Method for synthesizing organic metal complex and organic electroluminescent element using compound synthesized by said synthesis method

Abstract

A method for synthesizing an organic metal complex having a substituent capable of coordinating to a central metal ion includes replacing substituents RX and RX in an organic metal complex having a structure represented by general formula (2) with substituents RB and RB in an organic metal complex having a structure represented by general formula (1), respectively: ##STR00001##

Claims

1. A method for synthetizing an organic metal complex having a structure represented by Formula (1), the method comprising: replacing substituents RX and RX in an organic metal complex having a structure represented by Formula (2) with substituents RB and RB, respectively, in an organic metal complex having a structure represented by Formula (1): ##STR00063## wherein the ring formed by A.sub.11 to A.sub.16 is a benzene ring, a pyridine ring, or a pyrimidine ring; A.sub.11 forms a covalent bond with a central metal M; the ring formed by B.sub.11 to B.sub.15 is an imidazole ring; B.sub.11 forms a coordination bond with the central metal M; Ra represents a substituent and p represents an integer of 0 to 4; Rb represents a substituent and q represents an integer of 0 to 3; if two or more Ra's are present, Ra's may be identical to or different from one another; if two or more Rb's are present, Rb's may be identical to or different from one another; RB and RB each independently represent a hydroxy group, an amino group optionally substituted by an alkyl or aryl group, a cyano group, a pyridyl group, a pyrimidyl group, a pyrazyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a thiol group, a sulfide group, or a phosphino group optionally substituted by an alkyl or aryl group; r represents an integer of 1 or more, r represents an integer of 0 or more, and p, q, r, and r satisfy the following relations: 0<p+r4 and 1q+r3; M represents iridium or platinum; L represents a monoanionic bidentate ligand; and n represents an integer of 1 to 3, m represents an integer of 0 to 2, and the sum of m and n is 2 or 3; ##STR00064## wherein RX and RX respectively represent substituents replaceable with RB and RB, and each of RX and RX is a halogen atom, a sulfonyloxy group, a carboxy group, a formyl group, or a carbamoyl group; A.sub.11 to A.sub.16, B.sub.11 to B.sub.15, Ra, p, Rb, q, r, r, M, L, n, and m are the same as those defined in Formula (1); and the positions of Ra, Rb, RB, and RB in Formula (1) are the same as those of Ra, Rb, RX, and RX, respectively, in Formula (2).

2. The method for synthetizing an organic metal complex according to claim 1, wherein each of RB and RB in Formula (1) represents the pyridyl group, the pyrimidyl group, the pyrazyl group, the pyrazolyl group, the imidazolyl group, the triazolyl group, the cyano group, or the thiol group.

3. The method for synthetizing an organic metal complex according to claim 2, wherein RB or RB in Formula (1) is the cyano group.

4. The method for synthetizing an organic metal complex according to claim 1, wherein the position of the substituent RB in Formula (1) is B.sub.15, and the position of the substituent RX in Formula (1) is B.sub.15.

5. The method for synthetizing an organic metal complex according to claim 1, wherein B.sub.11 is a nitrogen atom.

6. The method for synthetizing an organic metal complex according to claim 1, wherein the ring formed by A.sub.11 to A.sub.16 in Formula (1) is a benzene ring.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a graph illustrating the correlation between the emission wavelength and emission lifetime of an Ir complex having a phenylpyridine ligand.

EMBODIMENTS TO CARRY OUT THE INVENTION

(2) The method for synthesizing an organic metal complex of the present invention includes replacing substituents RX and RX in an organic metal complex having a structure represented by Formula (2) described later with substituents RB and RB, respectively, in an organic metal complex having a structure represented by Formula (1) described later. These technical characteristics are common in claims 1 to 8 of the present invention.

(3) In an embodiment of the present invention, each of RB and RB in Formula (1) preferably includes any one of a group having a carbon-nitrogen double bond (CN), a cyano group, and a thiol group, more preferably a cyano group. In another embodiment, the ring formed by B.sub.11 to B.sub.15 in Formula (1) (and (2)) is preferably an imidazole, pyrazole, or triazole ring. The embodiments are effective for adjustment of chromaticity; i.e., shortening of emission wavelength by the electronic effects of the substituents.

(4) Each of RX and RX in Formula (2) is preferably a halogen atom, a sulfonyloxy group, a carboxy group, a formyl group, or a carbamoyl group in view of ease of synthesis of an organic metal complex having a structure represented by Formula (1).

