JP4556871B2 - Heterocyclic substituted phenylacetylene compound, method for producing the same, and organic electroluminescence device using the same - Google Patents

Description

  The present invention is useful for a blue light emitting material for an electroluminescent element (organic electroluminescent element), etc. (1):

In the formula, n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group, When n ¹ is 2 or 3, A represents a divalent or trivalent aryl group or heterocyclic group, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, and X represents O or S N ² represents an integer of 1 to 4;
The heterocyclic substituted phenylacetylene compound shown by these, its manufacturing method, and the organic electroluminescent element containing this compound.

  The heterocyclic-substituted phenylacetylene compound represented by the formula (1) is a novel compound. Therefore, nothing is known about its use as a material for organic electroluminescence elements.

  The present invention provides a heterocyclic-substituted phenylacetylene compound that exhibits intense blue light emission under ultraviolet irradiation and an organic electroluminescence device containing the same.

  As a result of intensive studies, the present inventors have found that the organic electroluminescence device containing the novel heterocyclic-substituted phenylacetylene compound represented by the formula (1) exhibits blue-white light emission when a voltage is applied. The novel heterocycle-substituted phenylacetylene compound represented by (1) exhibits strong blue light emission upon irradiation with ultraviolet light in a chloroform solution, and has been found to be extremely useful as an organic electroluminescence device material, leading to the present invention.

That is, the present invention is as follows.
The first invention is the following formula (1):

In the formula, n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group, When n ¹ is 2 or 3, A represents a divalent or trivalent aryl group or heterocyclic group, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, and X represents O or S N ² represents an integer of 1 to 4;
It is related with the heterocyclic substituted phenylacetylene compound shown by these.

  The second invention uses a zerovalent palladium compound as a catalyst, and has the following formula (5):

In the formula, R ¹ , X and n ² are as defined above.
A heterocyclic-substituted phenyl trifluoromethanesulfonate compound represented by the following formula (6):

In the formula, n ¹ and A are as defined above.
The terminal acetylene compound shown by these is made to react in a basic solvent, It is related with the manufacturing method of the heterocyclic substituted phenyl acetylene compound shown by said Formula (1) characterized by the above-mentioned.

  3rd invention is an organic electroluminescent element which has an organic compound thin layer between a pair of electrodes, Comprising: This organic compound thin layer contains the heterocyclic substituted phenyl acetylene compound shown by said Formula (1). The organic electroluminescent element characterized by these.

In the heterocyclic-substituted phenylacetylene compound of the first invention (formula (1)), n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A is a hydrogen atom, an alkyl group, a cycloalkyl group, Represents an aryl group, an aralkyl group, an alkylsilyl group, or a heterocycle, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, and when n ¹ is 2 or 3, A is divalent or Represents a trivalent aryl group or a heterocyclic group, X represents O or S, and n ² represents an integer of 1 to 4;

  When A is an alkyl group, examples of the alkyl group include those having 1 to 10 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl. An alkyl group is mentioned. These substituents include isomers thereof.

  In the case of a cycloalkyl group, examples of the cycloalkyl group include cycloalkyl groups having 3 to 7 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.

  In the case of an aryl group, examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a dimethylnaphthyl group. These substituents include isomers thereof.

  In the case of an aralkyl group, examples of the aralkyl group include benzyl group, phenethyl group, phenylpropyl group, phenylbutyl group, naphthylmethyl group, naphthylethyl group, naphthylpropyl group, naphthylmethyl group, diphenylmethyl group and the like.

In the case of an alkylsilyl group, examples of the alkylsilyl group include a trimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a tributylsilyl group, a methyldiisopropylsilyl group, a tert-butyldimethylsilyl group, and a methyldi-tert-butylsilyl group. .
In the case of a heterocyclic compound group, a quinolyl group, a quinazolinyl group, a quinoxalinyl group, an imidazolyl group, and the like can be given.
When n ¹ is 2, A is a divalent aryl group or a divalent heterocyclic group, and when n ¹ is 3, A is a trivalent aryl group or a trivalent heterocyclic group. is there. Examples of these groups include bivalent or trivalent aryl groups or heterocyclic groups described above.

  In the above-mentioned substituents exemplified as A, the hydrogen atom bonded to the carbon atom is further a heterocyclic group (benzoxazolyl group, benzothiazolyl group), halogen atom (fluorine atom, chlorine atom, bromine atom, or iodine) Atoms), dialkylamino groups (dimethylamino group, diethylamino group, dipropylamino group (and isomers thereof) and other C2-C10 dialkylamino groups (note that these substituents include isomers thereof). ), An aryloxy group (phenoxy group, triloxy group, xylyloxy group, naphthoxy group, aryloxy group having 6 to 14 carbon atoms such as dimethylnaphthoxy group), alkoxy group (methoxy group, ethoxy group, propoxy group, butoxy group, Such as pentanoxy group, hexanoxy group, heptanoxy group, octanoxy group, nonanoxy group, decanoxy group, etc. 1 to 10 alkoxy groups), alkenyl groups (vinyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, etc.) 20, particularly 2 to 12 alkenyl groups), a nitro group, a cyano group, or an alkyl group, a cycloalkyl group, or an aryl group as defined above. These substituents include isomers thereof.

In the heterocycle-substituted phenylacetylene compound of the first invention (the above formula (1)), when R ¹ is an alkyl group, the alkyl group includes a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. , An alkyl group having 1 to 10 carbon atoms such as a heptyl group, an octyl group, a nonyl group, and a decyl group. These substituents include isomers thereof.

When R ¹ is a haloalkyl group, the haloalkyl group includes a haloalkyl group having 1 to 5 carbon atoms such as a trifluoromethyl group, a difluoromethyl group, a trifluoroethyl group, a difluoroethyl group, a dichloromethyl group, and a dibromomethyl group. Can be mentioned.

