JP2005145962A - Method for producing biphenyl and catalyst therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple and new method for preferably stereoselectively producing biphenyl by reacting an aromatic compound having a substituent or substituents to oxidatively dimerize. <P>SOLUTION: The biphenyl is produced by reacting the aromatic compound having a substituent or substituents to oxidatively dimerize by using a catalyst containing a rhodium compound, preferably the rhodium compound and a copper compound in an atmosphere containing molecular oxygen. Especially 2,3,3',4'-biphenyltetracarboxylic acid tetraester is stereoselectively produced from a phthalic acid diester. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a production method for producing biphenyls (biphenyl compounds) by subjecting an aromatic compound, particularly an aromatic compound having a substituent, to an oxidation dimerization reaction using a catalyst containing a rhodium compound in an atmosphere where molecular oxygen exists. About. In particular, the present invention relates to a production method for producing 2,3,3 ', 4'-biphenyltetracarboxylic acid tetraester using phthalic acid diester as an aromatic compound having a substituent.

  The method of producing bimolecular compounds of one molecule by cutting their carbon-hydrogen bonds from bimolecular aromatic compounds to form new carbon-carbon bonds is an industrially useful method of producing biphenyls. . As a catalyst used for such a reaction, a catalyst containing a palladium compound or a rhodium compound is known.

  Specifically, as a method for producing biphenyltetracarboxylic acid tetraester, biphenyltetracarboxylic acid tetraester is produced by an oxidation dimerization reaction of phthalic acid diester using a catalyst containing a palladium compound in an atmosphere where molecular oxygen exists. The method is known. In this production method, dimer 3,3 ′, 4,4′-biphenyltetracarboxylic acid tetraester (hereinafter sometimes abbreviated as s-BPTT) and 2,3,3 ′, 4 ′. A mixture of biphenyltetracarboxylic acid tetraester (hereinafter sometimes abbreviated as a-BPTT) can be obtained catalytically with respect to the palladium compound. There have been reported attempts to control the production ratio of these positional isomers, s-BPTT and a-BPTT.

  Patent Document 1 discloses a method for producing biphenyls by causing an organic palladium salt and an organic copper salt to exist in a reaction solution and oxidatively coupling a benzene-based aromatic compound in an atmosphere in which molecular oxygen exists. Has been described.

  In Patent Document 2, a phthalate ester is continuously or intermittently replenished with β-diketone at a high temperature in an atmosphere where molecular oxygen is present in the presence of a palladium salt and a copper salt. A method for producing oxidatively coupled biphenyl tetracarboxylic acid ester is disclosed.

  Patent Document 3 discloses a bidentate ligand compound in which a benzene-based aromatic compound is formed into a complex with a palladium salt, a copper salt, and a nitrogen atom and an oxygen atom in the molecule. And a method for producing biphenyls by oxidative coupling in the presence of molecular oxygen in an atmosphere.

On the other hand, Non-Patent Document 1 describes a method for producing biphenyls in which benzene or toluene is dimerized using RhCl (CO) (PMe ₃ ) ₂ as a catalyst in a nitrogen atmosphere in the presence of light. However, this method is not an oxidation dimerization reaction, but a dimerization reaction based on a dehydrogenation reaction by the catalytic action of a light-irradiated rhodium compound, which requires a complicated operation of light irradiation and low regioselectivity. Met. In other words, Non-Patent Document 1 discloses that an oxidation dimerization reaction is performed using a catalyst containing a rhodium compound in an atmosphere in which molecular oxygen is present, and in particular, phthalic diester is oxidized to a diphenyltetracarboxylic acid tetramer. The regioselective preparation of esters has not been described.

  Patent Document 4 describes a method for oxidative coupling of an olefin compound and an aromatic compound using a rhodium compound as a catalyst, but does not describe an oxidative coupling reaction between aromatic compounds. It was.

JP 55-141417 A JP 61-106541 A JP 2003-113143 A JP 2000-302700 A Chemistry Letters 1987, 2211-2214

  An object of the present invention is to provide a simple and novel production method for producing biphenyls preferably by regioselectively reacting an aromatic compound having a substituent with an oxidative dimerization reaction.

