WO2012070535A1

WO2012070535A1 - Electron transport material, and organic electroluminescent element using same

Info

Publication number: WO2012070535A1
Application number: PCT/JP2011/076815
Authority: WO
Inventors: 馬場　大輔; 洋平小野
Original assignee: Jnc株式会社
Priority date: 2010-11-25
Filing date: 2011-11-21
Publication date: 2012-05-31
Also published as: TW201229203A; JP5907069B2; TWI475091B; JPWO2012070535A1

Abstract

The compound represented by formula (1) is characterized in being stable in a thin film state even when voltage is applied, and in having a high charge- transporting capability. This compound is suitable for a charge transport material for an organic EL element, and by using this electron transport material in the electron transport layer and/or electron injection layer of an organic EL element, an organic EL element having a long life can be obtained. In formula (1), Py is pyridyl, any hydrogen of this pyridyl can be substituted by an alkyl, cycloalkyl, phenyl, 1-naphthyl, or 2-naphthyl, and the phenyl, 1-naphthyl, or 2-naphthyl can be further substituted by an alkyl or cycloalkyl; R is hydrogen, an alkyl, a cycloalkyl, or an aryl, and any hydrogen of this aryl can be substituted by an alkyl or cycloalkyl.

Description

Electron transport material and organic electroluminescent device using the same

The present invention relates to a novel electron transport material having a pyridyl group, an organic electroluminescence device using the electron transport material (hereinafter, sometimes abbreviated as an organic EL device or simply a device), and the like.

In recent years, organic EL elements have attracted attention as next-generation full-color flat panel displays, and active research has been conducted. In order to promote the practical use of organic EL elements, it is indispensable to reduce the drive voltage and extend the life of the elements, and new electron transport materials have been developed to achieve these. In particular, it is essential to lower the driving voltage and extend the life of the blue element. Patent Document 1 (Japanese Patent Application Laid-Open No. 2003-123983) discloses that an organic EL device can be driven at a low voltage by using a 2,2′-bipyridyl compound, which is a phenanthroline derivative or an analog thereof, as an electron transport material. It is stated that it can be done. However, the element characteristics (driving voltage, light emission efficiency, etc.) reported in the examples of this document are only relative values based on comparative examples, and no actual measurement values that can be judged as practical values are described. Alternatively, example of using 2,2'-bipyridyl compound to the electron transport material, non-patent document ^{1 (Proceedings of the 10 th International} Workshop on Inorganic and Organic Electroluminescence), Patent Document 2 (JP 2002-158093 JP ) And Patent Document 3 (International Publication No. 2007/86552 pamphlet). The compound described in Non-Patent Document 1 has a low Tg and is not practical. Although the compounds described in Patent Documents 2 and 3 can drive an organic EL device at a relatively low voltage, longer life is desired for practical use.

JP 2003-123983 A JP 2002-158093 A International Publication 2007/86552 Pamphlet

The present invention has been made in view of the problems of such conventional techniques. It is an object of the present invention to provide an electron transport material that contributes to extending the lifetime of an organic EL element. Furthermore, this invention makes it a subject to provide the organic EL element using this electron transport material.

As a result of intensive studies, the present inventors have found that an organic EL that can be driven with a long lifetime by using a compound of 9- (1-naphthyl) -10-phenylanthracene having a pyridyl in the electron transport layer of an organic EL device. It was found that an element was obtained, and the present invention was completed based on this finding.
Said subject is solved by each item shown below.

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

In equation (1),
Py is pyridyl, and any hydrogen of the pyridyl is substituted with alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms. 1-naphthyl optionally substituted with phenyl, alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, or alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Optionally substituted with 2-naphthyl;
R is hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, or aryl having 6 to 14 carbon atoms, and any hydrogen in the aryl is alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. Optionally substituted with 6 cycloalkyl; and
At least one hydrogen in the compound represented by the formula (1) may be replaced with deuterium.

[2] The compound according to item [1], represented by the following formula (1-1) or (1-2):

In formulas (1-1) and (1-2),
Py is pyridyl, and any hydrogen of the pyridyl is substituted with alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms. 1-naphthyl optionally substituted with phenyl, alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, or alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Optionally substituted with 2-naphthyl;
R is hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, or aryl having 6 to 14 carbon atoms, and any hydrogen in the aryl is alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. Optionally substituted with 6 cycloalkyl;
At least one hydrogen in the compound represented by the formula (1-1) or (1-2) may be replaced with deuterium.

[3] The compound according to [1] or [2], wherein Py is 2-pyridyl.

[4] The compound according to [1] or [2], wherein Py is 3-pyridyl.

[5] The compound according to [1] or [2], wherein Py is 4-pyridyl.

[6] The compound according to [1] or [2], wherein Py is one selected from the group of monovalent groups below.

[7] The following formulas (1-1-1), (1-1-2), (1-1-3), (1-1-134), (1-1-153), (1-1- 172), (1-1-191), (1-1-210), (1-1-229), (1-2-1), (1-2-153), and (1-2-172) ) The compound according to item [1] or [2], which is one selected from the group of compounds represented by:

[8] An electron transport material containing the compound according to any one of the items [1] to [7].

[9] A pair of electrodes composed of an anode and a cathode, a light emitting layer disposed between the pair of electrodes, an electron transport material according to the item [8], disposed between the cathode and the light emitting layer. An organic electroluminescent device having an electron transport layer and / or an electron injection layer containing

[10] At least one of the electron transport layer and the electron injection layer further contains at least one selected from the group consisting of a quinolinol-based metal complex, a bipyridine derivative, a phenanthroline derivative, and a borane derivative, [9] The organic electroluminescent element according to item.

[11] At least one of the electron transport layer and the electron injection layer further includes an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, or an alkaline earth. Containing at least one selected from the group consisting of metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes The organic electroluminescent device as described in the item [10].

The compound of the present invention is stable even when a voltage is applied in a thin film state and has a feature of high charge transport capability. The compound of the present invention is suitable as a charge transport material in an organic EL device. By using the compound of the present invention for an electron transport layer and / or an electron injection layer of an organic EL device, an organic EL device having a long lifetime can be obtained. By using the organic EL element of the present invention, a high-performance display device such as full-color display can be created.

Hereinafter, the present invention will be described in more detail. In the present specification, for example, a “compound represented by formula (1-1-1)” may be referred to as “compound (1-1-1)”. Other formula symbols and formula numbers are handled in the same manner.