When R ¹ is an alkoxy group, examples of the alkoxy group include carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a nonyloxy group, and a decyloxy group. The alkoxy group of number 1-10 is mentioned. These substituents include isomers thereof.

When R ¹ is a haloalkoxy group, examples of the haloalkoxy group include a halomethoxy group such as a trifluoromethoxy group, a difluoromethoxy group, a trifluoroethoxy group, a difluoroethoxy group, a dichloromethoxy group, and a dibromomethoxy group. An alkoxy group is mentioned.

  Specific examples of the heterocyclic-substituted phenylacetylene compound (formula (1)) include 5-methyl-2- (2′-phenylethynylphenyl) benzoxazole, 5-methoxy-2- (2′- Phenylethynylphenyl) benzoxazole, 2- (2′-phenylethynylphenyl) benzoxazole, 5-trifluoromethoxy-2- (2′-phenylethynylphenyl) benzoxazole, 5-trifluoromethyl-2- (2 ′) -Phenylethynylphenyl) benzoxazole, 1,4-bis (2 '-(2 "-benzoxazolyl) phenylethynyl) benzene, 1,3-bis (2'-(2" -benzoxazolyl) phenyl Ethynyl) benzene, bis (2 ′-(2 ″ -benzoxazolyl) phenyl) acetylene, 2- 2'-ethynylphenyl) benzoxazole, 2- (2'-trimethylsilylethynyl) benzoxazole, 2- (2 '-(3 "-fluorophenylethynyl) phenyl) benzoxazole, 2- (2'-(4"- 2- (2′-alkynyl group-substituted phenyl) benzoxazole compounds such as phenylphenylethynyl) phenyl) benzoxazole, 2- (2 ′-(2 ″ -methyl-2 ″ -H-imidazolylethynyl) phenyl) benzoxazole, 5-methyl-2- (2′-phenylethynylphenyl) benzothiazole, 5-methoxy-2- (2′-phenylethynylphenyl) benzothiazole, 2- (2′-phenylethynylphenyl) benzothiazole, 5-tri Fluoromethoxy-2- (2′-phenylethynyl phen ) Benzothiazole, 5-trifluoromethyl-2- (2'-phenylethynylphenyl) benzothiazole, 2- (2'-phenylethynylphenyl) benzothiazole, 1,4-bis (2 '-(2 "- Benzothiazolyl) phenylethynyl) benzene, 1,3-bis (2 ′-(2 ″ -benzothiazolyl) phenylethynyl) benzene, bis (2- (2′-benzothiazolyl) phenyl) acetylene, 2- (2′-ethynylphenyl) Benzothiazole, 2- (2′-trimethylsilylethynyl) benzothiazole, 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzothiazole, 2- (2 ′-(4 ″ -phenylphenylethynyl) phenyl) Benzothiazole, 2- (2 ′-(2 ″ -methyl-2 ″ -H-imidazolyl) 2- (2'-alkynyl group-substituted phenyl) benzothiazole compounds such as ethynyl) phenyl) benzothiazole, and the like.

Among the heterocyclic substituted phenylacetylene compounds represented by the formula (1) in the present invention, in the present invention, heterocyclic substituted phenylacetylene compounds represented by the following formulas (2) to (4) are particularly preferable.

In the formula, R ² represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group.

Wherein, n ³ is an integer of 2-3.

In the heterocyclic substituted phenylacetylene compound represented by the formula (2), R ² represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group. In addition, the specific aspect of these substituents is the same as that of what was mentioned as A in the said Formula (1).

  Specific examples of the heterocyclic-substituted phenylacetylene compound (formula (2)) include 2- (2′-phenylethynylphenyl) benzoxazole and 2- (2 ′-(1 ″ -propynyl) phenyl). Benzoxazole, 2- (2 ′-(2 ″ -cyclopropylethynyl) phenyl) benzoxazole, 2- (2′-p-tolylethynylphenyl) benzoxazole, 2- (2′-trimethylsilylethynylphenyl) benzoxazole, 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzoxazole, 2- (2 ′-(4 ″ -phenylphenylethynyl) phenyl) benzoxazole, 2- (2 ′-(2 ″ -methyl-) 2 "-H-imidazolylethynyl) phenyl) benzoxazole and the like.

In the heterocyclic-substituted phenylacetylene compound represented by the formula (3), n ³ represents an integer of 2 to ³ .

  Specific examples include 1,4-bis (2 ′-(2 ″ -benzoxazolyl) phenylethynyl) benzene and 1,3-bis (2 ′-(2 ″ -benzoxazolyl) phenylethynyl. ) Benzene and the like.

  The heterocyclic-substituted phenylacetylene compound represented by the formula (4) is bis (2-benzoxazolyl) phenyl) acetylene.

  These heterocycle-substituted phenylacetylene compounds use a zerovalent palladium compound as a catalyst, and have the following formula (5):

In the formula, R ¹ , X and n ² are as defined above.

And a heterocycle-substituted phenyl trifluoromethanesulfonate compound represented by the following formula (6):

In the formula, n ¹ and A are as defined above.
It can manufacture by making the terminal acetylene compound shown by react in a basic solvent.

  Here, the heterocyclic-substituted phenyl trifluoromethanesulfonate compound (formula (5)) is described in, for example, Journal of the American Chemical Society (1987, 109, p. 5478). In the presence of an organic base such as triethylamine, trifluoromethanesulfonic anhydride and a hydroxy group-substituted condensed heterocyclic compound are reacted in a solvent such as methylene chloride.

  Examples of zero-valent palladium compounds used as catalysts include zero-valent palladium phosphine complexes (palladium tetrakistriphenylphosphine complex, bisdiphenylphosphinoethane palladium complex, bistricyclohexylphosphine palladium complex, etc.), zero-valent palladium olefin complexes (Trisdi). Benzylideneacetone dipalladium complex) and the like. Of these compounds, zero-valent palladium phosphine complexes are preferable, and tetrakis (triphenylphosphine) palladium is more preferable.