The present invention has been accomplished by finding a catalyst containing a rhodium compound as a novel catalyst of an oxidation dimerization reaction in which an aromatic compound having a substituent is oxidized and dimerized as a result of intensive studies by the inventors.
In the present invention, 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester is selectively obtained by subjecting phthalic diester to an oxidation dimerization reaction using a catalyst containing a rhodium compound in an atmosphere containing molecular oxygen. The catalyst containing a rhodium compound further contains a rhodium compound and a copper compound, and the catalyst containing the rhodium compound comprises a rhodium compound, a copper compound and a β-diketone. Concerning inclusion.

  Furthermore, this invention relates to the said rhodium compound being a compound shown by following Chemical formula (1).

（式中、Ｒ^１、Ｒ^２はアルキル基又はアリール基を示し、前記アルキル基又はアリール基は置換基を有してもよい。ＸはＦ、Ｃｌ、Ｂｒ又はＩのいずれかの原子を示し、ｎは１、２又は３のいずれかの整数を示す。）

(Wherein R ¹ and R ² represent an alkyl group or an aryl group, and the alkyl group or aryl group may have a substituent. X represents any atom of F, Cl, Br, or I) , N represents an integer of 1, 2 or 3.)

  The present invention also relates to a method for producing biphenyls, characterized by subjecting an aromatic compound having a substituent to an oxidative dimerization reaction using a catalyst containing a rhodium compound in an atmosphere containing molecular oxygen. It relates to the compound being a compound represented by the chemical formula (1).

  The present invention also relates to a catalyst for an oxidation dimerization reaction of an aromatic compound, which contains a rhodium compound represented by the chemical formula (1).

  The present invention provides a simple and novel production method for producing biphenyls preferably by regioselectively reacting an aromatic compound, particularly an aromatic compound having a substituent, by an oxidative dimerization reaction. In addition, when this reaction is used, a-BPTT can be obtained with a small amount of by-product of s-BPTT as compared with the conventional method, so that separation and purification of a-BPTT becomes extremely easy.

The present invention is a method for producing biphenyls (biphenyl compounds), characterized in that an aromatic compound having a substituent is subjected to an oxidative dimerization reaction using a catalyst containing a rhodium compound in an atmosphere containing molecular oxygen. .
In the present invention, the raw material is an aromatic compound, particularly an aromatic compound having a substituent, and preferably a compound represented by the following chemical formula (2).

（式中、Ｒは置換基であり、ｍは１〜４好ましくは１〜３特に１〜２のいずれかの整数である。）
前記化学式（２）のＲで示された置換基としては、炭素数１〜５のアルキル基、炭素数１〜５のアルコキシ基、炭素数１〜５のアルコキシカルボニル基、アリールオキシカルボキシ基、炭素数１〜５のアルカノイルオキシ基、炭素数１〜５のアルキル基の水素がアセチル基又はハロゲン基で置換されたアルキル基、ニトロ基及びハロゲン基などを挙げることができる。
化学式（２）で示される化合物の中でもフタル酸ジエステルは得られるビフェニルテトラカルボン酸テトラエステルがポリイミド樹脂の原料となるから特に有用である。尚、フタル酸ジエステルはその酸、酸無水物又は酸ハロゲン化物と末端に水酸基を有する化合物、例えば低級脂肪族アルコールや芳香族アルコールなどとの反応で容易に得ることができる。

(In the formula, R is a substituent, and m is an integer of 1 to 4, preferably 1 to 3, particularly 1 to 2.)
Examples of the substituent represented by R in the chemical formula (2) include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkoxycarbonyl group having 1 to 5 carbon atoms, an aryloxycarboxy group, and carbon. Examples thereof include an alkanoyloxy group having 1 to 5 carbon atoms, an alkyl group in which hydrogen of an alkyl group having 1 to 5 carbon atoms is substituted with an acetyl group or a halogen group, a nitro group, and a halogen group.
Among the compounds represented by the chemical formula (2), the phthalic acid diester is particularly useful because the obtained biphenyltetracarboxylic acid tetraester is a raw material for the polyimide resin. The phthalic acid diester can be easily obtained by reacting the acid, acid anhydride or acid halide with a compound having a hydroxyl group at the terminal, such as a lower aliphatic alcohol or aromatic alcohol.