The term “arbitrary” used in the definition of a compound may mean “can be freely selected not only by position but also by number”. For example, the expression “any hydrogen of phenyl may be substituted with alkyl having 1 to 6 carbon atoms” is not limited to “a single hydrogen may be substituted with alkyl”, It may also mean “same alkyl, or each may be replaced by a different alkyl”.
The symbols Me, Et, i-Pr, and t-Bu used in the structural formulas, chemical reaction formulas and the like in this specification represent methyl, ethyl, isopropyl, and tertiary butyl, respectively.

<Description of compound>
1st invention of this application is a compound which has a pyridyl represented by following formula (1).

In the formula (1), Py is pyridyl. Pyridyl is specifically 2-pyridyl, 3-pyridyl or 4-pyridyl. Any hydrogen in the pyridyl may be replaced by alkyl having 1 to 6 carbons, cycloalkyl having 3 to 6 carbons, phenyl, 1-naphthyl, or 2-naphthyl. Further, phenyl, 1-naphthyl and 2-naphthyl may be further substituted with alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms. R is hydrogen, alkyl having 1 to 6 carbons, cycloalkyl having 3 to 6 carbons or aryl having 6 to 14 carbons. Any hydrogen in the aryl may be replaced by alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. In addition, at least one hydrogen in the compound represented by the formula (1) may be replaced with deuterium.

In the formula (1), the position of phenyl to which pyridyl is linked may be arbitrary, but the 4-position and 3-position are preferred. That is, a preferred embodiment of the compound of formula (1) can be represented by the following formula (1-1) or (1-2).

The definitions of R and Py in the formulas (1-1) and (1-2) are the same as described above.

Examples of alkyl having 1 to 6 carbon atoms to be substituted with pyridyl in formula (1) are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, 2,2- Dimethylpropyl, n-hexyl, and isohexyl. Of these, preferred alkyls are methyl, ethyl, isopropyl, and t-butyl, with methyl and t-butyl being more preferred. Examples of cycloalkyl having 3 to 6 carbon atoms are cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. Of these, cycloalkyl is preferably cyclohexyl in view of availability of raw materials and ease of synthesis. The above examples are the same for phenyl, 1-naphthyl and 2-naphthyl substituents substituted on pyridyl, and the aryl substituents when R is aryl having 6 to 14 carbon atoms.

The position and number of the pyridyl substituents are not particularly limited. In particular, methyl may be substituted at any position of pyridyl, and the number of substitutions can be selected from 1 to the maximum 4 that can be substituted. For alkyl, cycloalkyl, phenyl, 1-naphthyl, and 2-naphthyl longer than ethyl, it is preferable to substitute the carbon adjacent to N of pyridyl in consideration of the availability of raw materials and the ease of synthesis. The number of substitution is preferably 1 to 2, more preferably 1.

In the formulas (1), (1-1) and (1-2), the position of R substituted with 1-naphthyl may be arbitrary, but the 4-position and 5-position are preferred in consideration of the availability of raw materials, The 4th position is more preferable.

Examples of the alkyl having 1 to 6 carbon atoms and the cycloalkyl having 3 to 6 carbon atoms in R include the groups exemplified as the substituent for the pyridyl. Preferred alkyl are methyl, ethyl, isopropyl, and t-butyl, with methyl and t-butyl being more preferred. Preferred cycloalkyl is cyclohexyl in consideration of availability of raw materials and ease of synthesis. Specific examples of aryl having 6 to 14 carbon atoms in R are phenyl, biphenylyl, naphthyl, and phenanthryl. When these groups have a substituent, the maximum value of the number of substituents is a chemically possible number. However, considering the availability of raw materials and the ease of synthesis, 1 to 3 is preferable. Preferred R is the following monovalent group.

Of the above groups, the following groups are more preferred.

<Specific examples of compounds>
Specific examples of the compounds of the present invention are shown by the formulas listed below, but the present invention is not limited by the disclosure of these specific structures.

<Specific Example of Compound Represented by Formula (1-1)>
Specific examples of the compound represented by the formula (1-1) are represented by the following formulas (1-1-1) to (1-1-475). Of these, preferred compounds are those represented by the formulas (1-1-1) to (1-1-57), (1-1-58), (1-1-77), (1-1-96), (1 1-115), (1-1-134), (1-1-153), (1-1-172), (1-1-191), (1-1-210), and (1- More preferred compounds are formulas (1-1-1) to (1-1-3), (1-1-58), (1-1-77), (1-1-96). ), (1-1-115), (1-1-134), (1-1-153), (1-1-172), (1-1-191), (1-1-210), And (1-1-229).

<Specific Example of Compound Represented by Formula (1-2)>
Specific examples of the compound represented by the formula (1-2) are represented by the following formulas (1-2-1) to (1-2-475). Of these, preferred compounds are those represented by the formulas (1-2-1) to (1-2-57), (1-2-58), (1-2-77), (1-2-96), (1 -2-115), (1-2-134), (1-2-153), (1-2-172), (1-2-191), (1-2-210), and (1- More preferable compounds are the formulas (1-2-1) to (1-2-3), (1-2-58), (1-2-77), (1-296). ), (1-2-115), (1-2-134), (1-2-153), (1-2-172), (1-2-191), (1-2-210), And (1-2-229).

<Method of synthesizing compounds>
The synthesis method of the compound of the present invention will be described below. The compound of the present invention can be synthesized by appropriately combining known synthesis methods that are widely used. The method for synthesizing the compound of the present invention will be described using the compound (1-1-1) as an example.

First, a method for synthesizing 9- (naphthalen-1-yl) anthracene will be described.

In reaction 1, 1-bromonaphthalene is lithiated using an organolithium reagent, or converted into a Grignard reagent using magnesium or an organomagnesium reagent, and reacted with trimethyl borate, triethyl borate, triisopropyl borate, or the like. 1-naphthaleneboronic acid ester can be synthesized. Next, 1-naphthaleneboronic acid can be synthesized by hydrolyzing the boronic ester in reaction 2.

9- (Naphthalen-1-yl) anthracene can be synthesized by coupling 1-naphthaleneboronic acid and 9-bromoanthracene in Reaction 3 in the presence of a palladium catalyst.

Further, conversely to the above-described step in which naphthalene is converted to boronic acid and subjected to the coupling reaction, a method in which anthracene is converted to boronic acid for the coupling reaction can also be used.

In reaction 4, 9-bromoanthracene is lithiated using an organolithium reagent, or converted into a Grignard reagent using magnesium or an organomagnesium reagent, and reacted with trimethyl borate, triethyl borate, triisopropyl borate, or the like. 1-naphthaleneboronic acid ester can be synthesized. Subsequently, 9-anthraceneboronic acid can be synthesized by hydrolyzing the boronic ester in Reaction 5.

