspect of the present invention, in particular, an organic electroluminescence device having an increased lifetime and a balance with a driving voltage, a display device including the organic electroluminescence device, an illumination device including the display device, and the like can be provided.

Claims (16)

A compound represented by the following formula (1): In the formula (1), Py is one selected from the group consisting of monovalent groups represented by the following formulas (2), (3), (4), and (5), and any hydrogen of the groups may have a carbon number of 1 ~6 alkyl or carbon 3 to 6 cycloalkyl substituted; Ar ¹ is naphthalene-1,4-diyl or naphthalene-1,5-diyl, and any hydrogen of these groups may be substituted by an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms; ² is a phenyl group or a 2-naphthyl group, and any hydrogen of these groups may be substituted with an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms. The compound according to claim 1, wherein Py is one selected from the group consisting of monovalent groups represented by formulas (2), (3) and (4). The compound of claim 1, wherein Py is one selected from the group consisting of monovalent groups represented by formula (2). The compound according to claim 1, wherein Py is one selected from the group consisting of monovalent groups represented by formula (3). The compound of claim 1, wherein Py is one selected from the group consisting of monovalent groups represented by formula (4). The compound according to claim 1, wherein Py is one selected from the group consisting of monovalent groups represented by formula (5). The compound of claim 1, wherein Py is 2-pyridyl. The compound of claim 1, wherein Py is 3-pyridyl. The compound of claim 1, wherein Py is 4-pyridyl. The compound of claim 1, wherein Py is one selected from the group consisting of the following monovalent groups: The compound of claim 1, wherein Py is one selected from the group consisting of the following monovalent groups: The compound according to claim 1, which is represented by the following formulas (1-2), (1-3), (1-19), (1-20), (1-24), (1- 48), (1-51), (1-104) or (1-1027): An electron transporting material comprising the compound according to any one of claims 1 to 12. An organic electroluminescent device comprising: a pair of electrodes including an anode and a cathode, a light-emitting layer disposed between the pair of electrodes, and disposed between the cathode and the light-emitting layer, and comprising the object of claim 13 An electron transport layer and/or an electron injection layer of an electron transport material. The organic electroluminescent device of claim 14, wherein at least one of the electron transport layer and the electron injecting layer further comprises a compound selected from the group consisting of a quinolol metal complex, a bipyridine derivative, and a phenanthroline. And at least one of the group consisting of a borane derivative. The organic electroluminescent device according to claim 14, wherein at least one of the electron transporting layer and the electron injecting layer further comprises an oxide selected from the group consisting of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal, and an alkali metal. Halides, alkaline earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes, and organic complexes of rare earth metals At least one of the group consisting of objects.