  The amount of these zerovalent palladium compounds used is 0.1 to 10 mol%, preferably 0.5 to 5 mol%, based on the heterocyclic substituted phenyltrifluoromethanesulfonate compound (formula (5)). .

In the terminal acetylene compound represented by the formula (6), A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic ring, and n ¹ represents an integer of ¹ to 3. Represent.

  These substituents represented by A have the same meaning as A in the formula (1).

  Specific embodiments of the terminal acetylene compound (formula (6)) include phenylacetylene, 3-fluorophenylacetylene, 4-phenylphenylacetylene, 5-ethynyl-1-methyl-1-H-imidazole, 1, Ethynyl such as 4-diethynylbenzene, 1,3-diethynylbenzene, 1,3,5-triethynylbenzene, 2- (2′-ethynylphenyl) benzoxazole, 2- (2′-ethynylphenyl) benzothiazole Group-substituted aryl compounds, 8-ethynyl group-substituted heterocyclic compounds such as 8-ethynylquinoline, 8-ethynylquinazoline, and 8-ethynylquinoxaline, alkylsilylacetylene compounds such as trimethylsilylacetylene, and alkyl such as 1-propyne and 1-butyne Alkene compounds, cyclohexylacetylene, etc. A cycloalkyl group substituted acetylene compound, an aralkyl group substituted acetylenic compounds such as 1-phenyl-propan-1-yne and the like.

Examples of the basic solvent used in this reaction include piperidine or pyrrolidine.
The usage-amount of a basic solvent is 1-20L (liter) with respect to 1 mol of heterocyclic substituted phenyl trifluoromethanesulfonate compounds, Preferably it is 1.5-5L.

Moreover, reaction temperature is 80-100 degreeC, Preferably it is 80-90 degreeC.
The reaction time varies depending on the kind of the terminal acetylene compound, the amount of solvent used, the reaction temperature, and the like, but is 1 to 5 hours.

  This reaction is usually performed in an inert gas atmosphere such as argon or nitrogen, or in a gas stream of these gases. The reaction pressure used is usually atmospheric pressure.

  The heterocyclic-substituted phenylacetylene compound (formula (1)) produced according to the above production method is subjected to usual post-treatments such as extraction, concentration, filtration and the like after the reaction, and distillation, recrystallization as necessary. It can be appropriately purified by known means such as various chromatographies.

  The obtained heterocyclic substituted phenylacetylene compound (formula (1)) is suitably used for an organic electroluminescence device.

  Hereinafter, the embodiment is shown about the organic electroluminescent element which is 3rd invention.

  The organic electroluminescence device of the third invention is an organic electroluminescence device having an organic compound thin layer between a pair of electrodes, wherein the organic compound thin layer is a heterocyclic substituted phenylacetylene compound represented by the formula (1). Among them, it contains at least one kind. Here, the organic compound thin layer is preferably a light emitting layer, an electron injection layer (or a hole block layer), or a hole injection layer.

  Furthermore, this organic electroluminescence element is an element in which a single-layer or multilayer organic compound thin layer is formed between an anode and a cathode.

  A single layer type organic electroluminescent element has a light emitting layer between an anode and a cathode. The light emitting layer contains a light emitting material, and further contains a hole injecting material or an electron injecting material (or hole blocking material) for transporting holes injected from the anode or electrons injected from the cathode to the light emitting material. May be.

  Multi-layer type organic electroluminescence devices include, for example, “anode / hole injection layer / light emitting layer / cathode”, “anode / light emitting layer / electron injection layer (or hole block layer) / cathode”, “anode / hole injection”. And a layered structure such as “layer / light emitting layer / electron injection layer (or hole block layer) / cathode”.

  In addition to the heterocyclic-substituted phenylacetylene compound (formula (1)), the light-emitting layer includes a known light-emitting material, doping material, hole injection material (phthalocyanine derivative, naphthalocyanine derivative, porphyrin derivative, oxazole, oxadiazole) , Triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone, tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, polyarylalkane, stilbene, butadiene, benzidine type triphenylamine, styrylamine type triphenylamine, diamine Type triphenylamine, derivatives thereof, and polymer materials such as polyvinyl carbazole, polysilane, and conductive polymers) and electron injection materials (or hole block materials) Fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane, anthrone and their derivatives) May be.

  The heterocyclic-substituted phenylacetylene compound (formula (1)) has a concentration of 0.5 to 100% by weight in any of the light-emitting layer, the electron injection layer (or hole block layer), the hole transport layer, and the hole injection layer. Is added.

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

  The light emitting material or host material that can be used in the organic compound thin layer together with the heterocyclic-substituted phenylacetylene compound (formula (1)) includes 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, aminoquinoline metal complex, benzoquinoline metal complex, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopi Emissions, polymethine, merocyanine, imidazole chelated oxinoid compounds, quinacridone, rubrene, stilbene derivatives and fluorescent dyes.

Of the known hole injection materials that can be used in the organic electroluminescence device of the present invention, more effective hole injection materials are aromatic tertiary amine derivatives or phthalocyanine derivatives. Specific examples of the aromatic tertiary amine derivative are 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, N, N-bis (4-di-4-tolylaminophenyl)- 4-Phenyl-cyclohexane etc., or these aromatic tertiary amines An oligomer or polymer having a rated, but not limited thereto.
Specific examples of phthalocyanine (Pc) derivatives are H ₂ Pc, CuPc, CoPc, NiPc, ZnPc, PdPc, FePc, MnPc, ClAlPc, ClGaPc, ClInPc, ClSnPc, Cl ₂ SiPc, (HO) AlPc, (HO) GaPc, Although it is a phthalocyanine derivative and a naphthalocyanine derivative such as VOPc, TiOPc, MoOPc, and GaPc-O-GaPc, it is not limited thereto.