9- (Naphthalen-1-yl) anthracene can also be synthesized by coupling 9-anthraceneboronic acid and 1-bromonaphthalene in the presence of a palladium catalyst in Reaction 6. The coupling of the naphthalene ring and the anthracene ring is not limited to the Suzuki coupling reaction shown in Reaction 3 and Reaction 6, but can also be performed by the Negishi coupling reaction or the like, and these conventional methods can be appropriately used depending on the situation. . Further, 9- (naphthalen-1-yl) anthracene may be a commercially available product.

Next, the process of converting the 10-position of 9- (naphthalen-1-yl) anthracene to boronic acid will be described.

In Reaction 7, the 10-position of 9- (naphthalen-1-yl) anthracene is brominated using N-bromosuccinimide. Here too, a commonly used brominating agent other than N-bromosuccinimide can be used.

In Reaction 8, 9-bromo-10- (naphthalen-1-yl) anthracene is lithiated using an organolithium reagent, or converted into a Grignard reagent using magnesium or an organomagnesium reagent, and trimethyl borate or triethyl borate. Alternatively, (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid ester can be synthesized by reacting with triisopropyl borate or the like. Furthermore, (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid can be synthesized by hydrolyzing the boronic ester in reaction 9.

Next, a method for synthesizing pyridylphenyl bromide linked to anthracene will be described.

In reaction 10, a zinc chloride complex is synthesized from 4-iodopyridine, and in reaction 11, 4- (4-bromophenyl) pyridine is synthesized by reacting the pyridine zinc chloride complex with p-bromoiodobenzene. be able to. “ZnCl ₂ · TMEDA” in the above reaction formula is a tetramethylethylenediamine complex of zinc chloride. R in RLi or RMgX represents straight-chain or branched alkyl, preferably straight-chain or branched alkyl having 1 to 4 carbon atoms. X is a halogen, and chlorine, bromine and iodine are preferably used.

Finally, the coupling reaction between anthraceneboronic acid and pyridylphenyl bromide will be described.

The compound (1-1-1) of the present invention can be synthesized by coupling the anthraceneboronic acid and pyridylphenyl bromide in the reaction 12 in the presence of a palladium catalyst.

Other compounds of the present invention can be synthesized by appropriately changing the materials used in the above reaction. For example, by using alkyl-substituted bromobenzene such as 1-bromo-4-methylnaphthalene instead of 1-bromonaphthalene in Reaction 1 or Reaction 6, a compound having an alkyl-substituted naphthyl can be synthesized.

By using 2-iodopyridine or 3-iodopyridine instead of 4-iodopyridine used in Reaction 10, a compound in which 2-pyridyl or 3-pyridyl is substituted on phenyl can be synthesized. Also, bromopyridine can be used in place of iodopyridine. By using m-bromoiodobenzene instead of p-bromoiodobenzene used in Reaction 11, a compound in which pyridyl is bonded to the 3-position of phenyl can be synthesized.

The step of coupling phenylbromopyridine with p-bromoiodobenzene or m-bromoiodobenzene is not limited to the above Negishi coupling reaction, and the Suzuki cup used in Reaction 11 depends on the types of available raw materials and reagents. A ring reaction can also be used.

In Reactions 8 to 9, the 10-position of 9- (naphthalen-1-yl) anthracene was subjected to a coupling reaction with boronic acid. However, the boronic acid ester which is the product of Reaction 8 could be used as it was for the coupling reaction. Good. Further, as in Reaction 13 above, 9-bromo-10- (naphthalen-1-yl) anthracene is lithiated using an organolithium reagent, or converted into a Grignard reagent using magnesium or an organomagnesium reagent. Synthesis of (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid ester by reaction with isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane be able to.

Also, as shown in Reaction 14, 9-bromo-10- (naphthalen-1-yl) anthracene and bis (pinacolato) diboron or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane The same (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid ester can also be synthesized by a coupling reaction using a palladium catalyst and a base. The (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid ester thus obtained can also be suitably used for the coupling reaction of Reaction 12.

The example of the Suzuki coupling reaction shown in Reaction 12 was taken as a method for coupling the anthracene part and the pyridylphenyl bromide part, which are the final steps of the synthesis. A ring reaction may be used. Furthermore, the synthesis of the compound of the present invention is not limited to the method in which the reaction of coupling the anthracene part and the phenylene part is the final step.

A pyridylphenyl bromide substituted with an alkyl group or a cycloalkyl group for linking with anthracene can be synthesized as shown in the following reactions 15 to 16. By appropriately changing the raw materials, pyridylphenyl bromides substituted with various alkyl groups or cycloalkyl groups can be synthesized.

Pyridylphenyl bromide substituted with a phenyl group can be synthesized as shown in the following reactions 17-18. Moreover, pyridylphenyl bromide substituted with various aryl groups can be synthesized by appropriately changing the raw materials.

<Reagent used in reaction>
Specific examples of the palladium catalyst used in the Suzuki coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ , [1,1′-bis (diphenylphosphino) ferrocene] dichloropalladium (II): Pd (dppf) Cl _{_{_{2, PdCl 2 [P (t}}} -Bu) 2 - (p-NMe 2 _{Ph)] 2,} and the like.

In order to accelerate the reaction, a phosphine compound may be added to these palladium compounds in some cases. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (N, N-dibutylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) ferrocene, 1,1′-bis (di-t-butylphos Fino) ferrocene, 2,2′-bis (di-t-butylphosphino) -1,1′-binaphthyl, 2-methoxy-2 ′-(di-t-butylphosphino) -1,1′-binaphthyl, or 2-dicyclohexylphosphino-2 ', 6'-dimethoxybiphenyl.

Specific examples of the base used in the reaction include sodium carbonate, potassium carbonate, cesium carbonate, sodium hydrogen carbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, sodium acetate, phosphoric acid Examples include tripotassium or potassium fluoride.

Specific examples of the solvent used in the reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, 1,4- Examples include dioxane, methanol, ethanol, cyclopentyl methyl ether, and isopropyl alcohol. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

Specific examples of the palladium catalyst used in the Negishi coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ , bis (tri-t-butylphosphino) palladium (0), or [1,1′-bis (diphenylphosphine) Fino) ferrocene] dichloropalladium (II): Pd (dppf) Cl ₂ is given.

Specific examples of the solvent used in the reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, cyclopentyl methyl ether or 1,4-dioxane. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

When the compound of the present invention is used for an electron injection layer or an electron transport layer in an organic EL device, it is stable when an electric field is applied. These represent that the compound of the present invention is excellent as an electron injecting material or an electron transporting material for an electroluminescent device. The electron injection layer mentioned here is a layer for receiving electrons from the cathode to the organic layer, and the electron transport layer is a layer for transporting the injected electrons to the light emitting layer. The electron transport layer can also serve as the electron injection layer. The material used for each layer is referred to as an electron injection material and an electron transport material.