(5) A compound synthesized by the method of the present invention is suitable for use in an organic electroluminescent element.

(6) The present invention, the contexture thereof, and embodiments and aspects for implementing the present invention will now be described in detail. As used herein, the term to between two numerical values indicates that the numeric values before and after the term are inclusive as the lower limit value and the upper limit value, respectively.

(7) <<Organic Metal Complex Having Structure Represented by Formula (1)>>

(8) The organic metal complex according to the present invention has a structure represented by following Formula (1).

(9) ##STR00007##

(10) In Formula (1), the ring formed by A.sub.11 to A.sub.16 is an aromatic hydrocarbon ring or a heteroaromatic ring. A.sub.11 to A.sub.16 each independently represent a carbon or nitrogen atom. A.sub.11 forms a covalent bond with a central metal M. The ring formed by B.sub.11 to B.sub.15 is a heteroaromatic ring. B.sub.11 and B.sub.12 each independently represent a carbon or nitrogen atom, B.sub.13 to B.sub.15 each independently represent a carbon, nitrogen, or oxygen atom, and at least two of B.sub.11 to B.sub.15 are a nitrogen atom. B.sub.11 forms a coordination bond with the central metal M. Ra represents a substituent and p represents an integer of 0 to 4. Rb represents a substituent and q represents an integer of 0 to 3. If two or more Ra's are present, Ra's may be identical to or different from one another. If two or more Rb's are present, Rb's may be identical to or different from one another. Ra's may be bonded together to form a ring structure, and Rb's may be bonded together to form a ring structure. Ra and Rb may be bonded together to form a ring structure. RB and RB each independently represent a hydroxy group or a substituent containing a nitrogen, sulfur, or phosphorus atom having a lone pair. In Formula (1), r and r each independently represent an integer of 0 or more and satisfy the relation: r+r1, and p, q, r, and r satisfy the following relations: 0p+r4 and 0q+r3. M represents iridium or platinum and L represents a monoanionic bidentate ligand. In Formula (1), n represents an integer of 1 to 3, m represents an integer of 0 to 2, and the sum of m and n is 2 or 3.

(11) Examples of the aromatic hydrocarbon ring or heteroaromatic ring formed by A.sub.11 to A.sub.16 include benzene, naphthalene, anthracene, benzofuran, benzothiophene, indole, carbazole, dibenzofuran, dibenzothiophene, pyridine, pyrimidine, pyrazine, and pyridazine rings.

(12) Examples of the heteroaromatic ring formed by B.sub.11 to B.sub.15 include imidazole, pyrazole, triazole, oxazole, thiazole, benzimidazole, and benzothiazole rings. Preferred are imidazole, pyrazole, and triazole rings.

(13) The substituent represented by Ra or Rb may be any substituent that does not inhibit the functions of the compound according to the present invention. Examples of the substituent include deuterium and halogen atoms, and cyano, alkyl, alkenyl, alkynyl, carbonyl, amino, silyl, hydroxy, thiol, phosphine oxide, aromatic hydrocarbon, heteroaromatic, non-aromatic hydrocarbon, non-aromatic heterocyclic, phosphino, sulfonyl, and nitro groups. Such a substituent may further have any substituent. For example, the substituent may be an alkoxy group prepared through substitution of a hydroxy group by an alkyl group.

(14) If Ra's and Rb's are present, the Ra's and Rb's may be bonded together to form a ring structure. Examples of the ring structure include imidazophenanthridine.

(15) RB and RB each independently represent a hydroxy group or a substituent containing a nitrogen, sulfur, or phosphorus atom having a lone pair.

(16) Examples of the substituent containing a nitrogen atom having a lone pair include an amino group, a cyano group, and a group having a CN double bond. The amino group may be substituted by an alkyl or aryl group. Examples of the group having a CN double bond include heteroaromatic groups, such as pyridyl, pyrimidyl, pyrazyl, pyrazolyl, imidazolyl, and triazolyl groups.

(17) Examples of the substituent containing a sulfur atom having a lone pair include thiol (or mercapto) and sulfido groups.

(18) Examples of the substituent containing a phosphorus atom having a lone pair include a phosphino group. The phosphino group may be substituted by an alkyl or aryl group.

(19) RB or RB preferably includes any one of a group having a CN double bond, a cyano group, and a thiol group, more preferably a cyano group.