  Specific compounds represented by the chemical formula (2) include, for example, toluene, ethylbenzene, orthoxylene, metaxylene, paraxylene, anisole, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, methyl toluate, Acetylbenzene, 2,6-dimethylbenzyl acetate, xylidene benzyl acetate, nitrobenzene, orthomethyl chlorobenzane, chlorobenzene, fluorinated benzene, orthochlorobenzene, trifluorotoluene, dimethyl terephthalate, diethyl terephthalate, dipropyl terephthalate, terephthalate Dibutyl acid, dimethyl isophthalate, diethyl isophthalate, dipropyl isophthalate, dibutyl isophthalate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, phthalate Dibutyl, dioctyl phthalate, can be cited such as suitably diphenyl phthalate.

  In the present invention, the catalyst containing a rhodium compound is preferably a catalyst comprising a rhodium compound, a catalyst comprising a combination of a rhodium compound and a copper compound, a catalyst comprising a combination of a rhodium compound and a β-diketone, or a rhodium compound. It is a catalyst comprising a combination of a copper compound and a β-diketone.

  Examples of rhodium compounds used in the present invention include rhodium chloride, rhodium bromide, rhodium iodide, di-μ-chlorotetra (carbonyl) dirhodium, di-μ-chlorotetra (ethylene) dirhodium, di-μ. -Rhodium halides such as chlorotetra (cyclooctene) dirhodium, di-μ-chlorobis (1,5-cyclooctadiene) dirhodium, dodecacarbonyl tetrarhodium, hexacarbonyl hexarhodium, hydridotetracarbonyl rhodium, acetylacetyl Examples thereof include carbonylated rhodiums such as natobis (carbonyl) rhodium, rhodium carboxylates such as rhodium acetate and rhodium trifluoroacetate, and anhydrides and hydrates such as acetylacetonatobis (ethylene) rhodium.

  Moreover, since the rhodium compound used in the present invention has high catalytic activity, a compound represented by the following chemical formula (1) and a hydrated product thereof are particularly suitable.

（式中、Ｒ^１、Ｒ^２はアルキル基又はアリール基を示し、前記アルキル基又はアリール基は置換基を有してもよい。ＸはＦ、Ｃｌ、Ｂｒ又はＩのいずれかの原子を示し、ｎは１、２又は３のいずれかの整数を示す。）

(Wherein R ¹ and R ² represent an alkyl group or an aryl group, and the alkyl group or aryl group may have a substituent. X represents any atom of F, Cl, Br, or I) , N represents an integer of 1, 2 or 3.)

  Specific examples of the rhodium compound represented by the chemical formula (1) include tris (acetylacetonato) rhodium, chlorobis (acetylacetonato) rhodium, tri (1,1,1,5,5,5-hexafluoro-acetyl. Preferred examples include anhydrides and hydrates such as acetonato) rhodium, tris (1,3-diphenyl-1,3-propanedionate) rhodium, and chlorobis (acetylacetonato) rhodium.

  The rhodium compound represented by the chemical formula (1) particularly useful as a catalyst for the oxidation dimerization reaction of the present invention is prepared from the trivalent rhodium halide described in Patent Document 4, the corresponding dicarbonyl compound and a base. Or a method by reaction with an enolate compound, or Am. Chem. Soc. 1953, 75, 984-985 can be suitably produced by a method in which rhodium nitrate is converted into rhodium hydroxide using a raw material and then reacted with acetylacetone.

  In the present invention, the rhodium compound represented by the chemical formula (1) may be prepared and used in advance by the above-described method or the like, or may be used so as to be generated in the reaction mixture of the oxidation dimerization reaction. I do not care. Specifically, the rhodium compound and the ligand may be separately added to the reaction mixture of the oxidation dimerization reaction so that the rhodium compound represented by the chemical formula (1) is generated in the reaction mixture. I do not care.

  In the present invention, the rhodium compound is used in an amount of 0.00001 times mol or more, particularly 0.00005 times mol or more, and 0.05 times mol or less based on the aromatic compound having a substituent of the raw material, for example, phthalic acid diester. In particular, the amount used is 0.01 times mol or less. The reaction proceeds even if the rhodium compound is less than 0.00001 times mol, but the reaction time becomes longer. Moreover, although it may be used in excess of 0.05 times mol, it is economically disadvantageous in terms of catalyst cost.

