JP5533645B2 - Substituted ethynyl gold-cyclic alkylaminocarbene complex and organic electroluminescence device - Google Patents

Description

  The present invention relates to a substituted ethynyl gold-cyclic alkylaminocarbene complex useful as a light emitting material for an electroluminescent device (organic electroluminescent device).

In recent years, organic electroluminescence elements have attracted attention as display devices for high-performance flat color displays, but as luminescent materials, fluorescent materials that utilize light emission from excited singlets of luminescent molecules are mainly used. In order to achieve higher efficiency, phosphorescent materials that use light emitted from excited triplets have been actively developed. However, in phosphorescent organic electroluminescence devices, the emission peak maximum due to electroluminescence is realized in the deep blue region below 440 nm, which is important for completing a full color display, and the emission color is CIE (International Commission on Illumination). It is known that it is very difficult to create an element having a y-coordinate of less than 0.18 in a color system (for example, see Non-Patent Document 1).
Moreover, until now, no organic luminescence device using the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention and the metal complex as a luminescent material has been known.

Page 7 of Abstracts of Organic EL Symposium 2006

  An object of the present invention is to provide a phosphorescent organic electroluminescence device having an emission peak maximum due to electroluminescence in a deep blue region of 440 nm or less, which is important for completing a full color display, and the emission color is CIE ( It is to provide a compound useful as a light emitting material for an organic luminescence device and the like, and to realize a device having a y coordinate of less than 0.18 in a color system.

  The subject of this invention is general formula (1).

Where
L represents a cyclic alkylaminocarbene ligand;
X represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or a heterocyclic group, wherein one or more hydrogen atoms on the carbon atom of X are independently a halogen atom, an alkyl group, Cycloalkyl group, alkenyl group, aryl group, aralkyl group, alkoxy group, aryloxy group, dialkylamino group substituted with the same or different alkyl group, alkylcarbonyl group, arylcarbonyl group, alkyl mercapto group, aryl mercapto group, alkyl A sulfonyl group or an arylsulfonyl group may be substituted, and a plurality of hydrogen atoms on the carbon atom of X are independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, or the same Or a dialkylamino group substituted with a different alkyl group, Le carbonyl group, an arylcarbonyl group, alkylmercapto group, arylmercapto group, if alkylsulfonyl group or substituted with an arylsulfonyl group, bonded groups each other adjacent may form a ring,
This is solved by a substituted ethynyl gold-cyclic alkylaminocarbene complex represented by

  According to the present invention, the phosphorescent electroluminescence emission peak maximum is present in the deep blue region (410 to 440 nm) of 440 nm or less, and the emission color is less than 0.18 in the CIE (International Commission on Illumination) color system. Such an organic electroluminescence device can be realized, and a substituted ethynyl gold-cyclic alkylaminocarbene complex useful as a light-emitting material for the organic luminescence device can be provided.

It is the phosphorescence spectrum of the complex of Example 1, and the EL spectrum of the organic electroluminescent element of Example 2 and a comparative example. 2 is a structure of an organic electroluminescence element of Example 2.

[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Glass substrate 2 ITO transparent electrode 3 Hole transport layer 4 Light emitting layer 5 Hole block layer 6 Electron transport layer 7 Aluminum electrode

  The substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention is represented by the general formula (1). In the general formula (1), L represents a cyclic alkylaminocarbene ligand. X represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or a heterocyclic group.

  As said alkyl group, a C1-C10 alkyl group is preferable, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, etc. Is mentioned. In particular, an alkyl group having 1 to 6 carbon atoms is preferable. These groups include isomers thereof.

  The cycloalkyl group is preferably a cycloalkyl group having 3 to 12 carbon atoms. For example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a cyclounyl group, and the like. A decyl group, a cyclododecyl group, etc. are mentioned.

  The aryl group is preferably an aryl group having 6 to 18 carbon atoms, for example, a phenyl group, a tolyl group, a xylyl group, a biphenyl group, an indenyl group, a naphthyl group, a dimethylnaphthyl group, an anthryl group, a phenanthryl group, or a fluorenyl group. , Pyrenyl group, chrycenyl group, naphthacenyl group and the like. In particular, an aryl group having 6 to 14 carbon atoms is preferable. These groups include isomers thereof.

  The aralkyl group is preferably an aralkyl group having 7 to 20 carbon atoms, and examples thereof include a benzyl group, a naphthylmethyl group, an indenylmethyl group, and a biphenylmethyl group.

  The heterocyclic group is preferably a saturated or unsaturated cyclic group consisting of 3 to 10 ring members containing at least one heteroatom selected from N, O or S. For example, a pyrrolyl group, Examples include furyl, thienyl, indolyl, benzofuranyl, benzothiophenyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, and the like.