<Description of organic EL element>
2nd invention of this application is an organic EL element containing the compound represented by Formula (1) of this invention in an electron injection layer or an electron carrying layer. The organic EL element of the present invention has a low driving voltage and high durability during driving.

Although the structure of the organic EL device of the present invention has various modes, it is basically 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. Examples of the specific configuration of the device 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, etc.

Since the compound of the present invention has high electron injecting property and electron transporting property, it can be used for an electron injecting layer or an electron transporting layer alone or in combination with other materials. The organic EL device of the present invention emits blue, green, red and white light by combining a hole injection layer, a hole transport layer, a light emitting layer, etc. using other materials with the electron transport material of the present invention. It can also be obtained.

The light-emitting material or light-emitting dopant that can be used in the organic EL device of the present invention is daylight fluorescence as described in the Polymer Society of Japan, Polymer Functional Materials Series “Optical Functional Materials”, Joint Publication (1991), P236. Materials, fluorescent brighteners, laser dyes, organic scintillators, various fluorescent analysis reagents and other luminescent materials, supervised by Koji Koji, “Organic EL materials and displays” published by CMMC (2001) P155-156 And a light emitting material of a triplet material as described in P170 to 172.

The compounds that can be used as the light emitting material or the light emitting dopant are polycyclic aromatic compounds, heteroaromatic compounds, organometallic complexes, dyes, polymer light emitting materials, styryl derivatives, aromatic amine derivatives, coumarin derivatives, borane derivatives, oxazines. Derivatives, compounds having a spiro ring, oxadiazole derivatives, fluorene derivatives and the like. Examples of the polycyclic aromatic compound are anthracene derivatives, phenanthrene derivatives, naphthacene derivatives, pyrene derivatives, chrysene derivatives, perylene derivatives, coronene derivatives, rubrene derivatives, and the like. Examples of heteroaromatic compounds are oxadiazole derivatives having a dialkylamino group or diarylamino group, pyrazoloquinoline derivatives, pyridine derivatives, pyran derivatives, phenanthroline derivatives, silole derivatives, thiophene derivatives having a triphenylamino group, quinacridone derivatives Etc. Examples of organometallic complexes are zinc, aluminum, beryllium, europium, terbium, dysprosium, iridium, platinum, osmium, gold, etc., quinolinol derivatives, benzoxazole derivatives, benzothiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, A complex with a benzimidazole derivative, a pyrrole derivative, a pyridine derivative, a phenanthroline derivative, or the like. Examples of dyes are xanthene derivatives, polymethine derivatives, porphyrin derivatives, coumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, oxobenzanthracene derivatives, carbostyril derivatives, perylene derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazoles And pigments such as derivatives. Examples of the polymer light-emitting material are polyparaphenyl vinylene derivatives, polythiophene derivatives, polyvinyl carbazole derivatives, polysilane derivatives, polyfluorene derivatives, polyparaphenylene derivatives, and the like. Examples of styryl derivatives are amine-containing styryl derivatives, styrylarylene derivatives, and the like.

Other electron transport materials used in the organic EL device of the present invention are arbitrarily selected from compounds that can be used as electron transport compounds in photoconductive materials and compounds that can be used in the electron transport layer and electron injection layer of organic EL devices. Can be used.

Specific examples of such electron transport materials include quinolinol metal complexes, 2,2′-bipyridyl derivatives, phenanthroline derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives, thiophene derivatives, triazole derivatives, thiadiazole derivatives, oxine derivatives. Metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole compounds, gallium complexes, pyrazole derivatives, perfluorinated phenylene derivatives, triazine derivatives, pyrazine derivatives, benzoquinoline derivatives, imidazopyridine derivatives, borane derivatives, and the like.

Regarding the hole injection material and the hole transport material used in the organic EL device of the present invention, in a photoconductive material, a compound conventionally used as a charge transport material for holes or a hole injection of an organic EL device is used. Any known material used for the layer and the hole transport layer can be selected and used. Specific examples thereof are carbazole derivatives, triarylamine derivatives, phthalocyanine derivatives and the like.

Each layer constituting the organic EL element of the present invention can be formed by forming a material to constitute each layer into a thin film by a method such as a vapor deposition method, a spin coat method, or a cast method. The film thickness of each layer thus formed is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. Note that it is preferable to adopt a vapor deposition method as a method of thinning the light emitting material from the viewpoint that a homogeneous film can be easily obtained and pinholes are hardly generated. When thinning using the vapor deposition method, the vapor deposition conditions differ depending on the type of the light emitting material of the present invention. Deposition conditions generally include boat heating temperature 50 to 400 ° C., vacuum degree 10 ⁻⁶ to 10 ⁻³ Pa, deposition rate 0.01 to 50 nm / second, substrate temperature −150 to + 300 ° C., film thickness 5 nm to 5 μm. It is preferable to set appropriately within the range.

The organic EL device of the present invention is preferably supported by a substrate in any of the structures described above. The substrate only needs to have mechanical strength, thermal stability, and transparency, and glass, a transparent plastic film, and the like can be used. As the anode material, metals, alloys, electrically conductive compounds and mixtures thereof having a work function larger than 4 eV can be used. Specific examples thereof include metals such as Au, CuI, indium tin oxide (hereinafter abbreviated as ITO), SnO ₂ , ZnO, and the like.

Cathode materials can use metals, alloys, electrically conductive compounds, and mixtures thereof with work functions of less than 4 eV. Specific examples thereof are aluminum, calcium, magnesium, lithium, magnesium alloy, aluminum alloy and the like. Specific examples of the alloy include aluminum / lithium fluoride, aluminum / lithium, magnesium / silver, and magnesium / indium. In order to efficiently extract light emitted from the organic EL element, it is desirable that at least one of the electrodes has a light transmittance of 10% or more. The sheet resistance as the electrode is preferably several hundred Ω / □ or less. Although the film thickness depends on the properties of the electrode material, it is usually set in the range of 10 nm to 1 μm, preferably 10 to 400 nm. Such an electrode can be produced by forming a thin film by a method such as vapor deposition or sputtering using the electrode material described above.

Next, as an example of a method for producing an organic EL device using the light emitting material of the present invention, an organic material comprising the above-mentioned anode / hole injection layer / hole transport layer / light emitting layer / electron transport material of the present invention / cathode is used. A method for creating an EL element will be described. A thin film of an anode material is formed on a suitable substrate by vapor deposition to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A light emitting layer thin film is formed thereon. On this light emitting layer, the electron transport material of this invention is vacuum-deposited, a thin film is formed, and it is set as an electron carrying layer. Furthermore, the target organic EL element is obtained by forming the thin film which consists of a substance for cathodes by a vapor deposition method, and making it a cathode. In the production of the organic EL element described above, the production order can be reversed, and the cathode, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode can be produced in this order.