  In the present invention, it is preferable to use a catalyst in which a copper compound is combined with a rhodium compound because the reaction may be accelerated. Copper compounds include copper acetate, copper propionate, normal butyric acid copper, copper 2-methylpropionate, copper pivalate, copper lactate, copper butyrate, copper benzoate, copper trifluoroacetate, bis (acetylacetonato) copper , Bis (1,1,1-5,5,5-hexafluoroacetylacetonato) copper, copper chloride, copper bromide, copper iodide, copper nitrate, copper nitrite, copper sulfate, copper phosphate, copper oxide , Copper hydroxide, copper trifluoromethanesulfonate, copper paratoluenesulfonate, copper cyanide, and other anhydrides and hydrates. In particular, copper acetate, copper propionate, normal butyric acid copper, bis (acetylacetonato) copper, copper pivalate anhydride and hydrate are particularly preferred because of their high effect of promoting the reaction.

Furthermore, as a copper compound combined with a rhodium compound, since it has high catalytic activity, the copper compound which the hetero atom containing carbene compound couple | bonded with copper can be mentioned. Specific examples of the copper compound in which the heteroatom-containing carbene compound is bonded to copper include [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper (I) chloride, [1,3-bis (2, 4,6-trimethylphenyl) imidazolium] copper (I) chloride, [1.3-di-1-adamantyl-imidazolium] copper (I) chloride, and the like.
The copper compound in which the heteroatom-containing carbene compound is bonded to copper may be prepared in advance as a catalyst, and the heteroatom-containing carbene compound may be added to the reaction mixture of the oxidative dimerization reaction in the reaction mixture. You may use so that the copper compound which the hetero atom containing carbene compound couple | bonded with copper may produce | generate.

  The amount of copper compound used is 0.01-100 equivalents, preferably 0.1-100 equivalents, relative to the rhodium compound. Although it may be used in excess of 100 equivalents, it is economically disadvantageous in terms of catalyst cost.

  In the present invention, it is preferable to use a catalyst in which a rhodium compound is combined with a β-diketone, or a catalyst in which a rhodium compound and a copper compound are combined with a β-diketone, since the deactivation of the catalyst may be suppressed. β-diketone is a bidentate ligand that can be coordinated to a rhodium compound in a bidentate, and a compound represented by the following chemical formula (3) can be preferably used.

（式中Ｒ^３、Ｒ^５は独立にアルキル基好ましくは炭素数が１〜５のアルキル基又はアリール基を示し、前記アルキル基又はアリール基は置換基を有してもよい。Ｒ^４は水素、アルキル基好ましくは炭素数が１〜５のアルキル基又はアリール基を示し、前記アルキル基又はアリール基は置換基を有してもよい。）
前記β−ジケトンの具体例としては、アセチルアセトン、１，１，１，５，５，５−ヘキサフルオロ−アセチルアセトン、１，３−ジフェニル−１，３−プロパンジオンなどが挙げられる。

(Wherein R ³ and R ⁵ independently represent an alkyl group, preferably an alkyl group having 1 to 5 carbon atoms or an aryl group, and the alkyl group or aryl group may have a substituent. R ⁴ represents hydrogen. An alkyl group, preferably an alkyl group having 1 to 5 carbon atoms or an aryl group, and the alkyl group or aryl group may have a substituent.
Specific examples of the β-diketone include acetylacetone, 1,1,1,5,5,5-hexafluoro-acetylacetone, 1,3-diphenyl-1,3-propanedione, and the like.

  In the present invention, the β-diketone is preferably used in an amount of 0.01 to 50 equivalents, particularly 0.01 to 10 equivalents, relative to the rhodium compound. Although it may be used in excess of 50 equivalents, an excessive amount of β-diketone is not preferred because it may inhibit the reaction.