  One or more hydrogen atoms on the carbon atom of X are independently a halogen atom, alkyl group, cycloalkyl group, alkenyl group, aryl group, aralkyl group, alkoxy group, aryloxy group, dialkylamino group, alkyl It may be substituted with a carbonyl group, an arylcarbonyl group, an alkyl mercapto group, an aryl mercapto group, an alkylsulfonyl group or an arylsulfonyl group.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  As said alkyl group, a C1-C20, especially 1-12 alkyl group is preferable, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, nonyl Group, decyl group, undecyl group, dodecyl group and the like. In particular, an alkyl group having 1 to 6 carbon atoms is preferable. These substituents include isomers thereof.

  The cycloalkyl group is particularly preferably a cycloalkyl group having 3 to 7 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.

  The alkenyl group is preferably an alkenyl group having 2 to 20 carbon atoms, particularly 2 to 12 carbon atoms. For example, vinyl group, propenyl group, butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group. Group, undecenyl group, dodecenyl group and the like. These substituents include isomers thereof.

  The aryl group is preferably an aryl group having 6 to 20 carbon atoms, particularly 6 to 16 carbon atoms, such as a phenyl group, tolyl group, xylyl group, biphenyl group, indenyl group, naphthyl group, dimethylnaphthyl group, anthryl group, Examples thereof include a phenanthryl group, a fluorenyl group, and a pyrenyl group. These substituents include isomers thereof.

  The aralkyl group is preferably an aralkyl group having 7 to 20 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, a naphthylmethyl group, an indenylmethyl group, and a biphenylmethyl group.

  As the alkoxy group, an alkoxy group having 1 to 10 carbon atoms is particularly preferable. For example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentanoxy group, a hexanoxy group, a heptanoxy group, an octanoxy group, a nonanoxy group, a decanoxy group Etc. These substituents include isomers thereof.

  The aryloxy group is particularly preferably an aryloxy group having 6 to 14 carbon atoms, and examples thereof include a phenoxy group, a tolyloxy group, a xylyloxy group, a naphthoxy group, and a dimethylnaphthoxy group. These substituents include isomers thereof.

  The dialkylamino group is particularly preferably a dialkylamino group substituted with two identical or different groups selected from alkyl groups having 1 to 6 carbon atoms. In particular, a dimethylamino group, a diethylamino group, a dipropylamino group, etc. are mentioned. These substituents include isomers thereof.

  The alkylcarbonyl group is particularly preferably an alkylcarbonyl group having 2 to 10 carbon atoms, and examples thereof include an acetyl group, a propanoyl group, and a butanoyl group. These substituents include isomers thereof.

  The arylcarbonyl group is particularly preferably an arylcarbonyl group having 7 to 11 carbon atoms, and examples thereof include a benzoyl group, a fluorobenzoyl group, and a naphthoyl group. These substituents include isomers thereof.

  The alkyl mercapto group is preferably an alkyl mercapto group having 1 to 6 carbon atoms, and examples thereof include a methyl mercapto group, an ethyl mercapto group, a propyl mercapto group, a butyl mercapto group, a pentyl mercapto group, and a hexyl mercapto group. These substituents include isomers thereof.

  The aryl mercapto group is preferably an aryl mercapto group having 6 to 14 carbon atoms, and examples thereof include a phenyl mercapto group, a tolyl mercapto group, a xylyl mercapto group, and a naphthyl mercapto group. These substituents include isomers thereof.

  As said alkylsulfonyl group, a C1-C12 alkylsulfonyl group is preferable, for example, a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group etc. are mentioned.

  The arylsulfonyl group is preferably an arylsulfonyl group having 6 to 18 carbon atoms, and examples thereof include a phenylsulfonyl group, a tolylsulfonyl group, and a naphthylsulfonyl group.

  A plurality of hydrogen atoms on the carbon atom of X are alkyl group, alkenyl group, aryl group, aralkyl group, alkoxy group, aryloxy group, dialkylamino group, alkylcarbonyl group and arylcarbonyl group, alkyl mercapto group, aryl mercapto group When substituted with an alkylsulfonyl group or arylsulfonyl group, adjacent substituents may be bonded to form a ring.

  For example, when two adjacent hydrogen atoms on the carbon atom of X are each independently substituted with the substituent, the adjacent substituents are carbon atoms to which they are bonded. Together with the atoms, 5-, 6- or 7-membered monocyclic or 8-, 9- or 10-membered bicyclic saturated or unsaturated ring (this is optionally included in the substituent) A heteroatom selected from O, N and S may be included.).

  Examples of the ring in the case where the adjacent groups are bonded to form a ring include, for example, a cyclopentene ring, cyclohexene ring, cycloheptene ring, benzene ring, naphthalene ring, tetrahydrofuran ring, benzopyran ring, N-methylpyrrolidine ring, N-methyl piperidine ring etc. are mentioned.

  Among these, X is selected from an alkyl group having 1 to 6 carbon atoms and an aryl group having 6 to 18 carbon atoms, and one or more hydrogen atoms on the carbon atom of X are Independently, fluorine atom, chlorine atom, bromine atom, iodine atom, dimethylamino group, diethylamino group, dipropylamino group, acetyl group, propanoyl group, butanoyl group, benzoyl group, fluorobenzoyl group, naphthoyl group, methyl mercapto group , An ethyl mercapto group, a propyl mercapto group, a methylsulfonyl group, an ethylsulfonyl group, and a propylsulfonyl group, which may be substituted with a group.