When a DC voltage is applied to the organic EL device thus obtained, the anode may be applied with a positive polarity and the cathode with a negative polarity. When a voltage of about 2 to 40 V is applied, a transparent or translucent electrode is applied. Luminescence can be observed from the side (anode or cathode and both). The organic EL element also emits light when an alternating voltage is applied. The alternating current waveform to be applied may be arbitrary.

Hereinafter, the present invention will be described in more detail based on examples. First, synthesis examples of the compounds used in the examples are described below.

[Synthesis Example 1] Synthesis of Compound (1-1-1) <Synthesis of 4- (4-bromophenyl) pyridine>

149 g of 4-iodopyridine and 689 mL of THF were placed in a three-necked flask, and 400 mL of 2.0 M-isopropylmagnesium chloride THF solution was added dropwise while maintaining the temperature of the contents at 1 ° C. After completion of dropping, the mixture was stirred for 15 minutes, 202 g of zinc chloride / tetramethylethylenediamine complex was added, and the mixture was stirred at room temperature for 25 minutes. Next, 226 g of p-bromoiodobenzene and 0.34 g of tetrakis (triphenylphosphine) palladium (0) were added, and the mixture was heated to reflux for 3 hours. The reaction solution was cooled to room temperature, ethylenediaminetetraacetic acid / tetrasodium salt aqueous solution (730 g / 1.7 L) was added, and the organic layer was separated. After drying the organic layer, the desiccant was filtered off, and the solvent was distilled off under reduced pressure to obtain a crude product. This crude product was purified by silica gel column chromatography (developing solvent: toluene to toluene / ethyl acetate = 9/1 (volume ratio)) to obtain 102 g of 4- (4-bromophenyl) pyridine.

<4- (4- (10- (Naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine: Synthesis of Compound (1-1-1)>

Commercially available (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid 5.22 g, 4- (4-bromophenyl) pyridine 4.12 g, tetrakis (triphenylphosphine) palladium (0) 0 .52 g, tripotassium phosphate 6.38 g, pseudocumene 25 mL, t-butyl alcohol 5 mL, and water 1 mL were placed in a flask and stirred at reflux temperature for 16 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature and then washed with pure water. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel chromatography (developing solvent: toluene to toluene / ethyl acetate = 9/1 (volume ratio)) to give 4- (4- (10- (naphthalen-1-yl) anthracene). There were obtained 3.90 g of -9-yl) phenyl) pyridine.
¹ H-NMR (CDCl ₃ ): δ = 8.8 to 8.7 (dd, 2H), 8.1 (d, 1H), 8.0 (d, 1H), 7.9 (m, 2H) , 7.8 (d, 2H), 7.7 (m, 4H), 7.7 to 7.6 (m, 1H), 7.6 (dd, 1H), 7.5 (m, 3H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m, 3H), 7.2 (m, 1H).

Synthesis Example 2 Synthesis of Compound (1-1-2) Synthesis of 3- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl) pyridine >

3- (4-Bromophenyl) pyridine 14.0 g, bispinacolatodiboron 18.3 g, [1,1-bis (diphenylphosphino) ferrocene] dichloropalladium (II) .dichloromethane complex 1.5 g, potassium acetate 11 .8 g and cyclopentyl methyl ether (CPME) 100 mL were placed in a flask and stirred at reflux temperature for 4 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature and separated by adding water and toluene. The organic layer is concentrated, dissolved in toluene, purified by activated carbon column chromatography (developing solution: toluene), and 3- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane). -2-yl) phenyl) pyridine (15.0 g) was obtained.

<3- (4- (10- (Naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine: Synthesis of Compound (1-1-2)>

1.96 g of commercially available 9-bromo-10- (naphthalen-1-yl) anthracene, 3- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl ) 1.69 g of pyridine, 0.35 g of tetrakis (triphenylphosphine) palladium (0), 2.12 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water are placed in a flask and refluxed under a nitrogen atmosphere. Stir at temperature for 16 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 9/1 (volume ratio)). Subsequently, the obtained eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.48 g of 3- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine.
¹ H-NMR (CDCl ₃ ): δ = 9.1 (d, 1H), 8.7 (dd, 1H), 8.1 (m, 2H), 8.0 (d, 1H), 7.9 7.8 (m, 2H), 7.8 (d, 2H), 7.7 (m, 2H), 7.7 to 7.6 (m, 1H), 7.6 (m, 1H), 7.5 to 7.4 (m, 4H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m, 3H), 7.2 (m, 1H).

Synthesis Example 3 Synthesis of Compound (1-1-3) <Synthesis of 2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4.18 g of commercially available (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid, 3.37 g of commercially available 2- (4-bromophenyl) pyridine, tetrakis (triphenylphosphine) palladium (0) 0 .42 g, potassium phosphate 5.04 g, pseudocumene 30 mL, isopropyl alcohol 3 mL, and water 3 mL were placed in a flask and stirred at reflux temperature for 5 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by alumina column chromatography (developing solution: toluene). The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 3.71 g of 2- (4- (10-naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine.
¹ H-NMR (CDCl ₃ ): δ = 8.8 (m, 1H), 8.3 (m, 2H), 8.1 (d, 1H), 8.0 (d, 1H), 7.9 (M, 1H), 7.9 to 7.8 (m, 3H), 7.7 to 7.6 (m, 3H), 7.6 (m, 1H), 7.5 to 7.4 (m 3H), 7.3 (m, 3H), 7.2 (m, 4H).

[Synthesis Example 4] Synthesis of Compound (1-1-134) <Synthesis of 9- (4-methoxyphenyl) -10- (naphthalen-1-yl) anthracene>

Commercially available 9-bromo-10- (naphthalen-1-yl) anthracene 46.0 g, (4-methoxyphenyl) boronic acid 20.1 g, tetrakis (triphenylphosphine) palladium (0) 1.39 g, potassium phosphate 50 .9 g, pseudocumene 300 mL, t-butyl alcohol 60 mL, and water 12 mL were placed in a flask and stirred at reflux temperature for 8 hours under a nitrogen atmosphere. Further, 1.39 g of tetrakis (triphenylphosphine) palladium (0) was added. And stirred for 9 hours. The reaction solution was cooled to room temperature, and water was added to collect the precipitated solid. After drying, this crude product was dissolved in toluene, passed through a silica gel short column (developing solution: toluene), the solvent of the eluate was distilled off, and 9- (4-methoxyphenyl) -10- (naphthalene-1 -Yl) 46.5 g of anthracene were obtained.