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 examples of the metal complex compound include 8-hydroxyquinolinate lithium, bis (8-hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, tris ( 8-hydroxyquinolinate) aluminum (hereinafter referred to as Alq ₃ ), tris (2-methyl-8-hydroxyquinolinate) 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) aluminum Bis (2-methyl-8-quinolinato) (2-naphtholato) Gallium like, but is not limited thereto.

  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, dimethylbis (5′-phenyloxazolyl) 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 -Thiadiazole, 1,4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4'-tert-butylphenyl) -5- (4 "-biphenyl) -1,3,4-triazole , 2,5-bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like, but are not limited thereto. is not.

  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 alkali metal or alkaline earth metal fluorides and oxides 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, 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 conductivity such as polythiophene and polypyrrole Can be used.

  As the conductive material used for the cathode, those having a work function smaller than 4 eV are suitable, and magnesium, calcium, tin, lead, titanium, yttrium, lithium, ruthenium, manganese, aluminum and the like 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 is prepared by dissolving or dispersing a material such as a heterocyclic substituted phenylacetylene compound (formula (1)) forming each layer in a solvent such as ethanol, chloroform, tetrahydrofuran, or dioxane. Can do.

As the dry film-forming method, vacuum deposition is preferable, and the heterocycle-substituted phenylacetylene of the present invention is placed in an alumina deposition cell using a vacuum deposition apparatus, with a degree of vacuum of 2 × 10 ⁻³ Pa or less and a substrate temperature of room temperature. A thin film can be prepared by heating a compound (the above formula (1)) with a tungsten filament and evaporating the material.

  Co-evaporation of TPD and a heterocyclic substituted phenylacetylene compound (formula (1)) can be performed by using an evaporation source for each and controlling the temperature independently.

  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-vinyl carbazole 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 can be used for a flat light emitter such as a flat panel display of a wall-mounted television, a light source such as a copying machine, a printer, a backlight of a liquid crystal display or instruments, a display board, a marker lamp, and the like.

  The ultraviolet absorption maximum and the fluorescence maximum wavelength of the heterocyclic-substituted phenylacetylene compound of the first invention (formula (1)) were measured by the following methods.

  The ultraviolet absorption maximum wavelength is measured at room temperature (20 ° C.) using an ultraviolet spectrophotometer by dissolving a heterocyclic-substituted phenylacetylene compound (formula (1)) in chloroform (concentration 0.01 mg / ml). Went.

  The fluorescence maximum wavelength was measured at room temperature (20 ° C.) using the above-mentioned chloroform solution and a fluorescence spectrophotometer.

  The heterocycle-substituted phenylacetylene compound of the first invention (formula (1)) showed blue fluorescence having a fluorescence maximum at 380 to 400 nm when irradiated with ultraviolet rays having a wavelength of about 240 nm in a chloroform solution. Moreover, the organic electroluminescent element containing this realized blue fluorescence.

Hereinafter, the present invention will be specifically described with reference to Examples and Reference Examples.
Example 1

Synthesis of 2- (2'-phenylethynylphenyl) benzoxazole (following formula (7))

To 20 ml Schlenk, 340 mg (1.0 mmol) of 2′-trifluoromethylsulfonylphenylbenzoxazole, 27 mg (2.5 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 3 ml of piperidine were added and stirred. To this yellow reaction solution, 0.132 mL (1.2 mmol) of phenylacetylene was added and stirred at 80 ° C. for 2.5 hours. After completion of the reaction, a saturated aqueous ammonium chloride solution was added to the reaction mixture, the organic matter was extracted with methylene chloride, and the resulting organic layer was dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. The obtained reaction crude product is purified by column chromatography using silica gel (development solvent is gradually changed from hexane / ethyl acetate = 100/0 to 5/1), and is a yellow powder. The target compound was obtained. (178 mg, yield 64.3%)
The physical properties are shown below.

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.36-7.40 (m, 5H), 7.48-7.52 (m, 2H), 7.61-7.64 (m, 3H) , 7.73 (m, 1H), 7.84 (m, 1H), 8.26 (d, 1H)
EI-MS (m / z): 294 (M ⁺ -1), CI-MS (m / z): 296 (MH ⁺ )
[Absorption maximum: chloroform solution] 309 nm
[Fluorescence maximum wavelength: chloroform solution] 378 nm
Example 2

Synthesis of 1,4-bis (2 '-(benzoxazolyl) phenylethynyl) benzene (following formula (8))

To 20 ml Schlenk, 340 mg (1.0 mmol) of 2′-trifluoromethylsulfonylphenylbenzoxazole, 29 mg (2.5 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 3 ml of piperidine were added and stirred. To this yellow reaction solution, 63 mg (0.5 mmol) of 1,4-diethynylbenzene was added and stirred at 80 ° C. for 2.5 hours. A large amount of yellow precipitate was confirmed as the reaction proceeded. After completion of the reaction, the reaction mixture was diluted with methylene chloride, washed with a saturated aqueous ammonium chloride solution, and dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. The resulting reaction crude product is purified by column chromatography using silica gel (development solvent is gradually changed from hexane / ethyl acetate = 100/0 to 2/1). A yellow-orange powder was obtained. Further, this crude product was dissolved in methylene chloride and then cooled to -78 ° C. to obtain the desired product as a pale yellow powder. (146 mg, yield 56.8%)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.38-7.44 (m, 4H), 7.48-7.55 (m, 4H), 7.61-7.65 (m, 6H) , 7.73-7.77 (m, 2H), 7.83-7.87 (m, 2H), 8.27-8.30 (m, 2H)
EI-MS (m / z): 511 (M ⁺ -1), CI-MS (m / z): 513 (MH ⁺ )
Elemental analysis theoretical value _{(C 36 H 20 N 2 O} 2) C: 84.36%, H: 3.93%, N: 5.47%
Actual value C: 83.00%, H: 4.08%, N: 5.56%
[Absorption maximum: chloroform solution] 291 nm
[Fluorescence maximum wavelength: chloroform solution] 400 nm
Example 3