(20) Examples of the organic metal complex having a structure represented by Formula (1) include, but are not limited to, the following compounds:

(21) ##STR00008## ##STR00009## ##STR00010## ##STR00011## ##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032##

(22) <<Organic Metal Complex Having Structure Represented by Formula (2)>>

(23) The organic metal complex having a structure represented by Formula (1) described above is synthesized through replacement of RX and RX in an organic metal complex having a structure represented by Formula (2) described below.

(24) ##STR00033##

(25) In Formula (2), RX and RX represent substituents replaceable with RB and RB, respectively. A.sub.11 to A.sub.16, B.sub.11 to B.sub.15, Ra, p, Rb, q, r, r, M, L, n, and m are the same as those defined in Formula (1). The positions of Ra, Rb, RB, and RB in Formula (1) are the same as those of Ra, Rb, RX, and RX, respectively, in Formula (2).

(26) RX or RX in Formula (2) is a substituent replaceable with RB or RB, respectively. The substituent replaceable with RB or RB may be any substituent that can be replaced by any known synthetic process, such as substitution or addition reaction. The substituent replaceable with RB or RB is, for example, a group corresponding to a conjugate base of an acid having a pKa of 15 or less in water.

(27) Preferred examples of the substituent replaceable with RB or RB include halogen atoms (e.g., chlorine, bromine, and iodine atoms), sulfonyloxy groups (e.g., trifluoromethanesulfonyl, methanesulfonyl, p-toluenesulfonyl, and p-chlorobenzenesulfonyl groups), aryloxy groups (e.g., phenoxy and p-nitrophenoxy groups), and acyloxy groups (e.g., acetyl, trifluoroacetyl, and m-chlorobenzoyloxy groups).

(28) Other preferred examples of the substituent RX or RX replaceable with RB or RB include groups represented by COA (where A represents a hydrogen atom or a hydroxy, alkoxy, or amino group), and a hydroxyliminomethyl group prepared through the reaction between aldehyde and hydroxylamine.

(29) Among these substituents, more preferred are halogen atoms and sulfonyloxy, carboxy, formyl, and carbamoyl groups.

(30) In Formula (1) or (2), the position of the substituent RB or RX is preferably B.sub.14 or B.sub.15.

(31) Examples of the organic metal complex having a structure represented by Formula (2) include, but are not limited to, the following compounds:

(32) ##STR00034## ##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052##

(33) The organic metal complex having a structure represented by Formula (2) can be synthesized by any known synthetic process, such as a process disclosed in WO07/097149.

(34) <<Synthesis of Organic Metal Complex>>

(35) The organic metal complex having a structure represented by Formula (1) can be synthesized from the organic metal complex having a structure represented by Formula (2) through any reaction process, such as a cross-coupling process involving reaction between an organic halide (RX) and an organic metal compound (R-M) in the presence of a palladium (Pd) or nickel (Ni) catalyst to form a carbon-carbon (or nitrogen) bond. Examples of the coupling reaction include the Tamao-Kumada-Corriu reaction described in, for example, J. Am. Chem. Soc., 94, 4374 (1972) and Bull. Chem. Soc. Jpn., 49, 1958 (1976); the Negishi reaction described in, for example, J. Org. Chem., 42, 1821 (1977); the Kosugi-Migita-Stille reaction described in J. Organomet. Chem., 653, 50 (2002); the Suzuki-Miyaura reaction described in Chem. Rev., 95, 2457 (1995); the Hiyama reaction described in J. Org. Chem., 53, 918 (1988); and the Buchwald-Hartwig reaction described in, for example, Angew. Chem. Int. Ed. Engl., 34, 1348 (1995), Acc. Chem. Res., 31, 805 (1998), and Acc. Chem. Res., 31, 851 (1998).

(36) These reactions each involve the use of a reagent for conversion of the organic metal complex having a structure represented by Formula (2) into the organic metal complex having a structure represented by Formula (1). The reagent is used in an amount of n100% to n3000% relative to the molar amount (n) of the organic metal complex having a structure represented by Formula (2) with reference to the documents described above.

(37) The solvent used in the synthetic method can be appropriately selected depending on the type of the coupling reaction with reference to the documents described above.

(38) The synthetic method of the present invention may involve the use of a palladium or nickel catalyst in an amount of n0.1% to n100% relative to the molar amount (n) of the organic metal complex having a structure represented by Formula (2) with reference to the documents described above.

