JPS62298548A - Production of benzophenone or such - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a raw material for a positive type radiation-sensitive resin composition under a mild condition in high yield, by reacting a benzoic acid with a compound such as benzene, xylene, toluene, phenol, etc., in the presence of a sulfonic acid compound catalyst. CONSTITUTION:A benzoic acid derivative (e.g. gallic acid, etc.) shown by formula I (R<1>-R<5> are OH, H, 1-4C alkyl, 1-4C alkoxy, halogen, cyano, nitro or 2-5C acyl; X is H or 1-4C alkyl) is reacted with a compound (e.g. catechol, etc.) shown by formula II (R<6>-R<10> are OH, H, 1-4C alkyl, 1-4C alkoxy, halogen, cyano, nitro or 2-5C acyl) in the presence of a sulfonic acid compound (e.g. methanesulfonic acid, etc.) to give a benzophenone (e.g. 2,3,3',4',5'- pentahydroxybenzophenone, etc.). EFFECT:Operation is simple and waste water treatment is easy. USE:An antioxidant for rubber or plastics.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing benzophenones, and more particularly to a method for producing benzophenones using a benzoic acid derivative and a specific compound as starting materials.

[Conventional technology]

Benzophenones react with 1,2-quinonediazide compounds and are sensitive to radiation such as ultraviolet rays, X-rays, electron beams, molecular beams, T-rays, synchrotron beams, and proton beams, and are particularly suitable as resists for producing integrated circuits. It is a raw material used for positive radiation-sensitive resin compositions, and is also used for rubber,
It is a raw material for a useful anti-aging agent that can be mixed with plastics to prevent their deterioration.

Conventionally, these benzophenones are: ■Anhydrous aluminum chloride, ■Polyphosphoric acid - anhydrous zinc chloride -
It was produced by reacting benzoic acid derivatives with phenol derivatives using phosphorus trichloride or boron trifluoride as a catalyst.

[Problem that the invention seeks to solve]

However, the reaction using the above catalyst ■ or ■
Both are dehydrochlorination reactions, and there is a problem in that it is necessary to remove hydrogen chloride as a by-product. In other words, in the case of a reaction using anhydrous aluminum chloride as a catalyst, in addition to the need to treat hydrogen chloride after the reaction, gel-like aluminum hydroxide is produced by neutralizing aluminum chloride in water. , requiring removal from wastewater.

In addition, in the case of the reaction using polyphosphoric acid - anhydrous zinc chloride - phosphorus trichloride as a catalyst, it is not a resource-saving reaction as it requires a large amount of catalyst. Because of this, it is not possible to treat wastewater containing waste catalysts, which requires a lot of processing time.Furthermore, there are wastewater restrictions for zinc, and it is extremely difficult to separate and remove zinc hydroxide from wastewater. There was a problem. Furthermore, in the case of reactions using boron trifluoride as a catalyst, there is a problem that the water produced during the reaction reacts with boron trifluoride to produce hydrogen fluoride, which may corrode the reaction vessel. has.

The present invention was made against the background of the above-mentioned problems of the prior art, and it is possible to obtain benzophenones in a high yield (under mild reaction conditions and convenient reaction operations), and there is also the problem of disposal of by-products. It is an object of the present invention to provide a manufacturing method suitable for producing benzophenones, particularly hydroxybenzophenones, which does not generate waste water and which facilitates the treatment of wastewater containing waste catalysts.

[Means for solving problems]

That is, the present invention relates to the general formula (1) (where RI SRg , R3, R4 and R8 are the same or different, a hydroxyl group, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms) - halogen atom,
A cyano group, a nitro group, an acyl group having 2 to 5 carbon atoms, and X is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ) (hereinafter simply referred to as "benzoic acid derivative (I)")
'') and the general formula (n) (wherein R'', R', R'', R'' and R16 are the same or different, a hydroxyl group, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a carbon number 1 ~4 alkoxy groups, halogen atoms, cyano groups, nitro groups, and acyl groups having 2 to 5 carbon atoms, preferably at least one of R6, R?, R., R'' and RIO is a hydroxyl group.) The present invention provides a method for producing dibenzophenones, which comprises reacting a compound represented by (hereinafter simply referred to as "compound (■)") in the presence of a sulfonic acid compound.