Synthesis of 1,3-bis (2- (benzoxazolyl) phenylethynyl) benzene (following formula (9))

To 20 ml Schlenk, 345 mg (1.0 mmol) of 2′-trifluoromethylsulfonylphenylbenzoxazole, 29 mg (2.5 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 3 ml of piperidine were added and stirred. To this yellow reaction solution, 63 mg (0.5 mmol) of 1,3-diethynylbenzene was added and stirred at 80 ° C. for 2.5 hours. After completion of the reaction, the reaction mixture was diluted with methylene chloride, washed with a saturated aqueous ammonium chloride solution, and dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. The obtained orange reaction crude product was dissolved in methylene chloride, cooled to −78 ° C., and cooled diethyl ether was added in the same manner to obtain the target compound as a white powder. (109 mg, 42.6% yield)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.29-7.32 (m, 4H), 7.41 (t, 1H), 7.51-7.62 (m, 8H), 7.73 -7.76 (m, 2H), 7.79-7.83 (m, 2H), 7.96 (s, 1H), 8.28-8.31 (m, 2H)
EI-MS (m / z): 511 (M ⁺ -1), CI-MS (m / z): 513 (MH ⁺ )
Elemental analysis theoretical value _{(C 36 H 20 N 2 O} 2) C: 84.36%, H: 3.93%, N: 5.47%
Actual value C: 83.65%, H: 4.04%, N: 5.43%
[Absorption maximum: chloroform solution] 280 nm
[Fluorescence maximum wavelength: chloroform solution] 379 nm
Example 4

Synthesis of bis (2- (benzoxazolyl) phenyl) acetylene (following formula (4))

To a 200 ml reaction vessel, 2.01 g (5.8 mmol) of 2′-trifluoromethylsulfonylphenylbenzoxazole, 65 mg (6.0 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 17 ml of piperidine were added and stirred. To this yellow reaction solution, 0.85 ml (6.1 mmol) of trimethylsilylacetylene was added and stirred at 100 ° C. for 1.5 hours. After completion of the reaction, the reaction mixture was diluted with methylene chloride and washed with a saturated aqueous ammonium chloride solution. After filtration, the filtrate was dried under reduced pressure to obtain 2-trimethylsilylethynylphenylbenzoxazole.
Next, the obtained 2-trimethylsilylethynylphenylbenzoxazole was dissolved in 18 ml of methanol, 6 ml of a 1 mol / L aqueous sodium hydroxide solution was added dropwise, and the mixture was stirred at room temperature for 2 hours. After completion of the reaction, 30 ml of water was added to the reaction mixture, and then the organic matter was extracted with methylene chloride. The obtained organic layer was dried over anhydrous magnesium sulfate, filtered, and the filtrate was dried under reduced pressure to give 2-ethynylphenyl. Benzoxazole was obtained.
To the obtained 2-ethynylphenylbenzoxazole, 1.58 g (4.5 mmol) of 2′-trifluoromethylsulfonylphenylbenzoxazole, 51 mg (4.5 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium, and 13 ml of piperidine were added. Stir at 100 ° C. for 3 hours. After completion of the reaction, a saturated aqueous ammonium chloride solution was added to the reaction mixture, the organic matter was extracted with methylene chloride, and the resulting organic layer was dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. The obtained reddish brown oily substance was dissolved in methylene chloride and cooled to -78 ° C to obtain the target compound as a pale yellow powder. (730 mg, 40% yield)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.27-7.32 (m, 4H), 7.43-7.46 (m, 2H), 7.49-7.59 (m, 4H) , 7.71-7.74 (m, 2H), 7.86-7.89 (m, 2H), 8.27-8.30 (m, 2H)
EI-MS (m / z): 411 (M ⁺ -1), CI-MS (m / z): 413 (MH ⁺ )
Elemental analysis theoretical value _{(C 28 H 16 N 2 O} 2)) C: 81.54%, H: 3.91%, N: 6.79%
Measured value C: 81.20%, H: 3.89%, N: 6.82%
[Absorption maximum: chloroform solution] 275 nm
[Fluorescence maximum wavelength: chloroform solution] 375 nm
Example 5

Synthesis of 2- (2 '-(3 "-fluorophenylethynyl) phenyl) benzoxazole (following formula (10))

To 20 ml Schlenk, 687 mg (2.0 mmol) of 2′-trifluoromethylsulfonyloxyphenylbenzoxazole, 23 mg (2.0 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 6 ml of piperidine were added and stirred. To this yellow reaction solution, 243 μl (2.1 mmol) of 3-fluorophenylacetylene was added and stirred at 80 ° C. for 1 hour. After completion of the reaction, a saturated aqueous ammonium chloride solution was added to the reaction mixture, the organic matter was extracted with methylene chloride, and the resulting organic layer was dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. The obtained reaction crude product is purified by column chromatography using silica gel (development solvent is gradually changed from hexane / ethyl acetate = 100/0 to 10/1) to obtain a yellow powder. The target compound was obtained. (400 mg, 64% yield)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 8.29-8.26 (m, 1H), 7.86-7.83 (m, 1H), 7.75-7.72 (m, 1H) , 7.64-7.60 (m, 1H), 7.53-7.50 (m, 2H), 7.42-7.31 (m, 5H), 7.12-7.02 (m, 1H)
EI-MS (m / z): 312 (M ⁺ -1), CI-MS (m / z): 314 (MH ⁺ )
[Absorption maximum: chloroform solution] 277 nm
[Fluorescence maximum wavelength: chloroform solution] 373 nm
Example 6