  The method for producing biphenyls of the present invention can be suitably reacted without a solvent, but a solvent may be used. Specific examples of the solvent to be used include carboxylic acid esters such as ethylene glycol diacetate and dimethyl adipate, and ketone compounds such as normal butyl methyl ketone, methyl ethyl ketone and isopropyl ethyl ketone. The usage-amount of a solvent is 1-10000 equivalent with respect to the aromatic compound which has a substituent of a raw material, Preferably it is 1-1000 equivalent.

  In the present invention, the reaction temperature of the oxidation dimerization reaction is preferably 50 to 300 ° C. More preferably, it is 150-260 degreeC, Since 180-250 degreeC can raise catalyst efficiency especially, it is preferable. If the reaction temperature is less than 50 ° C, the reaction rate is slow, which is not preferable. If the reaction temperature exceeds 300 ° C, by-products such as trimers other than biphenyls become prominent, and the amount of the target product is reduced. This is not preferable.

  The oxidation dimerization reaction of the present invention is performed in an atmosphere in which molecular oxygen is present. Although molecular oxygen may supply pure oxygen gas, in consideration of the risk of explosion, a mixed gas having an oxygen content of about 5 to 50% by volume diluted with an inert gas such as nitrogen gas or carbon dioxide gas or It is preferable for safety to use air. The reaction pressure of the oxidation dimerization reaction of the present invention is not limited, but an oxygen partial pressure of about 0.2 to 5 atm and an air pressure of about normal to 25 atm are suitable. Further, molecular oxygen may be contained in the reaction apparatus, or may be supplied into the reaction apparatus, particularly into the reaction mixture, and distributed in the reaction apparatus.

  In the present invention, the catalyst containing the rhodium compound may be added to the reaction raw material all at once, or may be added in multiple stages during the reaction. When adding in multiple stages, each component constituting the catalyst may be separately added and only one component may be added.

When the aromatic compound having a substituent is oxidatively dimerized by the method of the present invention, a symmetrically substituted biphenyl (meaning a biphenyl having a substituent at a symmetrical position on two benzene rings) and an asymmetrically substituted biphenyl are represented. A mixture of positional isomers consisting of (which means biphenyls having substituents at asymmetric positions on two benzene rings) is obtained, but the method of the present invention can selectively produce asymmetrically substituted biphenyls. Is one of the features.
For example, when the raw material is phthalic acid diester, 2,2 ′, 3,3′-biphenyltetracarboxylic acid tetraester is hardly formed, and 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester (A-BPTT) and 3,3 ′, 4,4′-biphenyltetracarboxylic acid tetraester (s-BPTT) are formed. In the method of the present invention, 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester can be selectively obtained as a main component.
The selectivity of such asymmetrically substituted biphenyls can be increased to 60 to 99 mol%, preferably 70 to 99 mol%, by selecting reaction conditions. The selectivity means the ratio of asymmetrically substituted biphenyls in the product, that is, (asymmetrically substituted biphenyls) / (symmetrically substituted biphenyls + asymmetrically substituted biphenyls) expressed as a percentage.

  The produced biphenyls can be separated and purified by known means such as distillation and crystallization operation. When the generated biphenyl is a-BPTT, it is hydrolyzed by a conventionally known method, for example, a method of hydrolyzing at a high temperature and a high pressure, or a method of hydrolyzing by adding an acid or an alkali to give 2,3, It can be 3 ′, 4′-biphenyltetracarboxylic acid. Furthermore, it can be dehydrated by heating to a high temperature to obtain 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride. This dianhydride is useful as one of monomer raw materials in the production of aromatic polyimide.

  The production method of the present invention can be used for any of batch operation, continuous operation, and semi-batch operation. The reaction apparatus may have any form corresponding to the above-described operation, but for example, a reaction apparatus such as a tank-type reaction apparatus, a tubular reaction apparatus, or a tower-type reaction apparatus can be suitably used. The material of the reactor is not particularly limited, and for example, a reactor made of glass or stainless steel can be suitably used.

  Hereinafter, the present invention will be described in more detail by way of examples. In addition, this invention is not limited only to these Examples.

  In the following examples, dimethyl phthalate was used as an aromatic compound having a substituent as a raw material. The products of the oxidation dimerization reaction at this time were 3,3 ′, 4,4′-biphenyltetracarboxylic acid tetraester (s-BPTT) and 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester ( a-BPTT). Here, the yield of the oxidized dimerization product, the catalyst turnover rate (TON), and the ratio of the amount of s-BPTT and a-BPTT (S / A) were calculated according to the following calculation formula.