  The cyclic alkylaminocarbene ligand has the general formula (2)

Where
n represents an integer of 1 to 3,
R ¹ represents an alkyl group, a cycloalkyl group, a polycycloalkyl group or an aryl group,
R ² , R ³ , R ⁴ and R ⁵ may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a nitro group, A cyano group, or a dialkylamino group substituted with the same or different alkyl group, or adjacent groups of R ² , R ³ , R ⁴ and R ⁵ are each a carbon atom to which they are bonded; A ring may be formed together, and when R ^{1 to} R ⁵ represent a group containing a carbon atom, one or more hydrogen atoms on the carbon atom are a halogen atom, an alkyl group, a cyclo An alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group or an aryloxy group may be substituted,
Indicated by

Here, R ¹ represents an alkyl group, a cycloalkyl group, a polycycloalkyl group or an aryl group, and the alkyl group, the cycloalkyl group and the aryl group are defined as substituents on the carbon atom of X. It is synonymous.

  As the polycycloalkyl group, a polycycloalkyl group having 6 to 10 carbon atoms is preferable, and bicyclo- [2.1.1] -hexyl group, bicyclo- [2.2.1] -heptyl group, bicyclo- [2.2.2] -octyl group, bicyclo- [3.3.0] -octyl group, bicyclo- [4.3.0] -nonyl group, bicyclo- [4.4.0] -octyl group, And an adamantyl group.

R ² , R ³ , R ⁴ and R ⁵ are substituted with halogen atoms, alkyl groups, alkenyl groups, aryl groups, aralkyl groups, alkoxy groups, aryloxy groups, nitro groups, cyano groups, or the same or different alkyl groups. These dialkylamino groups are the same as those defined as the substituent on the carbon atom of X.

The adjacent groups of R ² , R ³ , R ⁴ and R ⁵ may be combined with the carbon atom to which they are bonded to form a ring. In the general formula (2), when R ² and R ³ (or R ⁴ and R ⁵ ) form a ring together with the carbon atom to which they are bonded, examples of the ring include a cyclopentene ring, Examples thereof include carbocyclic rings having 5 to 14 carbon atoms such as cyclohexene ring, cycloheptene ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, benzene ring, naphthalene ring and the like.

Incidentally, R ¹ to R ⁵ is, if a group containing a carbon atom, one or more hydrogen atoms on that carbon atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an aralkyl group , An alkoxy group or an aryloxy group may be substituted, and these groups are also synonymous with those defined as the substituent on the carbon atom of X.

Among these, R ¹ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 7 carbon atoms, a polycycloalkyl group having 6 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms. R ² , R ³ , R ⁴ and R ⁵ are independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkenyl group having 2 to 20 carbon atoms. An aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, a nitro group, a cyano group, or the same or A dialkylamino group substituted with two different alkyl groups having 1 to 6 carbon atoms is preferable.
In particular, R ¹ is preferably a tert-butyl group, a 2,6-diisopropylphenyl group, a 2,4,6-trimethylphenyl group, or an adamantyl group. In particular, R ² , R ³ , R ⁴ and R ⁵ are preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and adjacent to R ² , R ³ , R ⁴ and R ⁵ . When the groups being bonded together form a ring together with the carbon atoms to which they are bonded, those that form a cyclohexane ring are preferred, such as a cyclohexane ring, 1-methyl-4-propyl A hexane ring is preferred.

  Specific examples of the nitrogen-containing heterocyclic carbene ligand (L) in the present invention include compounds represented by formulas (3) to (18).

  The substituted ethynyl gold-cyclic alkylaminocarbene complex represented by the general formula (1) of the present invention is, for example, a reaction process formula [1]

Where
X and L are as defined above, and P represents a monodentate phosphine ligand.
It can be obtained by reacting a substituted ethynyl gold phosphine complex with a cyclic alkylaminocarbene ligand (L).

