Method for producing multi-substituted biphenyl compound

Abstract

To provide a method for producing a poly-substituted biphenyl compound in high regioselectivity without requiring complicated catalyst preparation.SOLUTION: The method for producing a poly-substituted biphenyl compound represented by general formula (2) includes a step of oxidatively dimerizing an aromatic compound represented by general formula (1) in the presence of a platinum compound and a copper compound.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a polyvalently substituted biphenyl compound. [Background technology]

[0002] Polyvalently substituted biphenyl compounds are useful compounds used as active pharmaceutical ingredients, electronic information materials, and their synthetic intermediates. Among them, 3,3',4,4'-biphenyltetracarboxylate tetramethyl (hereinafter referred to as s-BPTT) is a particularly useful symmetrically substituted biphenyl compound, and various methods for producing it using catalytic systems have been proposed. For example, a method is known in which dimethyl phthalate is oxidatively dimerized in the presence of a palladium catalyst, a basic bidentate ligand, and oxygen (Patent Documents 1 and 2, and Non-Patent Document 1).

[0003] In the oxidative dimerization reaction of dimethyl phthalate, in addition to the symmetrical tetramethyl biphenyltetracarboxylate (s-BPTT), the asymmetrical tetramethyl 2,3,3',4'-biphenyltetracarboxylate (a-BPTT) can be produced as a positional isomer.

[0004] In the case of a palladium catalyst system, the regioselectivity of this reaction is controlled by the basic bidentate ligand, and it is known that s-BPTT is produced preferentially over a-BPTT in a ratio of 10:1 to 80:1. Also known is a method for producing s-BPTT using a catalyst in which palladium and a noble metal other than palladium are immobilized on a support, and it has been reported that s-BPTT is produced with a regioselectivity of 25:1 when palladium is combined with gold, and 28:1 when palladium is combined with platinum (Patent Document 3).

[0005] Known methods for producing s-BPTT using only precious metals other than palladium as catalysts include, for example, the oxidative dimerization of dimethyl phthalate using a gold or platinum catalyst immobilized on a support. It is known that s-BPTT is produced with a regioselectivity of up to 100:1 when a gold catalyst immobilized on a support is used, but the regioselectivity when a platinum catalyst immobilized on a support is used has not been disclosed (Patent Document 4 and Non-Patent Document 2). Furthermore, no methods for producing s-BPTT using platinum that is not immobilized on a support are known, and no examples have been reported of using a platinum compound directly as a catalyst or using a platinum compound in combination with a copper compound as a catalyst. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] European Patent Application Publication No. 0019483 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-100616 [Patent Document 3] JP 2016-037500 A [Patent Document 4] International Publication No. 2014 / 057992 [Non-patent literature]

[0007] [Non-Patent Document 1] Shiotani et al., Journal of Molecular Catalysis, 1986, Vol. 34, pp. 57-66. [Non-patent document 2] Ishida et al., ChemSusChem, 2015, Vol. 8, pp. 695-701. Summary of the Invention [Problem to be solved by the invention]

[0008] When the oxidative dimerization reaction of dimethyl phthalate was carried out in the presence of a palladium catalyst, 1,10-phenanthroline monohydrate, air, and copper acetate monohydrate with reference to Non-Patent Document 1, the regioselectivity for the production of s-BPTT was a low value of 6.3:1, indicating that there was a problem with the regioselectivity. Furthermore, the method of carrying out the oxidative dimerization reaction using a noble metal catalyst immobilized on a support requires a separate and complicated catalyst preparation, which poses a problem for use in industrial production.

[0009] Therefore, an object of the present invention is to provide a method for producing polyvalently substituted biphenyl compounds with high regioselectivity in the oxidative dimerization reaction of aromatic compounds having identical substituents at the ortho positions, such as dimethyl phthalate, without requiring complicated catalyst preparation. [Means for solving the problem]

[0010] As a result of intensive research to solve the above problems, the present inventors have found that by using a platinum compound and a copper compound in combination, an oxidative dimerization reaction of an aromatic compound having the same substituent at the ortho position proceeds, and a polyvalently substituted biphenyl compound can be produced with high regioselectivity, thereby completing the present invention. That is, the present invention includes the following. [1] A method for producing a polyvalent substituted biphenyl compound represented by the following general formula (2), comprising a step of oxidatively dimerizing an aromatic compound represented by the following general formula (1) in the presence of a platinum compound and a copper compound:

[0011] [ka]

[0012] [In the above general formulas (1) and (2), R 1 represents a hydroxy group, an alkoxy group, an amino group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aliphatic hydrocarbon group, or a group formed by combining these, and may have a salt structure. 1are identical, and R 1 is a carboxyl group, the carboxyl groups on adjacent carbons may be bonded to each other to form an anhydride. [2]R 1 is a carboxyl group or an esterified carboxyl group. [3] The method according to [1] or [2], wherein the platinum compound is an anhydride or hydrate of hexachloroplatinic acid (IV), sodium hexachloroplatinate (IV), or sodium tetrachloroplatinate (II). [4] The production method according to any one of [1] to [3], wherein a ligand compound is added in addition to the platinum compound and the copper compound in the step. [5] The method according to [4], wherein the ligand compound is a diol, a β-dicarbonyl compound, or a bidentate phosphoric acid oxide. [Effects of the Invention]

[0013] According to the present invention, a polysubstituted biphenyl compound can be produced with high regioselectivity by oxidatively dimerizing an aromatic compound having the same substituent at the ortho-position in the presence of a platinum compound and a copper compound. For example, s-BPTT can be produced regioselectively by oxidatively dimerizing dimethyl phthalate using the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below.