45.2 g of 9- (4-methoxyphenyl) -10- (naphthalen-1-yl) anthracene, 63.8 g of pyridine hydrochloride, and 50 mL of N-methylpyrrolidone are placed in a flask and stirred at reflux temperature for 5 hours under a nitrogen atmosphere. did. The reaction solution was cooled to room temperature, and water was added to collect the precipitated solid. The crude product was washed with hot water and then with methanol and then dried to obtain 42.0 g of 4- (10- (naphthalen-1-yl) anthracen-9-yl) phenol.

8.5 g of 4- (10- (naphthalen-1-yl) anthracen-9-yl) phenol and 50 mL of dry pyridine were placed in a flask, cooled to 0 ° C. in a nitrogen atmosphere, and then trifluoromethanesulfonic anhydride with stirring. 7.28 g was slowly added, the temperature was raised to room temperature, and the mixture was further stirred for 1.5 hours. Water was added to the reaction solution, and the precipitated solid was filtered off and washed with heated isopropyl alcohol. The obtained crude product was dissolved in chloroform and filtered to remove insoluble matters. Then, isopropyl alcohol was added and the resulting precipitate was collected to give 4- (10- (naphthalen-1-yl) anthracene-9- Yl) 10.4 g of phenyltrifluoromethanesulfonate was obtained.

4- (10- (Naphthalen-1-yl) anthracen-9-yl) phenyltrifluoromethanesulfonate 7.94 g, 4.57 g bispinacolatodiboron, [1,1-bis (diphenylphosphino) ferrocene] palladium A dichloride / dichloromethane complex (0.37 g), potassium acetate (2.67 g), and cyclopentyl methyl ether (CPME) (100 mL) were placed in a flask, and the mixture was stirred at a reflux temperature for 4 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The organic layer was passed through a silica gel short column (developing solution: toluene), and then the eluate was concentrated. The precipitated solid was collected by adding heptane, and 4,4,5,5-tetramethyl-2- (4- 7.0 g of (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane was obtained.

<2-Methyl-3- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine: Synthesis of Compound (1-1-134)>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 2-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. And stirred at reflux temperature for 5 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.41 g of 2-methyl-3- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.6 (dd, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.8 (d, 2H), 7.8 To 7.7 (m, 2H), 7.7 (m, 1H), 7.6 (m, 4H), 7.5 (m, 3H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m, 5H), 2.7 (s, 3H).

Synthesis Example 5 Synthesis of Compound (1-1-153) <Synthesis of 4-methyl-3- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 4-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. And stirred at reflux temperature for 7 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 0.58 g of 4-methyl-3- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.7 (m, 1H), 8.5 (m, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.8 (M, 2H), 7.7 to 7.6 (m, 6H), 7.5 (m, 3H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m 5H), 2.5 (s, 3H).

Synthesis Example 6 Synthesis of Compound (1-1-172) <Synthesis of 3-methyl-5- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 5-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. And stirred at reflux temperature for 7.5 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.33 g of 3-methyl-5- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.7 (d, 1H), 8.5 (s, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.9 ˜7.8 (m, 3H), 7.8 (d, 2H), 7.7 (m, 2H), 7.6 (m, 1H), 7.6 (m, 1H), 7.5 ( m, 3H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m, 4H), 2.5 (s, 3H).

Synthesis Example 7 Synthesis of Compound (1-1-191) <Synthesis of 2-methyl-5- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 6-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. The mixture was stirred at reflux temperature for 9 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.21 g of 2-methyl-5- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.9 (d, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 8.0 (dd, 1H), 7.9 ˜7.8 (m, 2H), 7.8 (d, 2H), 7.7 (m, 2H), 7.6 (m, 1H), 7.6 (m, 1H), 7.5 ( m, 3H), 7.4 to 7.3 (m, 3H), 7.3 to 7.2 (m, 4H), 2.7 (s, 3H).

Synthesis Example 8 Synthesis of Compound (1-1210) <Synthesis of 2-methyl-4- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 4-bromo- A flask was charged with 0.83 g of 2-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. The mixture was stirred at reflux temperature for 9 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.20 g of 2-methyl-4- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ) δ = 8.6 (d, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.9 (m, 2H), 7.8 ( d, 2H), 7.7 (m, 2H), 7.7 to 7.6 (m, 1H), 7.6 (m, 2H), 7.5 (m, 4H), 7.4 to 7 .3 (m, 2H), 7.3 to 7.2 (m, 4H), 2.7 (s, 3H).

[Synthesis Example 9] Synthesis of Compound (1-1-229) <Synthesis of 3-methyl-4- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 4-bromo- Add 1.00 g of 3-methylpyridine hydrochloride, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water to a flask. The mixture was stirred at reflux temperature for 18 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 1.02 g of 3-methyl-4- (4- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.6 (s, 1H), 8.6 (d, 1H), 8.1 (d, 1H), 8.0 (d, 1H), 7.8 (D, 2H), 7.7 (m, 1H), 7.7 (m, 1H), 7.6 (m, 4H), 7.5 (m, 3H), 7.4 (m, 3H) 7.4-7.2 (m, 4H), 2.5 (s, 3H).

Synthesis Example 10 Synthesis of Compound (1-2-1) <Synthesis of 4- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

2.78 g of commercially available (10- (naphthalen-1-yl) anthracen-9-yl) boronic acid, 2.25 g of 4- (3-bromophenyl) pyridine, 0.28 g of tetrakis (triphenylphosphine) palladium (0) 3.39 g of potassium phosphate, 20 mL of pseudocumene, 4 mL of isopropyl alcohol, and 1 mL of water were placed in a flask and stirred at reflux temperature for 10 hours under a nitrogen atmosphere. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by alumina column chromatography (developing solution: toluene). The solvent of the eluate was distilled off under reduced pressure and recrystallized from toluene to obtain 4- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine (1.54 g).
¹ H-NMR (CDCl ₃ ): δ = 8.7 (dt, 2H), 8.1 (d, 1H), 8.0 (d, 1H), 7.9 to 7.6 (m, 10H) 7.5 (m, 3H), 7.4 to 7.3 (m, 2H), 7.3 to 7.2 (m, 4H).

Synthesis Example 11 Synthesis of Compound (1-2-153) <Synthesis of 4-methyl-3- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 4-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. And stirred at reflux temperature for 6 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The eluate was concentrated under reduced pressure and reprecipitated by adding heptane to obtain 1.06 g of 4-methyl-3- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.6 (d, 1H), 8.5 (dd, 1H), 8.1 (d, 1H), 8.0 (dd, 1H), 7.8 (D, 2H), 7.8 to 7.7 (m, 2H), 7.6 to 7.4 (m, 7H), 7.4 to 7.3 (m, 2H), 7.2 to 7 .1 (m, 5H), 2.4 (d, 3H).