The alkyl group having 1 to 4 carbon atoms includes, for example, a methyl group, ethyl group, propyl group, butyl group, etc.; the alkoxy group having 1 to 4 carbon atoms includes, for example, a methoxy group,
Ethoxy group, propoxy group, butoxy group, etc.; examples of halogen atoms include chlorine atom, bromine atom, etc.; examples of acyl groups having 2 to 5 carbon atoms include propionyl group, butyryl group, valeroyl group, etc.

The production method of the present invention comprises a benzoic acid derivative (1) and a compound (
II) is esterified with a specific catalyst, a sulfonic acid compound, to obtain benzophenones.

Examples of the benzoic acid derivative (I) include benzoic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 4-methoxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, and 4-methoxybenzoic acid. -3-nitrobenzoic acid, 0-nitrobenzoic acid, m-nitrobenzoic acid,
p-nitrobenzoic acid, O-chlorobenzoic acid, m-chlorobenzoic acid, p-chlorobenzoic acid, 2,3-dichlorobenzoic acid, 2.4-dichlorobenzoic acid, 2.5-dichlorobenzoic acid, 2. 6-dichlorobenzoic acid, 3.4-dichlorobenzoic acid, 3.5-dichlorobenzoic acid, 2-chloro-3
-Nitrobenzoic H12-chloro-4-nitrobenzoic acid,
2-chloro-5-nitrobenzoic acid, 3-chloro-2-nitrobenzoic acid, 4-rioo-2-nitrobenzoic acid, 4-
Chloro-3-nitrobenzoic acid, 2,4-dihydroxybenzoic acid, methyl benzoate, ethyl benzoate, methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate,
Propyl p-hydroxybenzoate, 2.4-dinitrobenzoic acid, 2.5-dinitrobenzoic acid, 3.4-dinitrobenzoic acid, 3,5-dinitrobenzoic acid, 2.5-dihydroxybenzoic acid, 2.6 -dihydroxybenzoic acid, 3,
4-dihydroxybenzoic acid, 3.5-dihydroxybenzoic acid, 2゜4-dimethylbenzoic acid, 2,5-dimethylbenzoic acid, 2.6-dimethylbenzoic acid, 3,4-dimethylbenzoic acid, 3.5- Dimethylbenzoic acid, 2,3-dimethoxybenzoic acid, 2.4-dimethoxybenzoic acid, 2.6-
Dimethoxybenzoic acid, 3.4-dimethoxybenzoic acid, 3
．． 5-dimethoxybenzoic acid, 2,6-difluorobenzoic acid, methyl m-nitrobenzoate, methyl p-nitrobenzoate, ethyl m-nitrobenzoate, ethyl p-nitrobenzoate, 3-nitro-4-hydroxybenzoate Acid, methyl 3-hydroxybenzoate, ethyl O-hydroxybenzoate, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate, 0-fluorobenzoic acid, m-fluorobenzoic acid, p-fluorobenzoic acid, p- Ethyl fluorobenzoate, 0-bromobenzoic acid, m-bromobenzoic acid,
p-bromobenzoic acid, 5-bromo-2-hydroxybenzoic acid, 〇-iodobenzoic acid, m-iodobenzoic acid, p-
iodobenzoic acid, 2,3.4-)dimethoxybenzoic acid,
Examples include 2.4.5-trimethoxybenzoic acid, 3,4.5-trimethoxybenzoic acid, 2.4.6-1-dihydroxybenzoic acid, and gallic acid.

In addition, benzoic acid derivatives (■), such as gallic acid,
Usually, in order to have water of crystallization, prior to the reaction, under reduced pressure, for example, 1 to 50 flHg and a temperature of 40 to 100 °
It is desirable to dry it for about an hour to remove the water of crystallization.