[0015] (aromatic compounds) The aromatic compound represented by the following general formula (1) used as a raw material in the present invention has the same substituent R 1 is a disubstituted benzene having the formula:

[0016] [ka]

[0017] R 1represents a hydroxy group, an alkoxy group, an amino group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aliphatic hydrocarbon group, or a group formed by combining these groups.

[0018] In the present invention, the term "a group formed by combining these (substituents)" means a group formed by substituting a hydrogen atom on a substituent with another substituent. 1 The "group formed by combining these" in the above means, for example, a group formed by substituting a hydrogen atom of at least one group selected from an alkoxy group, an amino group, an acyl group, an esterified carboxyl group, an amidated carboxyl group, and an aliphatic hydrocarbon group with at least one group selected from a hydroxy group, an alkoxy group, an amino group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, and an aliphatic hydrocarbon group. 1 The number of combinations of the substituents R is preferably 1 to 10, and more preferably 1 to 5. 1 The "group formed by combining these" in R is not limited to the following, but examples thereof include a dialkylamino group and a dialkylaminocarbonyl group. 1 is a carboxyl group, the carboxyl groups on adjacent carbons may be linked to each other to form an anhydride.

[0019] The alkoxy group and acyl group preferably have 1 to 10 carbon atoms, and more preferably have 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 20 carbon atoms, and more preferably has 2 to 10 carbon atoms.

[0020] The amidated carboxyl group preferably has 1 to 20 carbon atoms, and more preferably has 1 to 10 carbon atoms.

[0021] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0022] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, a halogen atom, a hydroxy group, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0023] The alkoxy group, acyl group and amidated carboxyl group which are substituents on the aliphatic hydrocarbon group preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms.

[0024] The aromatic compound represented by the general formula (1) includes R 1However, it is preferably a carboxyl group (carboxyl groups on adjacent carbon atoms may be bonded to each other to form an anhydride) or an esterified carboxyl group. Examples of the aromatic compound represented by the above general formula (1) include, but are not limited to, 1,2-dimethoxybenzene, N,N,N',N'-tetramethyl-1,2-benzenediamine, 1,2-diacetylbenzene, dimethyl phthalate, phthalic acid, phthalic anhydride, and orthoxylene.

[0025] The aromatic compound represented by the general formula (1) may be a salt. When the aromatic compound represented by the general formula (1) is a salt, the substituent R 1 has a salt structure. 1 Examples of the salt structure include an ammonium salt formed from an amino group and an inorganic acid, and a carboxylate structure formed from a carboxyl group and a metal. Examples of the salt of the aromatic compound represented by the general formula (1) include, but are not limited to, inorganic acid salts such as hydrochloride, bromate, iodate, perchlorate, carbonate, sulfate, trifluoromethanesulfonate, tetrafluoroborate, and hexafluorophosphate, and metal salts such as lithium salt, sodium salt, and potassium salt.

[0026] As the aromatic compound represented by the general formula (1), a phthalic acid diester represented by the following general formula (3) (R 1 is an esterified carboxyl group) is useful because it can produce biphenyltetracarboxylic acid tetraesters, which are used as raw materials for pharmaceutical ingredients and polyimide resins.

[0027] [ka]

[0028] In the above general formula (3), R 2 represents an aryl group or an aliphatic hydrocarbon group. The aryl group preferably has 6 to 19 carbon atoms, and more preferably has 6 to 10 carbon atoms.

[0029] The aryl group may have a substituent, and the above carbon number does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, hydroxy groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, arylalkyl groups, dialkylamino groups, and dialkylaminocarbonyl groups. The number of types of the combined substituents is preferably 1 to 10, and more preferably 1 to 5. The alkyl groups, alkoxy groups, acyl groups, and amidated carboxyl groups preferably have 1 to 10 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl groups, alkynyl groups, and esterified carboxyl groups preferably have 2 to 10 carbon atoms, and more preferably have 2 to 5 carbon atoms. The above cycloalkyl group and cycloalkenyl group preferably have 3 to 10 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0030] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0031] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, a hydroxy group, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0032] The alkoxy group, acyl group and amidated carboxyl group which are substituents on the aliphatic hydrocarbon group preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms.

[0033] Examples of the phthalic acid diester represented by the general formula (3) include, but are not limited to, diphenyl phthalate, dimethyl phthalate, diethyl phthalate, and dibutyl phthalate.

[0034] (Platinum compound) Examples of platinum compounds used in the present invention include platinum element or compounds containing platinum, including, but not limited to, platinum chloride (II), platinum chloride (IV), platinum bromide (II), platinum bromide (IV), platinum iodide (II), platinum iodide (IV), platinum hydroxide (II), platinum hydroxide (IV), platinum oxide (II), platinum oxide (IV), bis(acetylacetonato)platinum (II), tetraammineplatinum (II) chloride, tetraammineplatinum (II) nitrate, hexachloroplatinic (IV) acid, sodium hexachloroplatinate (IV), and sodium tetrachloroplatinate (II). Among these, hexachloroplatinic (IV) acid, sodium hexachloroplatinate (IV), and sodium tetrachloroplatinate (II) are more preferred. These platinum compounds may be anhydrous or hydrated.

[0035] The amount of the platinum compound used is 0.005 mol % or more, preferably 0.02 mol % or more, and 10 mol % or less, preferably 1.0 mol % or less, based on the aromatic compound represented by the general formula (1).