Synthesis Example 12 Synthesis of Compound (1-2-172) <Synthesis of 3-methyl-5- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine>

4,4,5,5-tetramethyl-2- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) -1,3,2-dioxaborolane 2.02 g, 3-bromo- A flask was charged with 0.83 g of 4-methylpyridine, 0.14 g of tetrakis (triphenylphosphine) palladium (0), 1.70 g of potassium phosphate, 20 mL of pseudocumene, 5 mL of t-butyl alcohol, and 1 mL of water under a nitrogen atmosphere. And stirred at reflux temperature for 6 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. The solvent was distilled off under reduced pressure, and the resulting solid was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 95/5 (volume ratio)). The eluate was passed through an activated carbon short column to remove colored components. The eluate was concentrated under reduced pressure and reprecipitated by adding heptane to obtain 1.01 g of 3-methyl-5- (3- (10- (naphthalen-1-yl) anthracen-9-yl) phenyl) pyridine. It was.
¹ H-NMR (CDCl ₃ ): δ = 8.8 (d, 1H), 8.5 to 8.4 (m, 1H), 8.1 (d, 1H), 8.0 (d, 1H) 7.8-7.7 (m, 7H), 7.6 (m, 2H), 7.5 (m, 3H), 7.3 (t, 2H), 7.3-7.2 (m 4H), 2.4 (d, 3H).

By appropriately changing the raw material compound, other derivative compounds of the present invention can be synthesized by a method according to the synthesis example described above.

Hereinafter, in order to describe the present invention in more detail, examples of the organic EL device using the compound of the present invention are shown, but the present invention is not limited thereto.

The organic EL elements according to Example 1 and Comparative Example 1 were manufactured, and the driving start voltage (V) in the constant current driving test and the time (hr) for maintaining the luminance of 90% or more of the initial luminance were measured. . Hereinafter, examples and comparative examples will be described in detail.

Table 1 below shows the material configuration of each layer in the electroluminescent elements according to the manufactured Example 1 and Comparative Examples 1 and 2.

In Table 1, “HI” represents N ⁴ , N ⁴ ′ -diphenyl-N ⁴ , N ⁴ ′ -bis (9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl] -4, 4′-diamine, “NPD” is N, N′-diphenyl-N, N′-dinaphthyl-4,4′-diaminobiphenyl, and compound (A) is 9-phenyl-10- (4-phenylnaphthalene-1- Yl) anthracene, compound (B) is N ⁵ , N ⁵ , N ⁹ , N ⁹ -7,7-hexaphenyl-7H-benzo [C] fluorene-5,9-diamine, and compound (C) is 9 , 10-bis (4- (pyridin-2-yl) naphthalen-1-yl) anthracene. The chemical structure is shown below together with lithium 8-quinolinolato (Liq) used for forming the cathode.

A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Vacuum Kiko Co., Ltd.), and a molybdenum vapor deposition boat containing HI, a molybdenum vapor deposition boat containing NPD, and compound (A) are placed therein. Molybdenum vapor deposition boat, molybdenum vapor deposition boat containing compound (B), molybdenum vapor deposition boat containing compound (1-1-1), molybdenum vapor deposition boat containing Liq, silver A molybdenum vapor deposition boat and a molybdenum vapor deposition boat containing magnesium were installed.

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, first, a vapor deposition boat containing HI was heated and vapor-deposited to a film thickness of 40 nm to form a hole injection layer, and then NPD was contained. The vapor deposition boat was heated and vapor-deposited to a film thickness of 25 nm to form a hole transport layer. Next, the vapor deposition boat containing the compound (A) and the vapor deposition boat containing the compound (B) were heated at the same time and vapor-deposited to a film thickness of 25 nm to form a light emitting layer. At this time, the deposition rate was adjusted so that the weight ratio of the compound (A) to the compound (B) was about 95: 5. Next, the evaporation boat containing the compound (1-1-1) was heated and evaporated to a film thickness of 25 nm to form an electron transport layer. The deposition rate of each layer was 0.01 to 1 nm / second.

Thereafter, the evaporation boat containing Liq was heated to deposit at a deposition rate of 0.003 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, the deposition boat containing silver and the deposition boat containing magnesium are heated at the same time, and the deposition rate is set to 0.01 to 10 nm / second so that the ratio of the number of atoms of silver and magnesium is about 1: 9. The cathode was formed by vapor-depositing so as to have a film thickness of 100 nm, and an organic EL device was obtained.

When a direct current voltage was applied using the ITO electrode as the anode and the Liq / magnesium-silver alloy electrode as the cathode, blue light emission with a wavelength of about 455 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 4.23 V, and the time for maintaining a luminance of 90% or more of the initial luminance was 71 hours.

<Comparative Example 1>
An organic EL device was obtained in the same manner as in Example 1 except that the compound (1-1-1) was changed to the compound (C). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 3.73 V, and the time for maintaining a luminance of 90% or more of the initial luminance was 1 hour.

The above results are summarized in Table 2.

Furthermore, the organic EL elements according to Examples 2 to 12 and Comparative Examples 2 and 3 were manufactured, and the driving start voltage (V) in the constant current driving test and the time for holding the luminance of 90% or more of the initial value (hr), respectively. ) Was measured. Hereinafter, examples and comparative examples will be described in detail.

Table 3 below shows the material configuration of each layer in the organic EL elements according to Examples 2 to 12 and Comparative Examples 2 and 3 thus manufactured.

In Table 3, “HI” represents N ⁴ , N ^{4 ′} -diphenyl-N ⁴ , N ^{4 ′} -bis (9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl] -4, 4′-diamine, HT is N-([1,1′-biphenyl] -4-yl) -9,9-dimethyl-N- (4- (9-phenyl-9H-carbazol-3-yl) phenyl) -9H-fluoren-2-amine, compound (D) is 9- (4- (naphthalen-1-yl) phenyl) -10-phenylanthracene, compound (E) is 4,4 ′-((7,7- Diphenyl-7H-benzo [c] fluorene-5,9-diyl) bis (phenylamino)) dibenzonitrile, compound (F) is 4 ′-(4- (10- (naphthalen-2-yl) anthracene-9- Yl) phenyl) -2,2 ': 6', 2 "-tel Lysine, compound (G) is a 5- (4- (10- (naphthalene-1-yl) anthracene-9-yl) phenyl) 2,4'-bipyridine.