  Examples of the monodentate phosphine ligand include bis (pentafluorophenyl) phenylphosphine, (4-bromophenyl) diphenylphosphine, diallylphenylphosphine, dicyclohexylphenylphosphine, diethylphenylphosphine, and 4- (dimethylamino) phenyldiphenylphosphine. , Dimethylphenylphosphine, diphenyl (2-methoxyphenyl) phosphine, diphenyl (pentafluorophenyl) phosphine, diphenylpropylphosphine, diphenyl-2-pyridylphosphine, diphenyl (p-tolyl) phosphine, diphenylvinylphosphine, ethyldiphenylphosphine, isopropyl Diphenylphosphine, methyldiphenylphosphine, tribenzylphosphine, tributylphosphine Tri-t-butylphosphine, tricyclohexylphosphine, tricyclopentylphosphine, triethylphosphine, tri-2-furylphosphine, triisobutylphosphine, triisopropylphosphine, tripropylphosphine, trimethylphosphine, trioctylphosphine, triphenylphosphine, tris ( 4-chlorophenyl) phosphine, tris (3-chlorophenyl) phosphine, tris (2,6-dimethoxyphenyl) phosphine, tris (4-fluorophenyl) phosphine, tris (3-fluorophenylphosphine), tris (4-methoxyphenyl) Phosphine, Tris (3-methoxyphenyl) phosphine, Tris (2-methoxyphenyl) phosphine, Tris (4-trifluoromethylphenyl) Sphin, tris (pentafluorophenyl) phosphine, tris (2,4,6-trimethoxyphenyl) phosphine, tris (2,4,6-trimethylphenyl) phosphine, tri-m-tolylphosphine, tri-o-tolylphosphine , Tri-p-tolylphosphine, benzyldiphenylphosphine, bis (2-methoxyphenyl) phenylphosphine, diphenylcyclohexylphosphine, 2- (di-t-butylphosphino) biphenyl, 2- (dicyclohexylphosphino) biphenyl, neomenthyl Diphenylphosphine, p-tolyldiphenylphosphine, triallylphosphine, tris (2,4,4-trimethylpentyl) phosphine, tri (1-naphthyl) phosphine, tris (hydroxymethyl) phosphine, tris ( Hydroxypropyl) phosphine and the like. These can use a commercially available thing as it is.

  Examples of the substituted ethynyl gold phosphine complex include a reaction process formula [2]

Where
X and P are as defined above, and Y represents a halogen atom.
As shown in the above, it can be obtained by reacting a gold halogenophosphine complex with a substituted ethyne in the presence of a base (see, for example, Journal of Chemical Society, Dalton Trans., 411 (1986)).

  The gold halogenophosphine complex can be synthesized by a known method (see, for example, Experimental Chemistry Course, 4th edition, Maruzensha, page 455, volume 18 (1991)).

  The substituted ethyne may be a commercially available product, or can be synthesized from a substituted aromatic bromide by a known method (for example, see Journal of Organic Chemistry, 1985, 50, 1763).

  The cyclic alkylaminocarbene ligand is obtained by reacting a corresponding cyclic iminium salt with a base such as lithium diisopropylamide by a known method (for example, International Publication No. 2006/138166). (See brochure).

  In the synthesis of the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention, the amount of the cyclic alkylaminocarbene ligand used is preferably 1 to 10 mol, more preferably 1 with respect to 1 mol of the substituted ethynylgold phosphine complex. ~ 4 moles.

  The solvent used in the synthesis of the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention is not particularly limited as long as it does not inhibit the reaction. For example, tetrahydrofuran, furan, dioxane, tetrahydropyran, diethyl ether, diisopropyl ether, Ethers such as dibutyl ether, aliphatic hydrocarbons such as pentane, hexane, heptane and octane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated aliphatic hydrocarbons such as dichloromethane, dichloroethane and dichloropropane Aromatic hydrocarbons such as chlorobenzene are used. These solvents may be used alone or in combination of two or more.

  Although the usage-amount of the said solvent is suitably adjusted with the uniformity and stirring property of a reaction liquid, Preferably it is 1-30L with respect to 1 mol of substituted ethynyl gold phosphine complexes, More preferably, it is 5-20L.

  The synthesis of the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention is carried out, for example, by a method of mixing a substituted ethynylgold phosphine complex, a cyclic alkylaminocarbene ligand and a solvent and reacting them with stirring. The reaction temperature at that time is preferably 0 to 120 ° C., more preferably 20 to 100 ° C., and the reaction pressure is not particularly limited.

  After completion of the reaction, the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention is isolated and produced by a known method such as neutralization, extraction, filtration, concentration, distillation, recrystallization, sublimation, and chromatography.

  Examples of the substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention include compounds represented by formulas (19) to (49).

The substituted ethynyl gold-cyclic alkylaminocarbene complex of the present invention has an emission peak maximum due to an electroluminescence element in a deep blue region of 440 nm or less (410 to 440 nm) in chloroform at a temperature of 77 K (Kelvin) and under ultraviolet irradiation. and light emission color y coordinate in the CIE (Commission Internationale de l'Eclairage) color system is able to realize a device that is less than 0.18, be suitably used was suggested in an organic electroluminescence element .

  Next, embodiments of the organic electroluminescence element of the present invention will be described.

  The organic electroluminescence device of the present invention comprises the substituted ethynyl gold-cyclic alkylaminocarbene complex in at least one of the organic compound thin layers, and preferably a single layer or multilayer organic layer between a pair of electrodes. An organic electroluminescence device having a compound layer.

  The amount of the substituted ethynyl gold-cyclic alkylaminocarbene complex added to the organic compound layer is not particularly limited, but is preferably 0.005 to 1 g, and more preferably 0.001 to 1 g of the organic compound layer. 01 to 0.50 g, particularly preferably 0.01 to 0.15 g.