[0036] The platinum compound may be a commercially available product, may be synthesized by a known method or a method similar thereto, or may be prepared in a reaction system.

[0037] (copper compound) The copper compound used in the present invention is exemplified by elemental copper or a compound containing copper, and includes, but is not limited to, copper carboxylates and copper compounds other than copper carboxylates.

[0038] The amount of the copper compound used is 10 mol % or more, preferably 100 mol % or more, and 10,000 mol % or less, preferably 5,000 mol % or less, based on the platinum compound.

[0039] Examples of copper carboxylates include, but are not limited to, copper(II) acetate, copper(II) propionate, copper(II) 2-methylpropionate, copper(II) pivalate, copper(II) lactate, copper(II) butyrate, copper(II) benzoate, and copper(II) trifluoroacetate, with copper(II) acetate, copper(II) propionate, copper(II) pivalate, and copper(II) butyrate being more preferred. The copper carboxylates may be anhydrous or hydrated.

[0040] Examples of copper compounds other than copper carboxylates include, but are not limited to, copper chloride(I), copper chloride(II), copper bromide(I), copper bromide(II), copper iodide(I), copper iodide(II), copper nitrate(II), copper nitrite(II), copper sulfate(II), copper phosphate(II), copper oxide(I), copper oxide(II), copper hydroxide(II), bis(acetylacetonato)copper(II), bis(1,1,1,5,5,5-hexafluoroacetylacetonato)copper(II), copper trifluoromethanesulfonate, copper paratoluenesulfonate, and copper cyanide(I). Copper compounds other than copper carboxylates can be used in either anhydrous or hydrated form.

[0041] The copper compound may be a commercially available product, may be synthesized by a known method or a method similar thereto, or may be prepared in the reaction system.

[0042] (ligand compound) In the present invention, in order to enhance regioselectivity, it is preferable to carry out the reaction using a ligand compound capable of forming a complex with a platinum compound. When an aromatic compound represented by the above general formula (1) is oxidatively dimerized using a ligand compound capable of forming a complex with a platinum compound, the production of an asymmetrically substituted biphenyl compound (meaning a biphenyl compound having substituents at asymmetric positions on the two benzene rings) can be suppressed among the isomers of the resulting polyvalently substituted biphenyl compound, and a symmetrically substituted biphenyl compound (meaning a biphenyl compound having substituents at symmetric positions on the two benzene rings) can be selectively produced. For example, when the starting material is a phthalic acid diester, the production of the asymmetrically substituted product a-BPTT can be suppressed, and the symmetrically substituted product s-BPTT can be selectively produced.

[0043] When the reaction is carried out using a coordination compound, the amount of the coordination compound used is 10 mol % or more, preferably 50 mol % or more, and 500 mol % or less, preferably 250 mol % or less, based on the platinum compound.

[0044] The ligand compound used in the present invention, which can form a complex with a platinum compound, includes, but is not limited to, a basic ligand compound, an N-heterocyclic carbene, a phosphine, a diol, a β-dicarbonyl compound, or a phosphoric acid oxide, among which a diol, a β-dicarbonyl compound, or a bidentate phosphoric acid oxide is preferred. The amount of these preferred ligand compounds used is 10 mol % or more, preferably 50 mol % or more, and 500 mol % or less, preferably 250 mol % or less, based on the platinum compound.

[0045] <Basic Ligand Compounds> The basic ligand compound used as the ligand compound is preferably one having a pyrrole skeleton, imidazole skeleton, pyrazole skeleton, oxazole skeleton, isoxazole skeleton, thiazole skeleton, isothiazole skeleton, pyridine skeleton, pyrimidine skeleton, quinoline skeleton, or phenanthroline skeleton, among those capable of forming a complex with a platinum compound via a nitrogen atom. Examples of the basic ligand compound include, but are not limited to, pyridine, 1,10-phenanthroline, 2,2'-bipyridyl, ethylenediamine, 1,2-benzenediamine, terpyridine, and (R,R)-6,6'-bis(1-hydroxy-2,2'-dimethylpropyl)-2,2'-bipyridine (represented by the following general formula (4)).

[0046] [ka]

[0047] <N-heterocyclic carbene> The N-heterocyclic carbene used as the ligand compound is exemplified by a compound having a carbene structure in a cyclic skeleton consisting of nitrogen and carbon, and is preferably an imidazol-2-ylidene derivative or an imidazolidin-2-ylidene derivative. Examples of the imidazol-2-ylidene derivative or imidazolidin-2-ylidene derivative include, but are not limited to, 1,3-ditertiarybutylimidazol-2-ylidene, 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene, 1,3-dicyclohexylimidazol-2-ylidene, 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, and 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene.

[0048] The N-heterocyclic carbene may be prepared by reacting an appropriate base with an imidazolium salt or imidazolinium salt in a reaction system. Examples of the imidazolium salt or imidazolinium salt include, but are not limited to, 1,3-bis(2,6-diisopropylphenyl)imidazolium chloride, 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride, 1,3-dicyclohexylimidazolium chloride, 1,3-bis(2,6-diisopropylphenyl)imidazolinium chloride, and 1,3-bis(2,4,6-trimethylphenyl)imidazolinium chloride.

[0049] The base used in preparing the N-heterocyclic carbene in situ includes, but is not limited to, potassium carbonate, sodium carbonate, sodium hydroxide, potassium hydroxide, potassium tert-butoxide, sodium hydride, potassium hexamethyldisilazide, or lithium diisopropylamide.