In addition, as the compound (n), benzene, xylene, toluene, phenol, O-chlorophenol, m-chlorophenol, p-chlorophenol, O-bromophenol, m-bromophenol, p-bromophenol, O-iodo Phenol, m-iodophenol, p-
Iodophenol, 0-fluorophenol, m-fluorophenol, p-fluorophenol, 0-methoxyphenol, m-methoxyphenol, p-methoxyphenol, 0-ditrophenol, m-ditrophenol, p-nitrophenol , 2-isopropylphenol, 3-isopropylphenol, 4-isopropylphenol, 0-cresol, m-cresol, p-cresol, 〇-ethylphenol, m-ethylphenol, p-ethylphenol, 2,4-dinitrophenol, 2.5-dinitrophenol, 2.6-dimethoxyphenol, 3,5-dimethoxyphenol, 2.6-
Diituprobylphenol, 2.3-dimethylphenol, 2.4-dimethylphenol, 2.5-dimethylphenol, 2.6-dimethylphenol, 3,4-dimethylphenol, 3゜5-dimethylphenol, 2, 3
-dichlorophenol, 2,4-dichlorophenol,
2,5-dichlorophenol, 2,6-dichlorophenol, 3,4-dichlorophenol, 3,5-dichlorophenol, 2-bromo-4 methylphenol, 4-bromo 2,6-dimethylphenol, 4-bromo 3 ．．
5-dimethylphenol, 4-chloro-2-methylphenol, 4-chloro-3-methylphenol, 2-chloro-6-methylphenol, 2-methyl-3-nitrophenol, 2-methyl-5-nitrophenol Phenol, 3-methyl-5-ditrophenol, 3-methyl-4-ditrophenol, 3-methyl-3-ditrophenol, 5-
Methyl-2-methylphenol, 2.3゜5-trichlorophenol, 2.3.6-)lichlorophenol, 2.
4.5-) dichlorophenol, 2. 4. 6-) Dichlorophenol, 3.4゜5-trichlorophenol, 2,4.6-) Lifluorophenol, 2.3.5-
Trifluorophenol, 2.3.6-trimethylphenol, 2.4.6-)dimethylphenol, 2,6-
Dipromo-4-methylphenol, 2-chloro-4゜5
-dimethylphenol, resorcinol, catechol,
Hydroquinone, 4.6-dichloro-resorcin, 5-methylresorcin, 4-methylcatechol, 4-chloro-
Examples include resorcinol, pyrogallol, 1.2.4-)lyhydroxybenzene, and 1,3°5-trihydroxybenzene.

In the reaction of the present invention, for example, a benzoic acid derivative (
1) and compound (II) are allowed to coexist, and a sulfonic acid compound as a catalyst is added thereto to carry out the reaction.

Examples of the sulfonic acid compound used as a catalyst include methanesulfonic acid, sulfuric acid, chlorosulfonic acid, fluorosulfonic acid, bromosulfonic acid, methanesulfonic acid,
Examples include methanesulfonyl chloride, methanesulfonyl chloride, trifluoromethanesulfonic acid, trichloromethanesulfonic acid, p-toluenesulfonic acid, chlorinated toluenesulfonic acid, and fluorinated p-toluenesulfonic acid.

The reaction ratio of benzoic acid derivative (1) and compound (II) is usually 1 mole of compound (■) to 1 mole of benzoic acid derivative (■).
1) is 0.8 to 1.2 mol, preferably 1.0 to 1.0 mol
5 mol, and if the benzoic acid derivative (1) is less than 0.8 mol, the yield of benzophenones produced will decrease significantly,
On the other hand, if the amount exceeds 1.2 mol, a step for recovering unreacted benzoic acid derivatives must be introduced, resulting in a decrease in productivity.

In addition, the amount of the sulfonic acid compound used as a catalyst is usually 0.2 to 3 mol, preferably 1 to 2 mol, per 1 mol of compound (■). On the other hand, if the amount exceeds 3 moles, a large excess of the sulfonic acid compound must be disposed of after the reaction, leading to an increase in cost.

In the reaction, a solvent is usually used, and examples of the solvent include nitrobenzene, monochlorobenzene,
Dichlorobenzene, carbon disulfide 11゜2-dichloroethane, 1.1.2.2-tetrachloroethane, 1.1.3-
) Inert solvents used in free-sol fluorocarbon reactions such as dichloroethane, 1°2-bromoethane, and trichlorobenzene are used.

The amount of this solvent to be used is usually from the same amount to 20 times, preferably 5 to 10 times, but less than the same amount, relative to the total amount of the benzoic acid derivative (1) and compound (II). If it is, the reactivity will be lowered, and the yield of the produced benzophenones will be lowered. On the other hand, if the magnification exceeds 20 times, the productivity will be lowered due to the need to recover the solvent after the reaction is completed.

The reaction temperature in the present invention is usually 20 to 170°C, preferably 50 to 130'C; if it is less than 20'C, the reaction will not proceed sufficiently, while if it exceeds 170'C, side reactions will increase. The yield of the target benzophenones will drop significantly.

After the reaction, hydroxybenzophenones are produced in the form of a precipitate, and when this reaction solution is poured into a large amount of ice water, the remaining benzoic acid derivative (I) and the compound (n
) and the sulfonic acid compound as a catalyst are dissolved in water, so the production and recovery of the hydroxybenzophenones can be carried out simultaneously. Furthermore, hydroxybenzophenones can also be purified by dissolving them in the above-mentioned solvent and then adding them to a non-solvent such as water, hydrocarbon, etc. for reprecipitation.