  This organic electroluminescent element can also be used in combination with a light emitting material, other doping materials, a hole injection material and an electron injection material. Furthermore, each of the hole injection layer, the light emitting layer, and the electron injection layer may be formed with a layer configuration of two or more layers. In that case, in the case of a hole injection layer, the layer that injects holes from the electrode is a hole injection layer, and the layer that receives holes from the hole injection layer and transports holes to the light emitting layer is a hole transport layer. Call. Similarly, in the case of an electron injection layer, a layer that injects electrons from an electrode is referred to as an electron injection layer, and a layer that receives electrons from the electron injection layer and transports electrons to a light emitting layer is referred to as an electron transport layer. Each of these layers is selected and used depending on factors such as the energy level of the material, heat resistance, adhesion with the organic compound layer or the metal electrode.

  Examples of the light emitting material or host material that can be used in the organic compound layer together with the substituted ethynyl gold-cyclic alkylaminocarbene complex include various carbazole derivatives, condensed polycyclic aromatics (anthracene, naphthalene, phenanthrene, pyrene, tetracene, pentacene, coronene, chrysene). Fluorescein, perylene, rubrene and derivatives thereof), phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, coumarin, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, Quinoline metal complex, diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine, merocyanine, imi Tetrazole chelated oxinoid compounds, quinacridone, rubrene, stilbene derivatives, aromatic silicon compound, and aromatic germanium compounds.

Among known hole injection materials that can be used in the organic electroluminescence device of the present invention, effective hole injection materials are aromatic tertiary amine derivatives, phthalocyanine derivatives, or triphenylene derivatives. Specific embodiments of the aromatic tertiary amine derivative include triphenylamine, tolylamine, tolyldiphenylamine, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4 , 4′-diamine (hereinafter referred to as TPD), N, N, N ′, N ′-(4-methylphenyl) -1,1′-phenyl-4,4′-diamine, N, N, N ′ , N ′-(4-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N′-diphenyl-N, N′-dinaphthyl-1,1′-biphenyl-4,4 ′ -Diamine, N, N '-(methylphenyl) -N, N'-(4-n-butylphenyl) -phenanthrene-9,10-diamine, 1,1-bis [4- (di-4-tolylamino) Phenyl] cyclohexane, etc., or these aromatic tertiary amine skeletons And oligomers or polymers, but is not limited thereto.
Specific embodiments of the phthalocyanine (Pc) derivative include H ₂ Pc, CuPc, CoPc, NiPc, ZnPc, PdPc, FePc, MnPc, ClAlPc, ClGaPc, ClInPc, ClSnPc, Cl ₂ SiPc, (HO) AlPc, (HO) Although it is a phthalocyanine derivative and a naphthalocyanine derivative such as GaPc, VOPc, TiOPc, MoOPc, and GaPc-O-GaPc, it is not limited thereto.
A specific embodiment of the triphenylene derivative is represented by the following formula.

Where
Z represents a single or plural alkyl group, cycloalkyl group, aryl group, aralkyl group or heterocyclic group, and one or more hydrogen atoms on the carbon atom of Z are a halogen atom, alkyl group, cycloalkyl A group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a dialkylamino group substituted with the same or different alkyl group, an alkylcarbonyl group, an arylcarbonyl group, or an organosilyl group. Substituents other than the organosilyl group are synonymous with those defined as being optionally substituted on the carbon atom of X.

  Examples of the organosilyl group include a trimethylsilyl group, a triethylsilyl group, a tert-butyldimethylsilyl group, a triisopropylsilyl group, and a tert-butyldiphenylsilyl group.

In the organic electroluminescence device of the present invention, a more effective known electron injection material is a metal complex compound or a nitrogen-containing five-membered ring derivative. Specific embodiments of the metal complex compound include 8-hydroxyquinolinate lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato) aluminum (hereinafter, Alq ₃ and described.), tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, bis (10 Hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] quinolinato) zinc, bis (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (o-cresolate) Gallium, bis (2-methyl-8-quinolinato) (1-naphtholato) al Examples thereof include, but are not limited to, minium and bis (2-methyl-8-quinolinato) (2-naphtholate) gallium.

  The nitrogen-containing five-membered ring derivative is preferably an oxazole, thiazole, oxadiazole, thiadiazole or triazole derivative. Specifically, 2,5-bis (1-phenyl) -1,3,4-oxazole and dimethyl POPOP (where POPOP represents 1,4-bis (5-phenyloxazol-2-yl) benzene). ), 2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5-bis (1-phenyl) -1,3,4-oxadiazole, 2- (4′-tert- Butylphenyl) -5- (4 "-biphenyl) -1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1,3,4-oxadiazole, 1,4-bis [ 2- (5-phenyloxadiazolyl)] benzene, 1,4-bis [2- (5-phenyloxadiazolyl) -4-tert-butylbenzene], 2- (4′-tert-butylphenyl)- 5- (4 ″ -biphenyl) -1,3,4 Thiadiazole, 2,5-bis (1-naphthyl) -1,3,4-thiadiazole, 1,4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4′-tert-butylphenyl) ) -5- (4 ″ -biphenyl) -1,3,4-triazole, 3- (4-biphenylyl) -4-phenyl-5-tert-butylphenyl-1,2,4-triazole, 2,5 -Bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like may be mentioned, but are not limited thereto.