(39) The synthetic method may involve the coupling reaction using metallic copper or monovalent copper ion and an appropriate ligand described in Ullmann, F., Bielecki, J. Ber. Dtsch. Chem. Ges. 1901, 34, 2174, J. Org. Chem. 69, 5578 (2004).

(40) The synthetic method involves the use of a reagent in this coupling reaction for conversion of the organic metal complex having a structure represented by Formula (2) into the organic metal complex having a structure represented by Formula (1). The reagent is used in an amount of n100% to n3000% relative to the molar amount (n) of the organic metal complex having a structure represented by Formula (2) with reference to the documents described above.

(41) The solvent used in the coupling reaction can be appropriately selected with reference to the documents described above.

(42) The copper compound may be used in the coupling reaction in an amount of n0.1% to n1000% relative to the molar amount of the organic metal complex having a structure represented by Formula (2) with reference to the documents described above.

(43) In the case that RB or RB in Formula (1) is a cyano group, the synthetic method may involve a traditional conversion process of an aldehyde oxime or a carbamoyl group into a cyano group through intramolecular dehydration, or the reaction between an organic halide and a metal cyanide disclosed in Japanese Translation of PCT International Application Publication No. 2006-513278.

(44) The synthetic method of the present invention may involve the use of a reagent for the reaction in an amount of n100% to n3000% relative to the molar amount (n) of the organic metal complex having a structure represented by Formula (2) with reference to the document described above.

(45) The synthetic method involves the use of an aprotic solvent. Examples of the solvent include nitriles, such as acetonitrile, propionitrile, and benzonitrile; N,N-dialkyl amides, such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidinone; sulfoxides, such as dimethyl sulfoxide; sulfones, such as dimethylsulfone and sulfolane; and substituted and unsubstituted aromatic hydrocarbons, such as benzene, toluene, xylene, mesitylene, o-dichlorobenzene, and anisole.

(46) In the synthetic method of the present invention, the reaction temperature is 60 to 200 C., preferably 80 to 180 C., particularly preferably 90 to 170 C.

(47) A compound synthesized by the method of the present invention can be purified by any purification technique (e.g., recrystallization, chromatography, or sublimation) for achieving a purity suitable for use in an organic EL element.

(48) <<Layer Configuration of Organic EL Element>>

(49) The organic metal complex of the present invention having a structure represented by Formula (1) is suitable for use in an organic EL element.

(50) Typical examples of the configuration of the organic EL element include, but are not limited to, the following configurations.

(51) (i) Anode/luminous layer/cathode

(52) (ii) Anode/luminous layer/electron transporting layer/cathode

(53) (iii) Anode/hole transporting layer/luminous layer/cathode

(54) (iv) Anode/hole transporting layer/luminous layer/electron transporting layer/cathode

(55) (v) Anode/hole transporting layer/luminous layer/electron transporting layer/electron injecting layer/cathode

(56) (vi) Anode/hole injecting layer/hole transporting layer/luminous layer/electron transporting layer/cathode

(57) (vii) Anode/hole injecting layer/hole transporting layer/(electron blocking layer)/luminous layer/(hole blocking layer)/electron transporting layer/electron injecting layer/cathode

(58) Among the aforementioned configurations, configuration (vii) is preferred, but any other configuration may be used.

(59) The luminous layer is composed of a single layer or a plurality of sublayers. A luminous layer composed of a plurality of luminous sublayers may include a non-luminous intermediate sublayer between the luminous sublayers.

(60) A hole blocking layer (also referred to as hole barrier layer) or an electron injecting layer (also referred to as cathode buffer layer) may optionally be disposed between the luminous layer and the cathode. An electron blocking layer (also referred to as electron barrier layer) or a hole injecting layer (also referred to as anode buffer layer) may be disposed between the luminous layer and the anode.

(61) The electron transporting layer, which has a function of transporting electrons, encompasses the electron injecting layer and the hole blocking layer in a broad sense. The electron transporting layer may be composed of a plurality of sublayers.

(62) The hole transporting layer, which has a function of transporting holes, encompasses the hole injecting layer and the electron blocking layer in a broad sense. The hole transporting layer may be composed of a plurality of sublayers.

(63) In the typical configurations described above, any of the layers other than the anode and the cathode may also be referred to as organic layer.

(64) The organic EL element may have a tandem structure including a plurality of luminous units each including at least one luminous layer.

EXAMPLES

(65) The present invention will now be described in detail by way of Examples, which should not be construed to limit the invention.