[0050] Phosphine The phosphine used as the ligand compound may be either monodentate or bidentate. In the case of monodentate, trialkylphosphines, dialkylarylphosphines, alkyldiarylphosphines, or triarylphosphines are preferred, with trialkylphosphines or triarylphosphines being more preferred. In the case of bidentate, those having two phosphorus atoms on different carbon atoms are preferred, with those having phosphorus atoms bonded to at least two aryl groups on different carbon atoms being more preferred. Examples of the phosphines include, but are not limited to, tricyclohexylphosphine, triphenylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,1'-bis(diphenylphosphino)ferrocene, and 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl.

[0051] Diol The diol used as the ligand compound has two hydroxy groups on different carbon atoms, and a base may be added to deprotonate the hydroxy groups. The diol is not limited to the following, but is preferably one represented by the following general formulas (5) to (7).

[0052] [ka]

[0053] In the above general formula (5), R 3 ~R 6 are the same or different and represent a hydrogen atom, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aryl group, or an aliphatic hydrocarbon group. 3 ~R 6 may be the same or different and may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the combination of the above-mentioned substituents is preferably 1 to 10, and more preferably 1 to 5. In addition, the substituents on adjacent carbon atoms may be bonded to form a ring.

[0054] The alkoxy group, acyl group and amidated carboxyl group preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms.

[0055] The esterified carboxyl group preferably has 2 to 10 carbon atoms, and more preferably has 2 to 5 carbon atoms.

[0056] The aryl group preferably has 6 to 20 carbon atoms, and more preferably has 6 to 10 carbon atoms.

[0057] The aryl group may have a substituent, and the number of carbon atoms in the above-mentioned range does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned substituents combined is preferably 1 to 10, and more preferably 1 to 5.

[0058] The alkyl group, alkoxy group, acyl group and amidated carboxyl group, which are substituents on the aryl group, preferably have 1 to 10 carbon atoms; the alkenyl group, alkynyl group and esterified carboxyl group preferably have 2 to 10 carbon atoms; the cycloalkyl group and cycloalkenyl group preferably have 3 to 10 carbon atoms; and the aryl group preferably have 6 to 15 carbon atoms.

[0059] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0060] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the combined substituents is preferably 1 to 10, and more preferably 1 to 5. The aryl group, which is a substituent on the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms; the alkoxy group, acyl group, and amidated carboxyl group preferably has 1 to 10 carbon atoms; and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0061] In the above general formula (6), R 7 ~R 10 and R 7 '~R 10 R ' may be the same or different and represent a hydrogen atom, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aryl group, or an aliphatic hydrocarbon group. 7 ~R 10 and R 7 '~R 10 The R' may be the same or different and may be a substituent formed by combining two or more of the above-mentioned substituents, and are not limited to the following, but examples thereof include a dialkylamino group and a dialkylaminocarbonyl group. The number of types of the combination of the above-mentioned substituents is preferably 1 to 10, more preferably 1 to 5. In addition, the number of types of the substituents on the adjacent carbon atoms and R 10 and R 10 ' may be bonded to form a ring.

[0062] The alkoxy group, acyl group and amidated carboxyl group preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms.

[0063] The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 10. The aryl group may have a substituent, and the number of carbon atoms does not include the substituent.

[0064] Examples of the substituent on the aryl group include, but are not limited to, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, an aryl group, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, and a dialkylaminocarbonyl group.

[0065] The number of types of the combination of the above substituents is preferably 1 to 10, and more preferably 1 to 5.

[0066] The alkyl group, alkoxy group, acyl group and amidated carboxyl group, which are substituents on the aryl group, preferably have 1 to 10 carbon atoms; the alkenyl group, alkynyl group and esterified carboxyl group preferably have 2 to 10 carbon atoms; the cycloalkyl group and cycloalkenyl group preferably have 3 to 10 carbon atoms; and the aryl group preferably have 6 to 15 carbon atoms.

[0067] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0068] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0069] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0070] In the above general formula (7), R 11 , R 12 are the same or different and represent a hydrogen atom, an aryl group or an aliphatic hydrocarbon group; n represents an integer of 2 to 5.

[0071] The aryl group preferably has 6 to 20 carbon atoms, and more preferably has 6 to 10 carbon atoms.

[0072] The aryl group may have a substituent, and the number of carbon atoms in the above-mentioned range does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned substituents combined is preferably 1 to 10, and more preferably 1 to 5.

[0073] Preferably, the alkyl group, alkoxy group, acyl group and amidated carboxyl group have 1 to 10 carbon atoms, the alkenyl group, alkynyl group and esterified carboxyl group have 2 to 10 carbon atoms, the cycloalkyl group and cycloalkenyl group have 3 to 10 carbon atoms, and the aryl group have 6 to 15 carbon atoms.

[0074] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0075] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0076] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0077] Specific examples of diols include, but are not limited to, catechol and 1,1'-bi-2-naphthol, which have the following structures:

[0078] [ka]

[0079] Examples of bases used to deprotonate the hydroxy group of the diol include, but are not limited to, potassium carbonate, sodium carbonate, sodium hydroxide, potassium hydroxide, potassium tert-butoxide, sodium hydride, potassium hexamethyldisilazide, and lithium diisopropylamide.