  In the organic electroluminescence device of the present invention, an inorganic compound layer may be provided between the light emitting layer and the electrode in order to improve the charge injection property.

Examples of the inorganic compound layer include fluorides and oxides of alkali metals or alkaline earth metals such as LiF, Li ₂ O, RaO, SrO, BaF ₂ , and SrF ₂ .

  As the conductive material used for the anode of the organic electroluminescence device of the present invention, a material having a work function larger than 4 eV is suitable, and carbon atoms, aluminum, vanadium, iron, cobalt, nickel, tungsten, silver, gold , Platinum, palladium and their alloys, ITO (substance with 5-10% tin oxide added to indium oxide) substrate, tin oxide used for NESA substrate, metal oxide such as indium oxide, and organic such as polythiophene and polypyrrole A conductive resin can be used.

  As the conductive material used for the cathode, a material having a work function smaller than 4 eV is suitable, and magnesium, calcium, tin, lead, titanium, yttrium, lithium, ruthenium, manganese, aluminum, and alloys thereof are used. It is done. Here, examples of the alloy include magnesium / silver, magnesium / indium, lithium / aluminum, and the like. The ratio of the alloy is not particularly limited and is controlled by the temperature of the vapor deposition source, the atmosphere, the degree of vacuum, and the like.

  If necessary, the anode and the cathode may be formed of two or more layers.

  As for the organic electroluminescent element of this invention, it is desirable for at least one surface to be transparent in the light emission wavelength range of an element. The substrate is also preferably transparent.

  The transparent electrode is obtained by using the above-described conductive material and setting so as to ensure a predetermined translucency by a method such as vapor deposition or sputtering.

  The electrode on the light emitting surface preferably has a light transmittance of 10% or more.

  The substrate is not particularly limited as long as it has mechanical and thermal strength and has transparency, and examples thereof include a glass substrate and a transparent resin film.

  Transparent resin films include polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polypropylene, polystyrene, polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether ketone. , Polysulfone, polyethersulfone, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polyvinyl fluoride, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polychlorotrifluoroethylene, Polyvinylidene fluoride, polyester, polycarbonate, polyurethane, polyimide, polyetherimide, polyimide, polypropylene, etc. It is.

  The organic electroluminescence device of the present invention can be provided with a protective layer on the surface of the device or can be protected by silicon oil, resin, etc., in order to improve stability against temperature, humidity, atmosphere, etc. .

  In addition, the formation of each layer of the organic electroluminescence element should be performed by any one of dry film formation methods such as vacuum deposition, sputtering, plasma, and ion plating, or wet film formation methods such as spin coating, dipping, and flow coating. Can do. The film thickness is not particularly limited, but the normal film thickness is in the range of 5 nm to 10 μm, and more preferably in the range of 10 nm to 0.2 μm.

  In the case of a wet film-forming method, a thin film can be prepared by dissolving or dispersing the compound represented by the general formula (1) on each layer in a solvent such as ethanol, chloroform, tetrahydrofuran, or dioxane.

As a dry film-forming method, vacuum deposition is preferable, and a vacuum deposition apparatus is used, the degree of vacuum is 2 × 10 ⁻³ Pa or less, the substrate temperature is set to room temperature, and the dry deposition method is represented by the formula (1) of the present invention placed in a deposition cell. A thin film can be prepared by heating a substituted ethynyl gold-cyclic alkylaminocarbene complex and evaporating the material. At this time, in order to control the temperature of the vapor deposition source, a thermocouple or a non-contact infrared thermometer brought into contact with the vapor deposition cell is preferably used. A vapor deposition film thickness meter is preferably used to control the vapor deposition amount.

  As a vapor deposition film thickness meter, a quartz crystal unit installed opposite to a vapor deposition source is used, and the weight of the vapor deposition film adhering to the surface of the quartz crystal unit is measured from a change in the oscillation frequency of the crystal unit. From the above, the type in which the film thickness is obtained in real time is preferably used.

  Co-evaporation of the substituted ethynyl gold-cyclic alkylaminocarbene complex represented by the general formula (1) and the light emitting material or other host material is performed by using an evaporation source for each and controlling the temperature independently. Can do.

  Here, any organic thin film layer is made of polystyrene, polycarbonate, polyacrylate, polyester, polyamide, polyurethane, polysulfone, polymethyl methacrylate, polymethyl acrylate, cellulose, etc. Insulating resins and copolymers thereof, photoconductive resins such as poly-N-vinylcarbazole and polysilane, resins such as conductive resins such as polythiophene and polypyrrole, antioxidants, ultraviolet absorbers, plasticizers, etc. Additives can be used.