Example 1

(66) <<Synthesis of Organic Metal Complex>>

(67) (1) Synthesis of Exemplary Compound 1-10

(68) Exemplary compound 1-10 was synthesized from exemplary compound 2-7 through the following procedure.

(69) ##STR00053##

(70) Exemplary compound 2-7 (1.21 g, 1.0 mmol), zinc cyanide (0.47 g, 4.0 mmol), bis(dibenzylideneacetone)palladium (Pd(dba)) (29 mg, 0.048 mmol), and tri-t-butylphosphine (30 mg, 0.15 mmol) were agitated in N,N-dimethylformamide (DMF) (30 mL) while being heated at 90 C. for four hours. The reaction mixture was left to cool, and insoluble matter was then separated through filtration. Water was added to the filtrate, and the mixture was subjected to extraction with ethyl acetate. The organic phase was repeatedly washed with water and dried over anhydrous magnesium sulfate. The solvent was removed through evaporation under reduced pressure, and the resultant concentrate was purified by silica gel column chromatography. An eluate containing the target product was concentrated under reduced pressure, and the concentrate was suspended in methanol, followed by filtration and drying, to prepare exemplary compound 1-10 (0.75 g, yield: 71%).

(71) Exemplary compound 1-10 was identified through analysis by mass spectrometry (MS) and nuclear magnetic resonance (.sup.1H-NMR) spectroscopy.

(72) The (.sup.1H-NMR) Spectroscopic Results are as Follows:

(73) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): (ppm vs. TMS)=7.32 (s, 3H), 7.13 (s, 3H), 7.05 (s, 3H), 7.32 (s, 3H), 6.63-6.59 (m, 3H), 6.54-6.48 (m, 2H), 6.33-6.31 (m, 3H), 2.41 (s, 9H), 2.24 (s, 9H), 1.76 (s, 9H)

(74) (2) Synthesis of Exemplary Compound 1-10

(75) Exemplary compound 1-10 was synthesized from exemplary compound 2-13 through the following procedure.

(76) ##STR00054##

(77) Exemplary compound 2-13 (0.50 g, 0.47 mmol) was suspended in methanol (100 mL) in a nitrogen atmosphere. Hydroxylamine hydrochloride (0.20 g) and triethylamine (0.3 g, 2.9 mmol) were added to the suspension, and the mixture was agitated while being heated at 50 C. for two hours. The reaction mixture was concentrated under reduced pressure, and the resultant solid was washed with water and then with methanol, followed by drying. Acetic anhydride (5 mL) and tetrahydrofuran (THF) (10 mL) were added to the solid, and the mixture was heated under reflux for 10 hours. The reaction mixture was concentrated under reduced pressure, and the resultant solid was washed with water and then with methanol, followed by purification by silica gel column chromatography, to prepare exemplary compound 1-10 (0.29 g, yield: 58%).

(78) Exemplary compound 1-10 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(79) (3) Synthesis of Exemplary Compound 1-10 by Traditional Synthetic Method

(80) Exemplary compound 1-10 was attempted to be synthesized from comparative compound 1 through the following procedure.

(81) ##STR00055##

(82) Comparative compound 1 (1.0 g, 3.48 mmol) and iridium acetate (0.13 g, 0.35 mmol) were suspended in ethylene glycol (20 mL) in a nitrogen atmosphere, and the suspension was heated at 160 C. for eight hours. The reaction mixture was a brown solution.

(83) The reaction mixture was analyzed by high-performance liquid chromatography, but exemplary compound 1-10 was not detected at all.

(84) (4) Synthesis of Exemplary Compound 1-37

(85) Exemplary compound 1-37 was synthesized from exemplary compound 2-10 through the following procedure.

(86) ##STR00056##

(87) Exemplary compound 2-10 (268 mg, 0.2 mmol) and 3-pyridylboronic acid (100 mg, 0.8 mmol) were dissolved in dioxane (20 mL) in a nitrogen atmosphere. Sodium carbonate (200 mg), water (5 mL), and tetrakis(triphenylphosphine)palladium (50 mg) were added to the solution, and the mixture was heated under reflux for six hours. The reaction mixture was left to cool and then subjected to extraction with ethyl acetate. The organic phase was repeatedly washed with water, and the solvent was removed through evaporation under reduced pressure. The resultant concentrate was purified by silica gel column chromatography, to prepare exemplary compound 1-37 (179 mg, yield: 67%).