Synthesis of 2- (2 '-(4 "-phenylphenylethynyl) phenyl) benzoxazole (following formula (11))

To 20 ml Schlenk, 687 mg (2.0 mmol) of 2′-trifluoromethylsulfonyloxyphenylbenzoxazole, 23 mg (2.0 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 6 ml of piperidine were added and stirred. To this yellow reaction solution, 374 mg (2.1 mmol) of 4-phenylphenylacetylene was added and stirred at 80 ° C. for 1 hour. After completion of the reaction, a saturated aqueous ammonium chloride solution was added to the reaction mixture, the organic matter was extracted with methylene chloride, and the resulting organic layer was dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. By purifying the obtained reaction crude product by column chromatography using silica gel (developing solvent was gradually changed from hexane / ethyl acetate = 100/0 to 10/1 and further developed to 3/1), The target compound was obtained as a yellow powder. (460 mg, 62% yield)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 8.29-8.26 (m, 1H), 7.87-7.84 (m, 1H), 7.77-7.74 (m, 1H) , 7.71-7.61 (m, 7H), 7.53-7.37 (m, 7H)
EI-MS (m / z): 370 (M ⁺ -1), CI-MS (m / z): 372 (MH ⁺ )
[Absorption maximum: chloroform solution] 291 nm
[Fluorescence maximum wavelength: chloroform solution] 394 nm
Example 7

Synthesis of 2- (2 '-(2 "-methyl-2" -H-imidazolylethynyl) phenyl) benzoxazole (following formula (12))

To 20 ml Schlenk, 687 mg (2.0 mmol) of 2′-trifluoromethylsulfonyloxyphenylbenzoxazole, 23 mg (2.0 × 10 ⁻⁵ mol) of tetrakis (triphenylphosphine) palladium and 6 ml of piperidine were added and stirred. To this yellow reaction solution, 374 mg (2.1 mmol) of 5-ethynyl-1-methyl-1-H-imidazole was added and stirred at 80 ° C. for 1 hour. After completion of the reaction, a saturated aqueous ammonium chloride solution was added to the reaction mixture, the organic matter was extracted with methylene chloride, and the resulting organic layer was dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure. By purifying the obtained reaction crude product by column chromatography using silica gel (developing solvent was gradually changed from hexane / ethyl acetate = 100/0 to 10/1 and further developed to 3/1), The target compound was obtained as a yellow powder. (460 mg, 62% yield)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 8.25-8.22 (m, 1H), 7.77-7.70 (m, 2H), 7.61-7.57 (m, 1H) 7.55-7.46 (m, 3H), 7.42-7.37 (m, 3H), 3.88 (s, 3H)
EI-MS (m / z): 298 (M ⁺ -1), CI-MS (m / z): 300 (MH ⁺ )
[Absorption maximum: chloroform solution] 288 nm
[Fluorescence maximum wavelength: chloroform solution] 398 nm

Reference example 1
Synthesis of 2′-trifluoromethylsulfonylphenylbenzoxazole To a 200 ml reaction vessel was added 3.02 g (14 mmol) of 2′-hydroxyphenylbenzoxazole, 21 ml of methylene chloride and 2.6 ml (19 mmol) of triethylamine, and the mixture was stirred. The orange reaction solution was brought to 0 ° C. with an ice bath, and 2.7 ml (16 mmol) of trifluoromethanesulfonic anhydride was added dropwise. The reaction solution turned almost black was stirred for 4 hours while maintaining the reaction temperature at 0 ° C. After completion of the reaction, the reaction solution was diluted with 30 ml of methylene chloride, washed with water, hydrochloric acid with a concentration of 2 mol / L, and then with water, and dried over anhydrous magnesium sulfate. After filtration, the filtrate was dried under reduced pressure to obtain a crude product as a black oily substance. The crude product was purified by column chromatography using silica gel (development solvent was gradually changed from hexane / ethyl acetate = 100/0 to 3/1) to obtain a pale yellow powder. Further, the pale yellow powder was dissolved in hexane, and then cooled to -78 ° C to obtain the target compound as white fine crystals. (4.22 g, yield 87.1%)

¹ H-NMR (300 MHz, CDCl ₃ ) δ: 7.40-7.49 (m, 3H), 7.54-7.66 (m, 3H), 7.84 (m, 1H), 8.40 (D, 1H)
EI-MS (m / z): 343 (M ^<+> ), CI-MS (m / z): 344 (MH ^<+> ),
HRMS (High Resolution Mass Spectrometry)
Calculated value: 343.0126
Actual value: 343.0088
Example 8

Preparation of electroluminescent device containing bis (2- (benzoxazolyl) phenyl) acetylene (formula (2)) in the light emitting layer

A substrate obtained by vacuum-depositing a compound of indium oxide and tin oxide (hereinafter referred to as ITO) as a transparent electrode on soda glass was used as a substrate. N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′-diamine is deposited on the substrate by vapor deposition at a vacuum of 2 × 10 ⁻³ Pa or less. (Hereinafter referred to as TPD) 40 nm hole injection layer, TPD containing 1% by weight of bis (2- (benzoxazolyl) phenyl) acetylene 40 nm, tris (8-hydroxyquinolinate) An electroluminescent element was fabricated by forming an electron injection layer 20 nm composed of aluminum (hereinafter referred to as Alq ₃ ) and an aluminum (Al) electrode 100 nm. (See Figure 1)

The device emitted light at 60 cd / m ^{2 when} +25 V was applied between the electrodes using the ITO electrode as the positive electrode and the Al electrode as the negative electrode. The peak wavelength of the emission spectrum was 432 nm, and the chromaticity coordinates of the emission color according to JIS Z8701 were (0.33, 0.33).