  The organic electroluminescence device of the present invention is used in, for example, a flat light emitter such as a wall-mounted TV or a flat panel display of a mobile phone, a copying machine, a printer, a backlight of a liquid crystal display, or a light source such as an instrument, a display board, a marker lamp, etc. Available.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the scope of the present invention is not limited to these examples.

Example 1 (Synthesis of [N- (2 ′, 6′-diisopropylphenyl) -2,2,4,4-tetramethylpyrrolidinylidene-4 ″ -fluorophenylethynylgold (23)])
1- (2,6-diisopropylphenyl) -2,2,4,4-tetramethyl-3,4-dihydro-2H-pyrrolium-trifluoromethanesulfonate (261 mg, 0.6 mmol) in a 30 ml Schlenk tube under argon atmosphere , Tetrahydrofuran (6 ml) was added to give a suspension. Lithium diisopropylamide (2.0 M solution, 300 μl, 0.6 mmol) was added at −78 ° C., and the mixture was stirred for 5 minutes and then at room temperature for 45 minutes, and then diisopropylamine as a by-product of tetrahydrofuran was distilled off under reduced pressure. Tetrahydrofuran (8 ml) was added, and the mixture was stirred at 70 ° C. for 5 minutes. The reaction mixture was filtered, and the filtrate was added with 4-fluorophenylethynyl (triphenylphosphine) gold (116 mg, 0.2 mmol), then at room temperature. For 2 hours. Tetrahydrofuran was distilled off under reduced pressure, methylene chloride was added, and the mixture was washed with water to adjust the pH to 7. After drying with sodium sulfate, the solvent was distilled off under reduced pressure using an evaporator. The reaction crude product was purified by column chromatography using silica gel (Hexane / AcOEt = 6/1) to obtain 62.4 mg of the target product as a white solid (yield 51%).

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.24-7.42 (m, 5H), 6.81-6.85 (m, 2H), 2.75-2.81 (sept, 2H) 2.07 (s, 2H), 1.53 (s, 6H), 1.44 (d, 6H), 1.34 (s, 6H), 1.31 (d, 6H)
EI-MS (M / Z): 601 (M +), CI (m / z): 602 (MH +)
Luminescence analysis (CHCl ₃ , 77K, Ex 250 nm) λ (nm): 412 (max)
Thermal analysis: Melting point: 212 ° C
Elemental analysis Observation C: 56.0, H: 5.9, N: 2.3
Theoretical value C: 55.9, H: 5.9, N: 2.3

Example 2 (Preparation of organic electroluminescence device)
The electroluminescence element shown in FIG. 2 was produced as follows.
Using glass with an indium tin oxide (hereinafter abbreviated as ITO) film manufactured by ECH as a transparent electrode substrate, using a vacuum evaporation device manufactured by ULVAC Kiko, a vacuum degree of 2 × 10 ⁻³ Pa or less is formed on the substrate. The hole transport layer 3 made of 2- (4′-trimethylsilylphenyl) triphenylene is 40 nm thick, and the host is 2-methyl-1,4-bis (triphenylgermyl) benzene (hereinafter abbreviated as Me-p-BTPGB). ) As a guest phosphorescent complex (N- (2 ′, 6′-diisopropylphenyl) -2,2,4,4-tetramethylpyrrolidinylidene-4 ″ -fluorophenylethynylgold (hereinafter referred to as phosphorescent complex) (Abbreviated as (23)) of the light-emitting layer 4 containing 5.0% by weight of 30 nm thick, 3- (4-biphenylyl) -4-phenyl-5-tert-butylphenyl-1,2,4 The hole blocking layer 5 made of triazole (sublimation purified product; hereinafter abbreviated as TAZ) is 30 nm, the electron transport layer 6 made of lithium fluoride (hereinafter abbreviated as LiF) is 0.5 nm, and the electrode 7 is aluminum (hereinafter referred to as Al). For 100 nm and sequentially vacuum-deposited to produce an electroluminescent device.
The vacuum deposition was performed by charging the raw material in a crucible placed opposite to the substrate and heating the raw material together with the crucible.

Comparative example (production of organic electroluminescence device)
As a comparative example, an organic electroluminescence element was produced in the same manner as in Example 2 except that the phosphorescent complex (23) was not included in the light emitting layer 4.

When the ITO electrode 2 of the electroluminescent element of Example 2 was energized with the Al electrode 7 as the negative electrode and energized to increase the voltage between the electrodes, the element started to emit blue light that was clearly visible to the naked eye from around +12 V, and +24 V Light was emitted at 4.6 cd / m ² . The efficiency of the current related to light emission of this element was determined by the following equation.

Current efficiency = (luminescence brightness per unit area) / (current density per unit area)

The current efficiency thus determined was 0.014 cd / A at + 21V.
The emission color of this element was measured using a spectrophotometer manufactured by JASCO. From the spectrum obtained at an interelectrode voltage of +19 V, the values of chromaticity coordinates determined by JIS Z8701 were x = 0.169 and y = 0.139.