(88) Exemplary compound 1-37 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(89) (5) Synthesis of Exemplary Compound 1-58

(90) Exemplary compound 1-58 was synthesized from exemplary compound 2-43 through the following procedure.

(91) ##STR00057##

(92) Exemplary compound 2-43 (4.56 g, 5.0 mmol) and copper (I) cyanide (2.69 g, 30.0 mmol) were reacted in N,N-dimethylacetamide (DMA) (90 mL) in a nitrogen atmosphere at 150 C. for 45 hours. The reaction mixture was left to cool, and insoluble matter was then separated through filtration. Water was added to the filtrate, and the mixture was subjected to extraction with ethyl acetate. The organic phase was repeatedly washed with water, and the solvent was removed through evaporation under reduced pressure. The resultant concentrate was purified by silica gel column chromatography, to prepare exemplary compound 1-58 (2.14 g, yield: 57%).

(93) Exemplary compound 1-58 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(94) (6) Synthesis of Exemplary Compound 1-85

(95) Exemplary compound 1-85 was synthesized from exemplary compound 2-72 through the following procedure.

(96) ##STR00058##

(97) Exemplary compound 2-72 (1.66 g, 1.0 mmol), zinc cyanide (1.06 g, 9.0 mmol), bis(dibenzylideneacetone)palladium (60 mg, 0.1 mmol), tri-t-butylphosphine (61 mg, 0.3 mmol), and zinc powder (40 mg, 0.6 mmol) were agitated in N-methylpyrrolidone (NMP) (50 mL) in a nitrogen atmosphere while being heated at 160 C. for four hours. The reaction mixture was left to cool, and insoluble matter was separated through filtration. Water was added to the filtrate, and the mixture was subjected to extraction with ethyl acetate. The organic phase was repeatedly washed with water and dried over anhydrous magnesium sulfate. The solvent was removed through evaporation under reduced pressure, and the resultant concentrate was purified by silica gel column chromatography. An eluate containing the target product was concentrated under reduced pressure, and the concentrate was suspended in methanol, followed by filtration and drying, to prepare exemplary compound 1-85 (0.51 g, yield: 45%).

(98) Exemplary compound 1-85 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(99) (7) Synthesis of Exemplary Compound 1-97

(100) Exemplary compound 1-97 was synthesized from exemplary compound 2-7 through the following procedure.

(101) ##STR00059##

(102) (7.1) Synthesis of Intermediate A

(103) Bromodimethylsulfonium bromide (100 mg, 0.45 mmol) and ammonium thiocyanate (114 mg, 1.5 mmol) were suspended in acetonitrile (50 mL). Exemplary compound 2-7 (122 mg, 0.10 mmol) was added to the suspension, and the mixture was agitated at room temperature (25 C.) for three hours. The reaction mixture was added to saturated aqueous sodium hydrogen carbonate solution (100 mL), and the precipitated solid was separated through filtration and washed with methylene chloride. The methylene chloride phase was washed with water and dried over anhydrous magnesium sulfate. The solvent was then removed through evaporation under reduced pressure. The resultant solid was purified by silica gel column chromatography, to prepare intermediate A (104 mg, yield: 91%).

(104) (7.2) Synthesis of Exemplary Compound 1-97

(105) Intermediate A (100 mg, 0.0871 mmol) was dissolved in THF (15 mL) and lithium aluminum hydride (50 mg, 1.32 mmol) was added to the solution, and the mixture was allowed to stand at 5 C. or lower for two hours. An aqueous ammonium chloride solution was added to the reaction mixture, and the mixture was subjected to extraction with methylene chloride. The organic phase was washed with water and dried over anhydrous magnesium sulfate. The solvent was removed through evaporation under reduced pressure, and the residue was purified by silica gel column chromatography, to prepare exemplary compound 1-97 (72 mg, yield: 72%).

(106) Exemplary compound 1-97 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(107) (8) Synthesis of Compound 1-30

(108) Exemplary compound 1-30 was synthesized from exemplary compound 2-23 through the following procedure.

(109) ##STR00060##

(110) Exemplary compound 2-23 (268 mg, 0.2 mmol) and copper (I) cyanide (143 mg, 1.6 mmol) were reacted in NMP (5 mL) at 150 C. for 60 hours. The reaction mixture was left to cool, and insoluble matter was then separated through filtration. Water was added to the filtrate, and the mixture was subjected to extraction with ethyl acetate. The organic phase was repeatedly washed with water, and the solvent was removed through evaporation under reduced pressure. The resultant concentrate was purified by silica gel column chromatography, to prepare exemplary compound 1-30 (158 mg, yield: 67%).