Example 9
Preparation of an organic electroluminescence device containing 1,3-bis (2- (benzoxazolyl) phenylethynyl) benzene in an organic light emitting layer Transparent glass with an indium tin oxide (hereinafter abbreviated as ITO) film manufactured by ECH N, N′-diphenyl-N, N ′-(3-methylphenyl) is used as an electrode substrate, using a vacuum evaporation apparatus manufactured by ULVAC Kiko, with a vacuum degree of 2 × 10 ⁻³ Pa or less on the substrate. A hole injection layer 3 made of -1,1′-biphenyl-4,4′-diamine (hereinafter abbreviated as TPD) is formed to a thickness of 40 nm, 4,4′-bis (carbazol-9-yl) biphenyl (hereinafter referred to as “TPD”). The light-emitting layer 4 containing 10% by weight of 1,3-bis (2- (benzoxazolyl) phenylethynyl) benzene in CBP) is formed to a thickness of 20 nm, 3- (4-biphenylyl) -4-phen The hole blocking layer 5 made of ru-5-tert-butylphenyl-1,2,4-triazole (hereinafter abbreviated as TAZ) is 20 nm, and the electrode 6 is made of aluminum (Al) with a thickness of 100 nm and sequentially deposited by vacuum evaporation. A luminescence element was produced.
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.

When the ITO electrode 2 of the element is used as a positive electrode and the Al electrode 6 is used as a negative electrode and the voltage between the electrodes is increased, the element starts to emit light from the vicinity of +13 V, and is clearly 9 cd / m ² at +24 V. Emitted light. The chromaticity coordinates of the emission color were (0.18, 0.12). At this time, the efficiency of the current related to light emission was determined by the following equation.

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

  The current efficiency thus determined was 0.20 cd / A.

Example 10
Preparation of organic electroluminescent device containing 2- (2′-phenylethynylphenyl) benzoxazole in organic light emitting layer Light emitting layer 4 containing 11% by weight of 2- (2′-phenylethynylphenyl) benzoxazole in CBP was used. An electroluminescent element was produced in the same manner as Example 9 except for the above.
When the ITO electrode of the element was used as the positive electrode and the Al electrode was used as the negative electrode and the voltage between the electrodes was increased, the element started to emit light that was clearly visible to the naked eye from around +12 V, and emitted at 5 cd / m ² at +19 V. . The chromaticity coordinates of the emission color were (0.18, 0.10). The maximum current efficiency at this time was 0.12 cd / A.

Example 11
Preparation of an organic electroluminescence device containing 1,4-bis (2 ′-(benzoxazolyl) phenylethynyl) benzene in an organic light emitting layer 1,4-bis (2 ′-(benzoxazolyl) phenyl in CBP An electroluminescent device was produced in the same manner as in Example 9, except that the light emitting layer 4 containing 8% by weight of ethynyl) benzene was used.
When the ITO electrode of the element was used as the positive electrode and the Al electrode was used as the negative electrode and the voltage between the electrodes was increased, the element started to emit light that was clearly visible to the naked eye from around +8 V, and emitted at 31 cd / m ² at +15 V. . The chromaticity coordinates of the emission color were (0.16, 0.13). This device showed a maximum current efficiency of 0.11 cd / A at an interelectrode voltage of + 14V.

Example 12
Preparation of an organic electroluminescent device containing 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzoxazole in an organic light emitting layer 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzo in CBP An electroluminescent element was produced in the same manner as in Example 9 except that the light emitting layer 4 containing 9% by weight of oxazole was used with a film thickness of 30 nm and the hole blocking layer 5 made of TAZ with a film thickness of 30 nm. When the voltage between the electrodes was increased by energizing with the positive electrode and the Al electrode as the negative electrode, the device started to emit light with a naked eye from around + 10V, and emitted at 24 cd / m ² at + 20V. The chromaticity coordinates of the emission color were (0.17, 0.13). This device showed a maximum current efficiency of 0.11 cd / A at an interelectrode voltage of + 18V.

Example 13
Preparation of an organic electroluminescent device containing 2- (2 ′-(2 ″ -methyl-2 ″ -H-imidazolylethynyl) phenyl) benzoxazole in an organic light emitting layer 2- (2 ′-(2 ″ -methyl) in CBP An electroluminescent device was produced in the same manner as in Example 12 except that the light-emitting layer 4 containing 10% by weight of -2 "-H-imidazolylethynyl) phenyl) benzoxazole was used.
When the ITO electrode of the element was used as the positive electrode and the Al electrode was used as the negative electrode and the voltage between the electrodes was increased, the element started to emit light that was clearly visible to the naked eye from around +8 V, and emitted at 16 cd / m ² at +20 V. . The chromaticity coordinates of the emission color were (0.16, 0.14). This device showed a maximum current efficiency of 0.23 cd / A at an interelectrode voltage of + 16V.

Example 14
Preparation of an organic electroluminescent device containing 2- (2 ′-(4 ″ -phenylphenylethynyl) phenyl) benzoxazole in an organic light emitting layer 2- (2 ′-(4 ″ -phenylphenylethynyl) phenyl) benzo in CBP A light emitting layer 4 containing 10% by weight of oxazole is used, and an electron injection layer 7 made of tris (8-hydroxyquinolinato) aluminum (hereinafter abbreviated as Alq ₃ ) is formed between the hole blocking layer 5 and the Al electrode 6. An electroluminescent element was produced in the same manner as in Example 12 except that the film was inserted at 30 nm (see FIG. 2).
When the voltage between the electrodes was increased by energizing with the ITO electrode of the element as the positive electrode and the Al electrode as the negative electrode, the element started to emit light with a naked eye from around + 10V, and emitted at 58 cd / m ² at + 19V. . The chromaticity coordinates of the emission color were (0.16, 0.13). This device showed a maximum current efficiency of 0.27 cd / A at an interelectrode voltage of + 16V.