[0080] β-Dicarbonyl Compounds Examples of the β-dicarbonyl compound used as the ligand compound include β-diketones, β-ketoesters, and malonic acid esters, which have at least one hydrogen atom at the α-position. The β-dicarbonyl compound forms a complex with the platinum compound by abstracting the hydrogen atom at the α-position with a base. The β-dicarbonyl compound is not limited to the following, but is preferably, for example, one represented by the following general formula (8):

[0081] [ka]

[0082] In the above general formula (8), R 13 , R 14 are the same or different and represent an alkoxy group, an aryloxy group, an aryl group, or an aliphatic hydrocarbon group; R 15 represents a hydrogen atom, an aryl group, or an aliphatic hydrocarbon group. The alkoxy group preferably has 1 to 10 carbon atoms, and more preferably has 1 to 5 carbon atoms. The aryloxy group and aryl group preferably have 6 to 20 carbon atoms, and more preferably has 6 to 10 carbon atoms.

[0083] The aryloxy group and the aryl group may have a substituent, and the above carbon number does not include the substituent. Examples of the substituent on the aryloxy group and the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryloxy group and the aryl group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned substituents combined is preferably 1 to 10, and more preferably 1 to 5.

[0084] Preferably, the alkyl group, alkoxy group, acyl group and amidated carboxyl group have 1 to 10 carbon atoms, the alkenyl group, alkynyl group and esterified carboxyl group have 2 to 10 carbon atoms, the cycloalkyl group and cycloalkenyl group have 3 to 10 carbon atoms, and the aryl group have 6 to 15 carbon atoms.

[0085] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups. The alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0086] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0087] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0088] Specific examples of the β-dicarbonyl compound include, but are not limited to, 1,3-diphenylpropane-1,3-dione, 1,3-bis(4-methoxyphenyl)propane-1,3-dione, 1,3-bis(4-nitrophenyl)propane-1,3-dione, and 1,3-bis(4-(trifluoromethyl)phenyl)propane-1,3-dione, each of which has the following structure:

[0089] [ka]

[0090] Examples of bases used to abstract the hydrogen atom at the α-position of a β-dicarbonyl compound include, but are not limited to, potassium carbonate, sodium carbonate, potassium tert-butoxide, sodium hydride, potassium hexamethyldisilazide, and lithium diisopropylamide.

[0091] <Phosphate oxide> The phosphoric acid oxide used as the ligand compound may be either monodentate or bidentate. In the case of monodentate, trialkylphosphine oxide, dialkylarylphosphine oxide, alkyldiarylphosphine oxide, or triarylphosphine oxide is preferred, with trialkylphosphine oxide and triarylphosphine oxide being more preferred. Examples of trialkylphosphine oxide and triarylphosphine oxide include, but are not limited to, tricyclohexylphosphine oxide and triphenylphosphine oxide. The bidentate phosphoric acid oxide is a compound having two phosphoric acid oxide moieties in the same molecule, and is preferably, but not limited to, those represented by the following general formulas (9) to (11).

[0092] [ka]

[0093] In the above general formula (9), R 16 ~R19 are the same or different and represent an aryl group or an aliphatic hydrocarbon group; R 20 , R 21 are the same or different and represent a hydrogen atom, an aryl group or an aliphatic hydrocarbon group, and m represents an integer of 2 to 5.

[0094] The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 10 carbon atoms. The aryl group may have a substituent, and the above number of carbon atoms does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, more preferably 1 to 5.

[0095] Preferably, the alkyl group, alkoxy group, acyl group and amidated carboxyl group have 1 to 10 carbon atoms, the alkenyl group, alkynyl group and esterified carboxyl group have 2 to 10 carbon atoms, the cycloalkyl group and cycloalkenyl group have 3 to 10 carbon atoms, and the aryl group have 6 to 15 carbon atoms.

[0096] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0097] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0098] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0099] In the above general formula (10), R 22 ~R 25 are the same or different and represent an aryl group or an aliphatic hydrocarbon group, and the aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 10 carbon atoms.

[0100] The aryl group may have a substituent, and the above carbon number does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned substituents combined is preferably 1 to 10, and more preferably 1 to 5.

[0101] The alkyl group, alkoxy group, acyl group, and amidated carboxyl group preferably have 1 to 10 carbon atoms, the alkenyl group, alkynyl group, and esterified carboxyl group preferably have 2 to 10 carbon atoms, the cycloalkyl group and cycloalkenyl group preferably have 3 to 10 carbon atoms, and the aryl group preferably have 6 to 15 carbon atoms. Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups. The alkyl group preferably has 1 to 15 carbon atoms, and more preferably has 1 to 5 carbon atoms. The alkenyl group and alkynyl group preferably have 2 to 15 carbon atoms, and more preferably has 2 to 5 carbon atoms. The cycloalkyl group and cycloalkenyl group preferably have 3 to 15 carbon atoms, and more preferably has 4 to 7 carbon atoms.

[0102] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0103] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0104] In the above general formula (11), R 26 ~R 29 are the same or different and represent an aryl group or an aliphatic hydrocarbon group; R 30 ~R 33 and R 30 '~R 33 R ' may be the same or different and represent a hydrogen atom, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aryl group, or an aliphatic hydrocarbon group. 30 ~R 33 and R 30 '~R 33 The R' may be the same or different and may be a substituent formed by combining two or more of the above-mentioned substituents, and are not limited to the following, but examples thereof include a dialkylamino group and a dialkylaminocarbonyl group. The number of types of the combination of the above-mentioned substituents is preferably 1 to 10, more preferably 1 to 5. In addition, the number of types of the substituents on the adjacent carbon atoms and R 33 and R 33 may be bonded to form a ring.

[0105] The alkoxy group, acyl group and amidated carboxyl group preferably have 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms.