Further, ¹ H-NMR was measured at room temperature using CD ₂ Cl ₂ as a solvent by AL-300 (300 MHz) manufactured by JEOL. The measurement results were expressed in the order of (chemical shift (ppm), splitting pattern (s = singlet, d = doublelet, br = broad, m = multiplet), integrated value) for each peak. Furthermore, the elemental analysis was measured using a microcoder JM10 type manufactured by J Science Lab. Numerical values are expressed in%.

  Of the rhodium compounds used in the following examples, tris (acetylacetonato) rhodium is converted to rhodium hydroxide from rhodium nitrate and then reacted with acetylacetone. The other rhodium compounds are trivalent rhodium halides. And the corresponding dicarbonyl compound and an enolate compound prepared from a base.

Furthermore, among the copper compounds used in the following examples, [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper (I) chloride was prepared according to Reference Example 1 below.
[Reference Example 1]
Synthesis of [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper (I) chloride In a 25 ml Schlenk tube, 298 mg of 1,3-bis (2,6-diisopropylphenyl) imidazolium chloride (0. 70 mmol), sodium t-butoxide 67.6 mg (0.70 mmol), and copper (I) chloride 73.4 mg (0.74 mmol) were added, and Ar gas substitution in the system was performed three times. To this was added 5 ml of anhydrous tetrahydrofuran as a solvent with a syringe and stirred at room temperature for 4 hours. After the reaction, insoluble materials were removed by Celite filtration, and the solvent was concentrated. By reprecipitation in a mixed solvent system of methylene chloride and diethyl ether, 246 mg (0.50 mmol, 71% yield) of [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper (I) chloride was obtained. Obtained as a white solid.
The NMR analysis and elemental analysis results of the obtained white solid were as follows.
The measurement results of ¹ H-NMR (CD ₂ Cl ₂ ) are (1.23, d, 12H), (1.28, d, 12H), (2.52-2.62, m, 4H), ( 7.18, s, 2H), (7.34, d, 4H), (7.53, dd, 2H).
Measurement of elemental analysis, C66.44, H7.28, (calcd _C 27 H 36 ClCuN ₂ is C66.51, H7.44, N5.75) _N5.77 was.

[Example 1]
1.27 g (6.5 mmol) of dimethyl phthalate and 20.3 mg (0.051 mmol) of tris (acetylacetonato) rhodium were weighed into a 20 ml glass pear-shaped flask and the Liebig condenser was placed in the flask. And a rubber balloon containing air of approximately 1 atm (the degree that the balloon inflates) was attached. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, a predetermined amount of cholesterol acetate was added as an internal standard substance, and quantitative analysis was performed by gas chromatography. As a result, the yield of oxidized dimer product was 2.8%, TON was 1.8, and S / A was 2/98.

[Example 2]
1.27 g (6.5 mmol) of dimethyl phthalate, 20.2 mg (0.050 mmol) of tris (acetylacetonato) rhodium and 3.2 mg (0.016 mmol) of copper acetate monohydrate Was weighed into a 20 ml glass pear-shaped flask, and a Liebig condenser and a rubber balloon containing air of about 1 atm (the degree that the balloon inflated) were attached to the flask. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, a predetermined amount of cholesterol acetate was added as an internal standard substance, and quantitative analysis was performed by gas chromatography. As a result, the yield of oxidized dimer product was 5.2%, TON was 3.4, and S / A was 3/97.

[Comparative Example 1]
The same reaction as in Example 2 was performed except that the reaction was performed in an argon atmosphere. As a result, the yield of the dimer product was 0.2%, the TON was 0.1, and the S / A was 11/89.

Example 3
1.27 g (6.5 mmol) of dimethyl phthalate and 18.0 mg (0.051 mmol) of chlorobis (acetylacetonato) rhodium monohydrate were weighed into a 20 ml glass pear-shaped flask. A Liebig condenser and a rubber balloon containing air at approximately 1 atm (the degree that the balloon inflates) were attached to the flask. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, a predetermined amount of cholesterol acetate was added as an internal standard substance, and quantitative analysis was performed by gas chromatography. As a result, the yield of oxidized dimer product was 2.9%, TON was 1.9, and S / A was 2/98.