Example 15
Preparation of organic electroluminescence device containing 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzoxazole in the organic light emitting layer (2)
An electroluminescent device was produced in the same manner as in Example 14 except that the light-emitting layer 4 containing 9% by weight of 2- (2 ′-(3 ″ -fluorophenylethynyl) phenyl) benzoxazole in CBP was used.
When the ITO electrode of the element was used as a positive electrode and the Al electrode was used as a negative electrode and the voltage between the electrodes was increased, the element started to emit light with a naked eye from around +9 V, and emitted at 46 cd / m ² at +23 V. . The chromaticity coordinates of the emission color were (0.17, 0.13). This device showed a maximum current efficiency of 0.23 cd / A at an interelectrode voltage of + 16V.

Example 16
Preparation of an organic electroluminescent device containing 2- (2 ′-(2 ″ -methyl-2 ″ -H-imidazolylethynyl) phenyl) benzoxazole in an organic light emitting layer 2- (2 ′-(2 ″ -methyl) in CBP An electroluminescent device was produced in the same manner as in Example 14 except that the light-emitting layer 4 containing 10% by weight of -2 "-H-imidazolylethynyl) phenyl) benzoxazole was used.
When the ITO electrode of the element was used as a positive electrode and the Al electrode was used as a negative electrode and the voltage between the electrodes was increased, the element started to emit light that was clearly visible to the naked eye from around +10 V, and emitted at 42 cd / m ² at +26 V. . This device showed a maximum current efficiency of 0.31 cd / A at an interelectrode voltage of + 25V.

The present invention provides an organic electroluminescence device containing a heterocyclic-substituted phenylacetylene compound represented by the above formula (1) which exhibits strong blue light emission under ultraviolet irradiation in an organic compound thin layer.
The present invention also provides a heterocyclic substituted phenylacetylene compound represented by the above formula (1), which exhibits strong blue light emission by irradiation with ultraviolet rays in a chloroform solution and is extremely useful as an organic electroluminescence device material, and a method for producing the same.

FIG. 1 is a cross-sectional view of organic EL elements in Examples 8 to 13, in which reference numeral 1 indicates a glass substrate, 2 indicates ITO (anode), 3 indicates a hole (hole) injection layer, 4 represents a light emitting layer, 5 represents an electron injection layer or hole blocking layer, and 6 represents an Al electrode (cathode). FIG. 2 is a cross-sectional view of the organic EL elements in Examples 14 to 16, in which reference numeral 1 indicates a glass substrate, 2 indicates ITO (anode), 3 indicates a hole (hole) injection layer, 4 represents a light emitting layer, 5 represents a hole block layer, 6 represents an Al electrode (cathode), and 7 represents an electron injection layer.

Claims (11)

The following formula (1):

In the formula, n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group, When n ¹ is 2 or 3, A represents a divalent or trivalent aryl group or heterocyclic group, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, and X represents O or S N ² represents an integer of 1 to 4;
A heterocyclic substituted phenylacetylene compound represented by the formula: The compound represented by formula (1) is represented by the following formula (2):

In the formula, R ² represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group.
The heterocycle-substituted phenylacetylene compound according to claim 1, which is represented by the formula: The compound represented by the formula (1) is represented by the following formula (3):

In the formula, n ³ represents an integer of 2 to ³ .
The heterocycle-substituted phenylacetylene compound according to claim 1, which is represented by the formula: The compound represented by formula (1) is represented by the following formula (4):

The heterocycle-substituted phenylacetylene compound according to claim 1, which is represented by the formula: Using a zerovalent palladium compound as a catalyst, the following formula (5):

In the formula, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, X represents O or S, and n ² represents an integer of 1 to 4.
A heterocyclic-substituted phenyl trifluoromethanesulfonate compound represented by the following formula (6):

In the formula, n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group, when n ¹ is 2 or 3, A represents a divalent or trivalent aryl group or heterocyclic group;
The terminal acetylene compound represented by the following formula (1) is reacted in a basic solvent:

In the formula, A, R ¹ , X, n ¹ and n ² are as defined above.
The manufacturing method of the heterocyclic substituted phenylacetylene compound shown by these.   The method for producing a heterocyclic-substituted phenylacetylene compound according to claim 5, wherein the zero-valent palladium compound is a zero-valent palladium phosphine complex or a zero-valent palladium olefin complex.   6. The method for producing a heterocyclic-substituted phenylacetylene compound according to claim 5, wherein the basic solvent is piperidine or pyrrolidine. An organic electroluminescence device having an organic compound thin layer between a pair of electrodes, wherein the organic compound thin layer is represented by the following formula (1):

In the formula, n ¹ represents an integer of ¹ to 3, and when n ¹ is 1, A represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group, When n ¹ is 2 or 3, A represents a divalent or trivalent aryl group or heterocyclic group, R ¹ represents an alkyl group, a haloalkyl group, an alkoxy group, or a haloalkoxy group, and X represents O or S N ² represents an integer of 1 to 4;
The organic electroluminescent element characterized by containing the heterocyclic substituted phenylacetylene compound shown by these. The compound represented by formula (1) is represented by the following formula (2):

In the formula, R ² represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylsilyl group, or a heterocyclic group.
The organic electroluminescent device according to claim 8, which is a heterocyclic substituted phenylacetylene compound represented by the formula: The compound represented by the formula (1) is represented by the following formula (3):

In the formula, n ³ represents an integer of 2 to ³ .
The organic electroluminescent device according to claim 8, which is a heterocyclic substituted phenylacetylene compound represented by the formula: The compound represented by formula (1) is represented by the following formula (4):

The organic electroluminescent device according to claim 8, which is a heterocyclic substituted phenylacetylene compound represented by the formula:

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