[0106] The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 10 carbon atoms. The aryl group may have a substituent, and the above number of carbon atoms does not include the substituent. Examples of the substituent on the aryl group include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, alkynyl groups, aryl groups, alkoxy groups, amino groups, nitro groups, cyano groups, acyl groups, carboxyl groups, esterified carboxyl groups, and amidated carboxyl groups. Furthermore, the substituent on the aryl group may be a substituent formed by combining two or more of the above-mentioned substituents, and examples thereof include, but are not limited to, an arylalkyl group, a dialkylamino group, or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, more preferably 1 to 5.

[0107] The alkyl group, alkoxy group, acyl group and amidated carboxyl group, which are substituents of the aryl group, preferably have 1 to 10 carbon atoms; the alkenyl group, alkynyl group and esterified carboxyl group preferably have 2 to 10 carbon atoms; the cycloalkyl group and cycloalkenyl group preferably have 3 to 10 carbon atoms; and the aryl group preferably have 6 to 15 carbon atoms.

[0108] Examples of aliphatic hydrocarbon groups include, but are not limited to, alkyl groups, cycloalkyl groups, alkenyl groups, cycloalkenyl groups, and alkynyl groups, and the alkyl groups preferably have 1 to 15 carbon atoms, and more preferably have 1 to 5 carbon atoms. The alkenyl and alkynyl groups preferably have 2 to 15 carbon atoms, and more preferably have 2 to 5 carbon atoms. The cycloalkyl and cycloalkenyl groups preferably have 3 to 15 carbon atoms, and more preferably have 4 to 7 carbon atoms.

[0109] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, an aryl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the above-mentioned combined substituents is preferably 1 to 10, and more preferably 1 to 5.

[0110] The aryl group, which is a substituent of the aliphatic hydrocarbon group, preferably has 6 to 10 carbon atoms, the alkoxy group, acyl group and amidated carboxyl group preferably has 1 to 10 carbon atoms, and the esterified carboxyl group preferably has 2 to 10 carbon atoms.

[0111] Specific examples of bidentate phosphate oxides include, but are not limited to, 1,2-bis(diphenylphosphino)ethane dioxide, 1,3-bis(diphenylphosphino)propane dioxide, 1,1′-bis(diphenylphosphino)ferrocenedioxide, and 2,2′-bis(diphenylphosphinyl)-1,1′-binaphthyl.

[0112] Note that 1,2-bis(diphenylphosphino)ethane dioxide, 1,3-bis(diphenylphosphino)propane dioxide, 1,1′-bis(diphenylphosphino)ferrocenedioxide, and 2,2′-bis(diphenylphosphinyl)-1,1′-binaphthyl each have the following structure.

[0113] [ka]

[0114] (Reaction conditions for the production method) In the present invention, the aromatic compound represented by the general formula (1) is subjected to an oxidative dimerization reaction at a reaction temperature of 50°C or higher, preferably 100°C or higher, more preferably 140°C or higher, and 300°C or lower, preferably 250°C or lower.

[0115] In the present invention, the reaction time can be set appropriately and is typically 30 minutes or more, for example, 30 minutes to 24 hours.

[0116] This reaction may be carried out in the presence of a solvent, which may include, but is not limited to, dichloromethane, chloroform, dichloroethane, hexane, heptane, octane, cyclohexane, methyl tert-butyl ether, cyclopentyl methyl ether, diethyl ether, dimethoxyethane, tetrahydrofuran (hereinafter referred to as THF), 1,4-dioxane, methanol, ethanol, 1-propanol, 2-propanol, methyl ethyl ketone, methyl isobutyl ketone, acetone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, octyl acetate, ethyl propionate, propyl propionate, butyl propionate, octyl propionate, ethylene glycol diacetate, dimethyl adipate, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropylene urea, acetonitrile, propionitrile, dimethyl sulfoxide, sulfolane, or water.

[0117] The solvent used in this reaction may be one type or a combination of two or more types. When two or more types of solvents are used in combination, they may be either immiscible and heterogeneous, or mixed and homogeneous.

[0118] The amount of the solvent used in this reaction can be appropriately determined, and is preferably 0.1 to 100 times by volume relative to the aromatic compound represented by the general formula (1).

[0119] To increase the yield, this reaction may be carried out in an atmosphere of an oxygen-containing gas. The oxygen-containing gas may be pure oxygen gas, but considering the risk of explosion, it is preferably air or an oxygen-containing mixed gas diluted with an inert gas such as nitrogen gas or carbon dioxide gas to an oxygen content of 5 to 50% by volume. The oxygen partial pressure is 0.01 atmospheres or more, preferably 0.05 atmospheres or more, and 200 atmospheres or less, preferably 50 atmospheres or less.

[0120] (Ingredients used in the manufacturing process) In the past, carboxylic acids have been used to promote the oxidative coupling reaction of aromatic compounds using metal catalysts. In the present invention, a carboxylic acid represented by the following general formula (12) may be added to promote the reaction, and the amount used is preferably 0.01 volume times or more, more preferably 0.1 volume times or more, relative to the aromatic compound represented by the general formula (1). Furthermore, the amount of the carboxylic acid used is preferably 100 volume times or less, more preferably 10 volume times or less, relative to the aromatic compound represented by the general formula (1).