  The emission spectrum (in chloroform, temperature 77K (Kelvin), under ultraviolet irradiation) of the phosphorescent complex (23) synthesized in Example 1 and the organic electroluminescent elements of Example 2 and Comparative Example was measured with a phosphorescence fluorometer. .

  As shown in FIG. 1, the organic electroluminescence element of Example 2 exhibited a light emission peak maximum in a deep blue region (410 to 440 nm) of 440 nm or less. On the other hand, the organic electroluminescent element of the comparative example which does not contain the phosphorescent complex (23) in the light emitting layer exhibited a light emission peak maximum near 380 nm outside the deep blue region (ultraviolet region). Note that the electroluminescent element of the comparative example was energized with the ITO electrode 2 as the positive electrode and the Al electrode 7 as the negative electrode to increase the voltage between the electrodes, but only weak light emission was observed in the ultraviolet region of 380 nm. It was.

  According to the present invention, in a phosphorescent organic electroluminescence device, the deep blue region (410 nm to 440 nm) of 440 nm or less, which is important for completing a full color display, has an emission peak maximum due to electroluminescence, and the emission color is CIE. (International Lighting Commission) It is possible to realize an element in which the y coordinate is less than 0.180 in the color system.

Claims (8)

General formula (1)

Where
L represents the general formula (2)

In the formula, n represents 1, R ¹ represents an alkyl group, a cycloalkyl group, a polycycloalkyl group or an aryl group, and R ² , R ³ , R ⁴ and R ⁵ may be the same or different from each other. Represents a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a nitro group, a cyano group, or a dialkylamino group substituted with two identical or different alkyl groups Or R ⁴ and R ⁵ may be combined with the carbon atom to which they are bonded to form a ring, and when R ^{1 to} R ⁵ represent a group containing a carbon atom, the carbon atom One or more of the hydrogen atoms above is substituted with a halogen atom, alkyl group, cycloalkyl group, alkenyl group, aryl group, aralkyl group, alkoxy group or aryloxy group It may have,
A cyclic alkylaminocarbene ligand represented by:
X represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or a heterocyclic group, wherein one or more hydrogen atoms on the carbon atom of X are independently a halogen atom, an alkyl group, Cycloalkyl group, alkenyl group, aryl group, aralkyl group, alkoxy group, aryloxy group, dialkylamino group substituted with the same or different alkyl group, alkylcarbonyl group, arylcarbonyl group, alkyl mercapto group, aryl mercapto group, alkyl A sulfonyl group or an arylsulfonyl group may be substituted, and a plurality of hydrogen atoms on the carbon atom of X are independently an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group, or the same Or a dialkylamino group substituted with a different alkyl group, Le carbonyl group, an arylcarbonyl group, alkylmercapto group, arylmercapto group, if alkylsulfonyl group or substituted with an arylsulfonyl group, bonded groups each other adjacent may form a ring,
A substituted ethynyl gold-cyclic alkylaminocarbene complex represented by the formula: R ¹ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 7 carbon atoms, a polycycloalkyl group having 6 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms,
R ² , R ³ , R ⁴ and R ⁵ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or 6 to 20 carbon atoms. Substituted with an aryl group, an aralkyl group having 7 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, a nitro group, a cyano group, or two identical or different alkyl groups and a dialkylamino group, a substituted ethynyl gold claim 1, wherein - cyclic alkylamino carbene complexes. R ¹ is a polycycloalkyl group, and the polycycloalkyl group is a bicyclo- [2.1.1] -hexyl group, a bicyclo- [2.2.1] -heptyl group, or a bicyclo- [2.2. .2] -octyl group, bicyclo- [3.3.0] -octyl group, bicyclo- [4.3.0] -nonyl group, bicyclo- [4.4.0] -octyl group and adamantyl group 3. A substituted ethynyl gold-cyclic alkylaminocarbene complex according to claim 2 selected from the group.   The process for producing a substituted ethynylgold-cyclic alkylaminocarbene complex according to claim 1, wherein the substituted ethynylgoldphosphine complex is reacted with a cyclic alkylaminocarbene ligand. The process according to claim 4 , wherein the cyclic alkylaminocarbene ligand is obtained by reacting a cyclic iminium salt with a base. The process according to claim 4 or 5 , wherein the reaction uses 1 to 5 mol of a cyclic alkylaminocarbene ligand with respect to 1 mol of the substituted ethynylgold phosphine complex . Reaction, a mixture of substituted ethynyl gold phosphine complex with a cyclic alkyl amino carbene ligand, the presence of a solvent, is carried out by stirring at a temperature of 0 to 120 ° C., to any one of claims 4-6 The manufacturing method described.   An organic electroluminescence device in which a light emitting layer or a plurality of organic compound thin layers including a light emitting layer is formed between a pair of electrodes, wherein the organic compound thin layer is one type or two or more types. The organic electroluminescent element characterized by including the substituted ethynyl gold- cyclic alkylamino carbene complex shown by these.

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