The benzophenones obtained in the present invention include (in the formula,
RI SR2, R3, R4, R5, Rh, R7, RI
SR1 and R10 are the same as above. ), such as benzophenone, 2
-Hydroxybenzophenone, 3-hydroxybenzophenone/4-hydroxybenzophenone, 3-chloro-
4-hydroxybenzophenone, 2-chloro-4-hydroxybenzophenone, 3-iodo-4-hydroxybenzophenone, 3-bromo-4-hydroxybenzophenone, 3-fluoro-4-hydroxybenzophenone,
3-methoxy-4-hydroxybenzophenone, 4-chloro-4'-hydroxybenzophenone, 3-nitro-
4-hydroxybenzophenone, 2-methyl-4-hydroxybenzophenone, 2.3-dihydroxybenzophenone, 2.4-dihydroxybenzophenone, 2.5
-dihydroxybenzophenone, 2,6-dihydroxybenzophenone, 4.4'-dihydroxybenzophenone, 2.2'-dihydroxybenzophenone, 2.3'
-dihydroxybenzophenone, 2.4'-dihydroxybenzophenone, 2.2'.

3-trihydroxybenzophenone, 2.3.4-trihydroxybenzophenone, 2,3.5-trihydroxybenzophenone, 2,3.6-trihydroxysozophenone, 2,4.6-)dihydroxybenzophenone, 2.3 .3'-)dihydroxybenzophenone, 2,
3.4'-1-dihydroxybenzophenone, 2.2'
, 4-) dihydroxybenzophenone, 2.3', 4-
Trihydroxybenzophenone, 2,4.4'-)dihydroxybenzophenone, 2.2',5-trihydroxybenzophenone, 2.3',5-)dihydroxybenzophenone, 2.4',5-trihydroxybenzophenone, 2. 2',6-trihydroxybenzophenone,
2.3',6-)dihydroxybenzophenone, 2.4
', 6-) dihydroxybenzophenone, 2.2', 3
．． 4-tetrahydroxybenzophenone, 2,3.3'
.

4-tetrahydroxybenzophenone, 2.3°4.4
'-Tetrahydroxybenzophenone, 2°2', 4.
5-tetrahydroxybenzophenone, 2.3', 4.
5-tetrahydroxybenzophenone, 2.4.4',
5-tetrahydroxybenzophenone, 2.2', 4.
6-tetrahydroxybenzophenone, 2.3', 4.
6-tetrahydroxybenzophenone, 2.4.4',
6-tetrahydroxybenzophenone, 2.2', 3°3'-tetrahydroxybenzophenone, 2.2'.

3.4'-tetrahydroxybenzophenone, 2゜2'
, 3.5'-tetrahydroxybenzophenone, 2.2
', 3.6'-tetrahydroxybenzophenone, 2,
3.3',4'-tetrahydroxybenzophenone, 2
．． 3.3',5'-tetrahydroxybenzophenone,
2.3.3',6'-tetrahydroxybenzophenone, 212'+3.4.4'-pentahydroxybenzophenone, 2.2',3.4.5'-pentahydroxybenzophenone, 2.2',3. 4.6'-pentahydroxybenzophenone, 2,3.3', 4.4'-pentahydroxybenzophenone, 212'13.3', 4.
4'-hexahydroxybenzophenone, 2.3.3'
, 4.4',5'-hexahydroxybenzophenone,
2.2', 3.4゜4', 6'-hexahydroxybenzophenone, 2.2', 4.4', 6-pentahydroxybenzophenone, 2.2', 4.5'', 6-pentahydroxy Benzophenone, 2.2', 4.6.6'-pentahydroxybenzophenone, 21'3'14.4'
, 6-pentahydroxybenzophenone, 2.3', 4
．． 5',6-pentahydroxybenzophenone, 2.3
', 4.4', 5', 6-hexahydroxybenzophenone, 2.2', 4°4', 6.6'-hexahydroxybenzophenone, 2.2', 3.4.5-pentahydroxy Benzophenone, 2,3.3', 4.5-pentahydroxybenzophenone, 2.3,4.4', 5-pentahydroxybenzophenone, 2,3.3'4', 5
'-Pentahydroxybenzophenone, 2.2', 3.
4.5.5'-hexahydroxybenzophenone, 2.
2',3,4,5.6'-hexahydroxybenzophenone, 2,3.3'.