[0121] [ka]

[0122] R 34represents a hydrogen atom or an aliphatic hydrocarbon group. Examples of the aliphatic hydrocarbon group include, but are not limited to, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, or an alkynyl group. The alkyl group preferably has 1 to 10 carbon atoms, and more preferably has 1 to 5 carbon atoms. The alkenyl group and alkynyl group preferably have 2 to 10 carbon atoms, and more preferably has 2 to 5 carbon atoms. The cycloalkyl group and cycloalkenyl group preferably have 3 to 15 carbon atoms, and more preferably has 4 to 7 carbon atoms.

[0123] The aliphatic hydrocarbon group may have a substituent, and the number of carbon atoms in the above figures does not include the substituent. Examples of the substituent on the aliphatic hydrocarbon group include, but are not limited to, a halogen atom, an alkoxy group, an amino group, a nitro group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, and an amidated carboxyl group. Furthermore, the substituent on the aliphatic hydrocarbon group may be a substituent formed by combining two or more of the above substituents, and examples thereof include, but are not limited to, a dialkylamino group or a dialkylaminocarbonyl group. The number of types of the combined substituents is preferably 1 to 10, and more preferably 1 to 5. The alkoxy group, acyl group, and amidated carboxyl group preferably have 1 to 10 carbon atoms, and more preferably have 1 to 5 carbon atoms. The esterified carboxyl group preferably has 2 to 10 carbon atoms, and more preferably has 2 to 5 carbon atoms.

[0124] The carboxylic acid represented by the above general formula (12) includes, but is not limited to, formic acid, acetic acid, propionic acid, pivalic acid, butyric acid, and trifluoroacetic acid.

[0125] (Polysubstituted biphenyl compounds) The product obtained by the method of the present invention is a polyvalent substituted biphenyl compound represented by the following general formula (2).

[0126] [ka] (In the above general formula (2), R 1 is R in the above general formula (1) 1 is synonymous with all R 1 are identical.)

[0127] That is, when the aromatic compound represented by the above general formula (1) is ortho-xylene, 3,3',4,4'-tetramethylbiphenyl is obtained; when it is 1,2-dimethoxybenzene, 3,3',4,4'-tetramethoxybiphenyl is obtained; and when it is dimethyl phthalate, BPTT is obtained. [Example]

[0128] The present invention will be described in more detail below using examples, although the technical scope of the present invention is not limited to these examples.

[0129] Unless otherwise specified, the identification of reaction products and measurement of the amount produced were carried out by comparing the retention time and peak intensity of the reaction products with those of standard substances using gas chromatography (FID detector). The measurement conditions were as follows: Equipment: Shimadzu GC-2010 Column: Shimadzu SH-I-1MS (inner diameter: 0.25 mm, length: 60 m, film thickness: 0.25 μm) Carrier gas: Helium 157.5kPa Temperature increase conditions: the temperature was increased from 60°C to 300°C at a rate of 15°C / min, and held at 300°C for 24 minutes.

[0130] In the examples, BPTT was obtained as a product of the oxidative dimerization reaction using dimethyl phthalate as a raw material, including the isomers s-BPTT and a-BPTT. The yield of s-BPTT, the reaction product, and the ratio of the amounts of s-BPTT and a-BPTT (hereinafter referred to as S / A), which are isomers of BPTT produced, were calculated according to the following formula and are shown in Table 1. The units in the calculation formula are moles.

[0131]

number

[0132] Comparative Example 1 In air, 1.18 g (6.08 mmol) of dimethyl phthalate, 14.0 mg (0.0624 mmol) of palladium(II) acetate, 122 mg (0.611 mmol) of copper(II) acetate monohydrate, and 12.0 mg (0.0605 mmol) of 1,10-phenanthroline monohydrate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0133] Example 1 In air, 1.25 g (6.44 mmol) of dimethyl phthalate, 33.4 mg (0.0594 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 119 mg (0.596 mmol) of copper(II) acetate monohydrate were weighed into a 10 mL two-neck flask, and the atmosphere was replaced with argon and stirred at 190°C for 2 hours. After the reaction, the flask was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0134] Example 2 In air, 1.21 g (6.23 mmol) of dimethyl phthalate, 36.3 mg (0.0646 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 120 mg (0.600 mmol) of copper(II) acetate monohydrate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0135] Example 3 In air, 1.19 g (6.13 mmol) of dimethyl phthalate, 33.5 mg (0.0596 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 371 mg (1.86 mmol) of copper(II) acetate monohydrate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0136] Example 4 In air, 1.21 g (6.23 mmol) of dimethyl phthalate, 31.8 mg (0.0566 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 126 mg (0.631 mmol) of copper(II) acetate monohydrate, 7.40 mg (0.0672 mmol) of catechol, and 23.0 mg (0.166 mmol) of potassium carbonate were weighed into a 45 mL stainless steel autoclave and stirred at 190 °C for 2 hours in a ChemStation. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0137] Example 5 In air, 1.21 g (6.23 mmol) of dimethyl phthalate, 36.2 mg (0.0644 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 120 mg (0.600 mmol) of copper(II) acetate monohydrate, 18.1 mg (0.0632 mmol) of 1,1'-bi-2-naphthol, and 21.8 mg (0.158 mmol) of potassium carbonate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0138] Example 6 In air, 1.18 g (6.08 mmol) of dimethyl phthalate, 30.8 mg (0.0548 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 116 mg (0.581 mmol) of copper(II) acetate monohydrate, 18.6 mg (0.0654 mmol) of 1,3-bis(4-methoxyphenyl)propane-1,3-dione, and 12.2 mg (0.0883 mmol) of potassium carbonate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0139] Example 7 In air, 1.16 g (5.97 mmol) of dimethyl phthalate, 31.5 mg (0.0561 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 115 mg (0.577 mmol) of copper(II) acetate monohydrate, 23.3 mg (0.0647 mmol) of 1,3-bis(4-(trifluoromethyl)phenyl)propane-1,3-dione, and 9.00 mg (0.0651 mmol) of potassium carbonate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0140] Example 8 In air, 1.20 g (6.18 mmol) of dimethyl phthalate, 33.5 mg (0.0596 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 126 mg (0.631 mmol) of copper(II) acetate monohydrate, and 35.9 mg (0.0612 mmol) of 1,1'-bis(diphenylphosphino)ferrocenedioxide were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0141] Example 9 In air, 1.20 g (6.18 mmol) of dimethyl phthalate, 33.2 mg (0.0591 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 120 mg (0.600 mmol) of copper(II) acetate monohydrate, and 41.2 mg (0.0629 mmol) of 2,2'-bis(diphenylphosphinyl)-1,1'-binaphthyl were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0142] Example 10 In air, 1.18 g (6.08 mmol) of dimethyl phthalate, 35.4 mg (0.0630 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 122 mg (0.611 mmol) of copper(II) acetate monohydrate, and 0.1 mL of acetic acid were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0143] Example 11 In air, 1.22 g (6.28 mmol) of dimethyl phthalate, 35.9 mg (0.0639 mmol) of sodium hexachloroplatinate(IV) hexahydrate, 363 mg (1.82 mmol) of copper(II) acetate monohydrate, and 0.1 mL of acetic acid were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0144] Example 12 In air, 1.19 g (6.13 mmol) of dimethyl phthalate, 38.2 mg (0.0680 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 135 mg (0.644 mmol) of copper(II) propionate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0145] Example 13 In air, 1.22 g (6.28 mmol) of dimethyl phthalate, 35.0 mg (0.0623 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 159 mg (0.598 mmol) of copper(II) pivalate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0146] Example 14 In air, 1.20 g (6.18 mmol) of dimethyl phthalate, 31.2 mg (0.0555 mmol) of sodium hexachloroplatinate(IV) hexahydrate, and 141 mg (0.593 mmol) of copper(II) butyrate were weighed into a 45 mL stainless steel autoclave and stirred at 190°C for 2 hours. After the reaction, the autoclave was air-cooled, and the reaction mixture was filtered through Celite with ethyl acetate. The filtrate was quantitatively analyzed by gas chromatography. The results are shown in Table 1.