A 26 mm × 28 mm × 0.7 mm glass substrate (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing HI, a molybdenum vapor deposition boat containing HT, and compound (D) are placed therein. Molybdenum vapor deposition boat, molybdenum vapor deposition boat containing compound (E), molybdenum vapor deposition boat containing compound (1-1-1), molybdenum vapor deposition boat containing Liq, magnesium A molybdenum boat and a tungsten evaporation boat containing silver were installed.

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, first, the vapor deposition boat containing HI was heated to deposit to a film thickness of 40 nm to form a hole injection layer, and then HT entered. The vapor deposition boat was heated and vapor-deposited so that it might become a film thickness of 30 nm, and the positive hole transport layer was formed. Next, the vapor deposition boat containing the compound (E) and the vapor deposition boat containing the compound (F) were heated at the same time and vapor-deposited to a film thickness of 35 nm to form a light emitting layer. At this time, the deposition rate was adjusted so that the weight ratio of the compound (D) to the compound (E) was about 95: 5. Next, the vapor deposition boat containing the compound (1-1-1) and the vapor deposition boat containing Liq were heated at the same time so as to have a film thickness of 25 nm to form an electron transport layer. The deposition rate was adjusted so that the weight ratio of the compound (1-1-1) and Liq was about 1: 1. The deposition rate of each layer was 0.01 to 1 nm / second.

Thereafter, the evaporation boat containing Liq was heated to deposit at a deposition rate of 0.01 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, the boat containing magnesium and the boat containing silver are heated at the same time, and the deposition rate is adjusted between 0.1 to 10 nm / second so that the atomic ratio of silver to magnesium is 1:10. A cathode was formed by vapor deposition so as to have a film thickness of 100 nm to obtain an organic EL element.

When a direct current voltage was applied using the ITO electrode as the anode and the Liq / magnesium-silver alloy electrode as the cathode, blue light emission with a wavelength of about 450 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test starting voltage was 3.89 V, and the time for maintaining 90% or more of the initial luminance was 61 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was replaced with the compound (1-1-2). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 3.79 V, and the time for maintaining a luminance of 90% or more of the initial luminance was 60 hours.

An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-1) was changed to the compound (1-1-134). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.86 V, and the time for maintaining 90% or more of the initial luminance was 177 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was replaced with the compound (1-1-153). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.87 V, and the time for maintaining 90% or more of the initial luminance was 101 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was changed to the compound (1-1-172). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test starting voltage was 3.79 V, and the time for maintaining 90% or more of the initial luminance was 87 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was replaced with the compound (1-1-191). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.57 V, and the time for maintaining 90% or more of the initial luminance was 203 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was changed to the compound (1-1-210). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.58 V, and the time for maintaining 90% or more of the initial luminance was 172 hours.

An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-1) was changed to the compound (1-1-229). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 3.67 V, and the time for maintaining 90% or more of the initial brightness was 80 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was changed to the compound (1-2-1). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test starting voltage was 4.20 V, and the time for maintaining 90% or more of the initial luminance was 57 hours.

An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-1) was replaced with the compound (1-2-153). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.85 V, and the time for maintaining a luminance of 90% or more of the initial luminance was 62 hours.

An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-1) was replaced with the compound (1-2-172). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.65 V, and the time for maintaining a luminance of 90% or more of the initial luminance was 104 hours.

<Comparative Example 2>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-1) was changed to the compound (F). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 5.35 V, and the time for maintaining 90% or more of the initial luminance was 2 hours.

<Comparative Example 3>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-1) was changed to the compound (G). A constant current driving test was performed with an ITO electrode as an anode and a Liq / magnesium-silver alloy electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 4.20 V, and the time for maintaining the luminance of 90% or more of the initial luminance was 30 hours.

The above results are summarized in Table 4.

According to a preferred aspect of the present invention, it is possible to provide an organic electroluminescent element that improves the lifetime of the light emitting element and has an excellent balance with the driving voltage, a display device including the organic electroluminescent element, and a lighting device including the organic electroluminescent element. it can.

Claims

A compound represented by the following formula (1).

In equation (1),
Py is pyridyl, and any hydrogen of the pyridyl is substituted with alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms. 1-naphthyl optionally substituted with phenyl, alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, or alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Optionally substituted with 2-naphthyl;
R is hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, or aryl having 6 to 14 carbon atoms, and any hydrogen in the aryl is alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. Optionally substituted with 6 cycloalkyl; and
At least one hydrogen in the compound represented by the formula (1) may be replaced with deuterium.
The compound according to claim 1, which is represented by the following formula (1-1) or (1-2).

In formulas (1-1) and (1-2),
Py is pyridyl, and any hydrogen of the pyridyl is substituted with alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms. 1-naphthyl optionally substituted with phenyl, alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, or alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Optionally substituted with 2-naphthyl;
R is hydrogen, alkyl having 1 to 6 carbon atoms, cycloalkyl having 3 to 6 carbon atoms, or aryl having 6 to 14 carbon atoms, and any hydrogen in the aryl is alkyl having 1 to 6 carbon atoms or 3 to 3 carbon atoms. Optionally substituted with 6 cycloalkyl; and
At least one hydrogen in the compound represented by the formula (1-1) or (1-2) may be replaced with deuterium.
The compound according to claim 1 or 2, wherein Py is 2-pyridyl.
The compound according to claim 1 or 2, wherein Py is 3-pyridyl.
The compound according to claim 1 or 2, wherein Py is 4-pyridyl.
The compound according to claim 1 or 2, wherein Py is one selected from the group of monovalent groups below.
The following formulas (1-1-1), (1-1-2), (1-1-3), (1-1-134), (1-1-153), (1-1-172), (1-1-191), (1-1-210), (1-1-229), (1-2-1), (1-2-153), and (1-2-172) The compound according to claim 1 or 2, which is one selected from the group of compounds to be prepared.
An electron transport material comprising the compound according to any one of claims 1 to 7.
The electron transport containing the electron transport material of Claim 8 arrange | positioned between a pair of electrode which consists of an anode and a cathode, the light emitting layer arrange | positioned between this pair of electrodes, and the said cathode and this light emitting layer. An organic electroluminescent device having a layer and / or an electron injection layer.
The organic material according to claim 9, wherein at least one of the electron transport layer and the electron injection layer further contains at least one selected from the group consisting of a quinolinol-based metal complex, a bipyridine derivative, a phenanthroline derivative, and a borane derivative. Electroluminescent device.
At least one of the electron transport layer and the electron injection layer is further made of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, or an alkaline earth metal. The material contains at least one selected from the group consisting of halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes. 10. The organic electroluminescent element according to 10.