Example 4
1.27 g (6.5 mmol) dimethyl phthalate, 17.6 mg (0.050 mmol) chlorobis (acetylacetonato) rhodium monohydrate and 3.2 mg (0.016 mmol) copper acetate. The monohydrate was weighed into a 20 ml glass pear-shaped flask, and a Liebig condenser and a rubber balloon containing air of approximately 1 atm (the degree that the balloon inflated) were attached to the flask. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, a predetermined amount of cholesterol acetate was added as an internal standard substance, and quantitative analysis was performed by gas chromatography. As a result, the yield of oxidized dimer product was 5.3%, TON was 3.4, and S / A was 3/97.

Example 5
1.27 g (6.5 mmol) dimethyl phthalate and 12.2 mg (0.025 mmol) di-μ-chlorobis (1,5-cyclooctadiene) dirhodium and 2.9 mg (0.015 mmol) Of copper acetate monohydrate and 4.9 mg (0.049 mmol) of acetylacetone was weighed into a 20 ml glass pear-shaped flask and the Liebig condenser and approximately 1 atm. A rubber balloon containing air was attached. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, and a predetermined amount of cholesterol acetate was added as an internal standard substance, followed by analytical quantification by gas chromatography. As a result, the yield of the oxidized dimer product was 3.3%, the TON was 2.2, and the S / A was 3/97.

Example 6
1.26 g (6.5 mmol) dimethyl phthalate, 12.4 mg (0.025 mmol) di-μ-chlorobis (1,5-cyclooctadiene) dirhodium and 2.9 mg (0.015 mmol) Of copper acetate monohydrate and 9.8 mg (0.097 mmol) of acetylacetone was weighed into a 20 ml glass pear-shaped flask and the Liebig condenser and approximately 1 atm. A rubber balloon containing air was attached. The flask was immersed in a silicon bath previously heated to 200 ° C. and stirred for 6 hours while circulating cooling water through a Liebig condenser. After the reaction, the flask was air-cooled, the reaction mixture was diluted with acetone, a predetermined amount of cholesterol acetate was added as an internal standard substance, and quantitative analysis was performed by gas chromatography. As a result, the yield of the oxidized dimer product was 4.0%, TON was 2.6, and S / A was 2/98.

Example 7
239 g (1.23 mol) of phthalic acid dimethyl ester and 40.5 mg (0.203 mmol) of copper (II) acetate monohydrate were added to a 300 ml separable flask, and a thermometer, Dimroth condenser, mechanical A stirrer and ball filter were attached. While stirring, air was blown from a ball filter at 130 ml / min, and the flask was immersed in a silicon oil bath while cooling water was circulated through the cooling pipe, and the temperature was raised from room temperature. Yellow solution prepared from 1.78 g (9.17 mmol) of raw material phthalic acid dimethyl ester and 53.4 mg (0.133 mmol) of catalyst component tris (acetylacetonato) rhodium at a reaction temperature of 80 ° C. The catalyst mixture (first stage) was added and the temperature was raised to 240 ° C. Stirring is continued for 2 hours at that temperature, and then the same amount of catalyst mixture of the same composition (second stage) is added and stirring is continued for another 2 hours. Eye) was added and stirred for 4 hours. After the reaction, the flask was air-cooled. The reaction mixture was diluted with methanol and water, and then quantitative analysis was performed by liquid chromatography. As a result, the yield of the oxidation dimerization reaction product was 4.5%, TON was 71, and S / A was 18/82.