[0147] [Table 1]

[0148] As can be seen from Examples 1 and 2 in Table 1, the use of oxygen-containing air improved the yield of s-BPTT, the oxidative dimerization reaction product. Furthermore, as can be seen from a comparison between Comparative Example 1 and Examples 1 to 14, the use of a platinum catalyst instead of a palladium catalyst improved the S / A ratio. That is, the regioselectivity of s-BPTT production improved. Furthermore, increasing the equivalent weight of copper(II) acetate monohydrate, as in Example 3, further improved the yield and regioselectivity compared to Example 2. When a diol, a β-dicarbonyl compound, or a bidentate phosphate oxide was used as a ligand (Examples 4 to 9), the yield decreased compared to when these compounds were not used (Example 2), but the S / A ratio improved to 20 or more. Furthermore, when 0.1 mL of acetic acid (0.1 volume times the volume of dimethyl phthalate) was added, as in Example 10, the regioselectivity decreased compared to when acetic acid was not added (Example 2), but the yield improved to 5% or more. Furthermore, by adding 0.1 mL of acetic acid (0.1 volume times the volume of dimethyl phthalate) and increasing the equivalent of copper(II) acetate monohydrate to 30 mol%, the yield and regioselectivity were improved compared to Example 2 (Example 11). Furthermore, when copper(II) propionate, copper(II) pivalate, or copper(II) butyrate was used as a copper carboxylate other than copper(II) acetate monohydrate, the reaction also proceeded without any problems (Examples 12 to 14). In particular, when copper(II) propionate was used, higher reactivity and selectivity were observed compared to Example 2. [Industrial Applicability]

[0149] According to the present invention, polyvalently substituted biphenyl compounds can be produced with high regioselectivity without the need for complicated catalyst preparation by oxidative dimerization of aromatic compounds having identical substituents at the ortho-positions, such as dimethyl phthalate, in the presence of a platinum compound and a copper compound.

Claims

1. A method for producing a polyvalent substituted biphenyl compound represented by the following general formula (2), comprising a step of oxidatively dimerizing an aromatic compound represented by the following general formula (1) in the presence of a platinum compound and a copper compound: 【Chemistry 1】 [In the above general formulas (1) and (2), R １ represents a hydroxy group, an alkoxy group, an amino group, a cyano group, an acyl group, a carboxyl group, an esterified carboxyl group, an amidated carboxyl group, an aliphatic hydrocarbon group, or a group formed by combining these, and may have a salt structure. １ are identical, and R １ is a carboxyl group, the carboxyl groups on adjacent carbons may be bonded to each other to form an anhydride.

2. R １ The method according to claim 1 , wherein is a carboxyl group or an esterified carboxyl group.

3. 3. The method according to claim 1, wherein the platinum compound is an anhydride or hydrate of hexachloroplatinic (IV) acid, sodium hexachloroplatinate (IV), or sodium tetrachloroplatinate (II).

4. 3. The method according to claim 1, wherein a ligand compound is added in addition to the platinum compound and copper compound in the step.

5. The method according to claim 4, wherein the ligand compound is a diol, a β-dicarbonyl compound, or a bidentate phosphoric acid oxide.

Images