(111) Exemplary compound 1-30 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(112) (9) Synthesis of Exemplary Compound 1-29

(113) Exemplary compound 1-29 was synthesized from exemplary compound 2-12 through the following procedure.

(114) ##STR00061##

(115) (9.1) Synthesis of Intermediate B

(116) Exemplary compound 2-12 (301 mg, 0.2 mmol) was suspended in a solution (10 mL) of ammonia in methanol (7 mol/L) and the mixture was agitated at room temperature (25 C.) for 12 hours. The reaction mixture was subjected to filtration, to prepare intermediate B (277 mg, yield: 95%).

(117) (9.2) Synthesis of Exemplary Compound 1-29

(118) Intermediate B (270 mg, 0.185 mmol) was suspended in toluene (5 mL) and diphosphorus pentoxide (270 mg, 1.9 mmol) was added to the suspension, and the mixture was heated under reflux for four hours. Water was added to the reaction mixture, and the mixture was vigorously agitated. The solid was then separated from the reaction mixture through filtration and washed with methanol, to prepare exemplary compound 1-29 (208 mg, yield: 80%).

(119) Exemplary compound 1-29 was identified through analysis by mass spectrometry (MS) and .sup.1H-NMR spectroscopy as described in procedure (1) described above.

(120) As described above, organic metal complexes that cannot be synthesized by traditional methods can be synthesized by the method of the present invention at high yield.

Example 2

(121) Indium tin oxide (ITO) was formed into a thickness of 150 nm on a glass substrate (50 mm by 50 mm, thickness: 0.7 mm), and then patterned into an anode. Subsequently, the transparent substrate having the ITO transparent electrode was ultrasonically washed with isopropyl alcohol, dried with dry nitrogen gas, and cleaned with UV ozone for five minutes. The transparent substrate was then fixed onto a substrate holder of a commercially available vacuum deposition system.

(122) Poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT/PSS, Baytron P A1 4083, manufactured by Bayer) was diluted with pure water to prepare a solution. The solution was applied to the transparent substrate through slit coating and then dried at 140 C. for one hour, to form a hole injecting layer having a thickness of 50 nm.

(123) Materials for layers were placed in vapor deposition crucibles in the vacuum deposition system in amounts suitable for preparation of an organic EL element. The crucibles were composed of molybdenum or tungsten; i.e., a material for resistance heating.

(124) Subsequently, the substrate was placed in the vacuum deposition system without being exposed to air, and the system was evacuated to a vacuum of 110.sup.4 Pa. -NPD illustrated below was deposited onto the substrate at a deposition rate of 0.1 nm/second, to form a hole transporting layer having a thickness of 70 nm.

(125) Compound H-1 (illustrated below) and exemplary compound 1-10 were co-deposited onto the hole transporting layer at a deposition rate of 0.1 nm/second, to form a luminous layer having a thickness of 15 nm and containing 90 vol % compound H-1 and 10 vol % exemplary compound 1-10.

(126) Compound HB-1 (illustrated below) was deposited onto the luminous layer at a deposition rate of 0.1 nm/second, to form an hole blocking layer having a thickness of 4.0 nm.

(127) Compound E-1 (illustrated below) was deposited onto the hole blocking layer at a deposition rate of 0.1 nm/second, to form an electron transporting layer having a thickness of 45 nm.

(128) A potassium fluoride layer having a thickness of 2.0 nm was then formed on the electron transporting layer, and aluminum was deposited onto the potassium fluoride layer, to form a cathode having a thickness of 100 nm.

(129) ##STR00062##

(130) The non-luminous surface of the element was covered with a cylindrical glass casing in an atmosphere of nitrogen gas having a purity of 99.999% or more, and lead wires for the electrodes were provided, to prepare an organic EL element.

(131) The resultant organic EL element was operated at room temperature (about 23 to 25 C.) and a constant current of 2.5 mA/cm.sup.2. The organic EL element emitted blue light.

INDUSTRIAL APPLICABILITY

(132) The present invention provides a method for synthesizing an organic metal complex having a substituent capable of coordinating to a central metal ion. A compound synthesized by the method of the present invention is particularly suitable for use in an organic electroluminescent element.