Example 8
238 g (1.23 mol) of phthalic acid dimethyl ester and 97.5 mg (0.200 mmol) of [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper chloride prepared in Reference Example 1 ( I) was added to a 300 ml separable flask, and a thermometer, a Dimroth condenser, a mechanical stirrer, and a ball filter were attached. While stirring, air was blown from a ball filter at 130 ml / min, and the flask was immersed in a silicon oil bath while cooling water was circulated through the cooling pipe, and the temperature was raised from room temperature. Yellow solution prepared from 1.78 g (9.17 mmol) of raw material dimethyl phthalate and 53.4 mg (0.133 mmol) of catalyst component tris (acetylacetonato) rhodium at a reaction temperature of 80 ° C. The catalyst mixture (first stage) was added, and the temperature was raised to 220 ° C. Stirring is continued for 2 hours at that temperature, and then the same amount of catalyst mixture of the same composition (second stage) is added and stirring is continued for another 2 hours. Eye) was added and stirred for 4 hours. After the reaction, the flask was air-cooled. The reaction mixture was diluted with methanol and water, and then quantitative analysis was performed by liquid chromatography. As a result, the yield of the oxidation dimerization reaction product was 1.3%, the TON was 20, and the S / A was 22/78.

Example 9
238 g (1.23 mol) of phthalic acid dimethyl ester and 98.0 mg (0.201 mmol) of [1,3-bis (2,6-diisopropylphenyl) imidazolium] copper chloride prepared in Reference Example 1 ( I) was added to a 300 ml separable flask, and a thermometer, a Dimroth condenser, a mechanical stirrer, and a ball filter were attached. While stirring, air was blown from a ball filter at 130 ml / min, and the flask was immersed in a silicon oil bath while cooling water was circulated through the cooling pipe, and the temperature was raised from room temperature. Yellow solution prepared from 1.79 g (9.22 mmol) of raw material dimethyl phthalate and 53.4 mg (0.133 mmol) of catalyst component tris (acetylacetonato) rhodium at a reaction temperature of 80 ° C. The catalyst mixture (first stage) was added and the temperature was raised to 240 ° C. Stirring is continued for 2 hours at that temperature, and then the same amount of catalyst mixture of the same composition (second stage) is added and stirring is continued for another 2 hours. Eye) was added and stirred for 4 hours. After the reaction, the flask was air-cooled. The reaction mixture was diluted with methanol and water, and then quantitative analysis was performed by liquid chromatography. As a result, the yield of the oxidation dimerization reaction product was 4.0%, TON was 62, and S / A was 19/81.

  The reaction results of Examples 1 to 9 described above are summarized in Table 1 below. The catalyst amount is a mol% value relative to the raw material dimethyl phthalate.

The present invention provides a simple and novel production method for producing biphenyls, preferably regioselectively, by subjecting an aromatic compound having a substituent to an oxidative dimerization reaction. If this reaction is used, for example, 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester useful as a raw material for polyimide resin can be selectively obtained.

Claims (7)

  It is possible to selectively obtain 2,3,3 ′, 4′-biphenyltetracarboxylic acid tetraester by subjecting phthalic diester to an oxidation dimerization reaction using a catalyst containing a rhodium compound in an atmosphere containing molecular oxygen. A method for producing biphenyls characterized.   The method for producing biphenyls according to claim 1, wherein the catalyst containing a rhodium compound contains a rhodium compound and a copper compound.   The method for producing biphenyls according to claim 1, wherein the catalyst containing a rhodium compound contains a rhodium compound, a copper compound, and a β-diketone. The method for producing biphenyls according to any one of claims 1 to 3, wherein the rhodium compound is a compound represented by the following chemical formula (1).

(Wherein R ¹ and R ² represent an alkyl group or an aryl group, and the alkyl group or aryl group may have a substituent. X represents any atom of F, Cl, Br, or I) , N represents an integer of 1, 2 or 3.)   A method for producing biphenyls, comprising subjecting an aromatic compound having a substituent to an oxidation dimerization reaction using a catalyst containing a rhodium compound in an atmosphere containing molecular oxygen. The method for producing biphenyls according to claim 5, wherein the rhodium compound is a compound represented by the following chemical formula (1).

(Wherein R ¹ and R ² represent an alkyl group or an aryl group, and the alkyl group or aryl group may have a substituent. X represents any atom of F, Cl, Br, or I) , N represents an integer of 1, 2 or 3.) A catalyst for oxidation dimerization reaction of an aromatic compound, comprising a rhodium compound represented by the following chemical formula (1).

(Wherein R ¹ and R ² represent an alkyl group or an aryl group, and the alkyl group or aryl group may have a substituent. X represents any atom of F, Cl, Br, or I) , N represents an integer of 1, 2 or 3.)