4.4',5-hexahydroxybenzophenone, 2.
3.3', 4,5.5'-hexahydroxybenzophenone, 2.2', 3.3', 4.4'.

5-heptahydroxybenzophenone, 2.3°3',
4.4', 5.5'-hebutahydroxybenzophenone, 2.2', 3,4.4', 5.6'-hebutahydroxybenzophenone, 2.2'.

3.4.4'-pentahydroxy-5-methylbenzophenone, 2.2', 3.4.4'-pentahydroxy-
5-ethylbenzophenone S 2+ 2' +3.
4.4'-pentahydroxy-5-n-propylbenzophenone, 2.2',3,4.4'-pentahydroxy-5-n-butylbenzophenone, 2.2',3,4.
5'-pentahydroxy-5-methylbenzophenone,
2.2', 3.4゜5'-pentahydroxy-5-n-
Propylbenzophenone, 2.2', 3.4.6'-Pentahydroxy-5-methylbenzophenone, 2.2'
.

3.4.6'-pentahydroxy-5-n-propylbenzophenone, 2,3.3',4.4'-pentahydroxy-5-methylbenzophenone, 2.3.3',4.
4'-Pentahydroxy-5-n-propylbenzophenone, 2.3.3'.

4.5'-pentahydroxy-5-methylbenzophenone, 2,3.3',4.5'-pentahydroxy-5-
n-propylbenzophenone, 2°2', 3.3', 4
．． 4'-hexahydroxy-5-methylbenzophenone, 2.2', 3.3'.

4.4'-hexahydroxy-5-n-propylbenzophenone, 2.3.3', 4.4', 5'-hexahydroxy-5-methylbenzophenone, 2.3.3', 4
．． 4',5'-hexahydrox:/-5-n-propylbenzophenone, 2.2'.

3.4.4', 6'-hexahydroxy-5-methylbenzophenone, 2.2', 3.4.4'.

6'-hexahydroxy-5-n-propylbenzophenone, 2.2', 3.3', 4'-pentahydroxy-
4 niethoxybenzophenone, 2°2', 3.3',
4'-pentahydroxy-4-n-propoxybenzophenone, 2.2', 3°3', 4'-pentahydroxy-4-n-butylbenzophenone, 2.3.3', 4'
, 5'-pentahydroxy-4-methoxybenzophenone, 2.3.3',4',5'-pentahydroxy-4
-n-propoxybenzophenone, 2.2'.

3.4', 6'-pentahydroxy-4-methoxybenzophenone, 2.2', 3.4', 6'-pentahydroxy-4-n-propoxybenzophenone, 2.2',
3.4.4'-pentahydroxy-5-chlorobenzophenone, 2.2', 3°4.4'-pentahydroxy-
5-bromobenzophenone, 2.2', 3.4.4'-
Pentahydroxy-5-bromobenzophenone, 2.2
'.

3.4.6'-pentahydroxy-5-chlorobenzophenone, 2.2', 3.4.6'-pentahydroxy-
5-bromobenzophenone, 2,3°3', 4.4',
5'-hexahydroxy-5-chlorobenzophenone,
2, 3.3', 4.4'.

5'-hexahydroxy-5-bromobenzophenone,
2.2', 3.4.4'-pentahydroxy-5-cyanobenzophenone, 2.3.3'.

4.4', 5'-hexahydroxy-5-cyanobenzophenone, 2.2', 3.4.4'-pentahydroxy-5-nitrobenzophenone, 2°3.3', 4.4'
, 5'-hexahydroxy-5-nitrobenzophenone, 2.3', 4.4'.

5'-pentahydroxy-5-acetylbenzophenone, 2.3', 4.4', 5'-pentahydroxy-5-
Benzoylbenzophenone, 2.3°3', 4.4',
5'-hexahydroxy-5-acetylbenzophenone, 2,3.3', 4.4'.

5'-hexahydroxy-5-benzoylbenzophenone, 2.3', 4.4', 5'-pentahydroxy-5
-benzylbenzophenone, 2,3°3', 4.4',
Examples include 5'-hexahydroxy-5-benzylbenzophenone.

〔Example〕

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

Example 1 40 g of monochlorobenzene was placed in a 100 ml separable flask equipped with a stirrer and a condenser.
Next, 7.53 g (0.04 mol) of gallic acid was added to this.
and 4.40 g (0.04 mol) of catechol and 7.68 g of methanesulfonic acid (catalyst) were added with stirring.
0.08 mol) was added. After adding methanesulfonic acid, the temperature of the reaction system was raised to 70°C, and the reaction was then carried out at 70±5°C for 6 hours, and a product was precipitated. After the reaction was completed, monochlorobenzene was separated from the precipitate by decantation, and the precipitate was dissolved in 100 ml of acetone. Ion exchanged water while stirring this acetone solution 1.80
The mixture was poured into 0 mf and solidified. This coagulated material was separated by filtration, collected, and washed with water to remove unreacted gallic acid and catechol as well as the catalyst methanesulfonic acid.

As a result, 9.4 g of 2,3.3',4',5'-pentahydroxybenzophenone was obtained, with a yield of 90%.
Met.

Example 2 Pyrogallol 5.04g (0.04g instead of catechol)
The procedure was as in Example 1, except that trifluoromethanesulfonic acid 12, Og (0.08 mol) was used as a catalyst instead of methanesulfonic acid.

As a result, 2. 3. 3', 4. 4', 5
8.3 g of '-hexahydroxybenzophenone was obtained, with a yield of 75%.

Example 3 The same procedure as in Example 2 was carried out except that the amount of trifluoromethanesulfonic acid used as the catalyst in Example 2 was changed to 6.0 g (0.04 mol).

As a result, 8.2 g of 2,3.3',4.4',5'-hexahydroxybenzophenone was obtained, with a yield of 7.
It was 4%.

Example 4 The gallic acid used in Example 2 was heated at 80°C for 6 hours under reduced pressure (1~
Dried gallic acid (50 mHg) and water of crystallization removed (
(hereinafter referred to as "dry gallic acid") was obtained.

The same procedure as in Example 2 was carried out except for using 6.86 g (0.04 mol) of this dry gallic acid.
10.0 g of 3',4.4',5'-hexahydroxybenzophenone was obtained, with a yield of 90%. As a result, it was found that the yield was higher than that of the esterification reaction in Example 2 using gallic acid that had not been dried under reduced pressure.

Example 5 6.86g (0,0(
The procedure was repeated in the same manner as in Example 2, except that the reaction time was 3 hours.
8.7 g of 5'-hexahydroxybenzophenone was obtained, with a yield of 78%.

Comparative Example 1 90 g of monochlorobenzene was placed in a separable flask with a capacity of 200 m1 equipped with a stirrer and a condenser.
Next, 18.82 g (0.1 mol) of gallic acid was added to this.
and 12.61 g (0.1 mol) of pyrogallol were added,
While stirring, 21.29 g (0.15 mol) of boron trifluoride ethyl ether complex as a catalyst was added. After adding boron trifluoride ethyl ether complex, the reaction system was heated to 70°C.
When the mixture was heated to 70±5° C. for 5 hours, a product was precipitated. The operation after the completion of the reaction was carried out in the same manner as in Example 1, and 2.7 g of 2,3.3'4',5'-hexahydroxybenzophenone was obtained with a yield of 9.7%. Ta.

Furthermore, after the reaction, the inner surface of the separable flask serving as the reaction vessel was cloudy white and corroded.

Comparative Example 2 Comparative Example 1 except that the amount of boron trifluoride ethyl ether complex used as the catalyst in Comparative Example 1 was 35.48 g (0.25 mol), the reaction temperature was 130°C, and the reaction time was 3 hours. operated in the same way.

As a result, 12.4 g of 2,3.3',4.4',5'-hexahydroxybenzophenone was obtained, and the yield was 44.6%. Furthermore, after the reaction, the inner surface of the separable flask serving as the reaction vessel was observed to be cloudy and corroded.

The above results show that the production method of the present invention can obtain benzophenones in high yield and does not corrode the reaction vessel.

〔Effect of the invention〕

According to the present invention, benzophenones can be obtained in high yield under mild reaction conditions and through convenient reaction operations, and there are no problems with the treatment of generated products, and wastewater containing waste catalyst can be treated easily. It's easy.

Claims (1)

[Claims] (1) General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1, R^2, R^3, R^4 and R^5
are the same or different, hydroxyl group, hydrogen atom, carbon number 1-4
an alkyl group, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a cyano group, a nitro group, an acyl group having 2 to 5 carbon atoms,
X is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ) and the general formula (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, R^6, R^7, R^8, R^9 and R^ 1
^0 is the same or different, hydroxyl group, hydrogen atom, carbon number 1
-4 alkyl groups, C1-4 alkoxy groups, halogen atoms, cyano groups, nitro groups, and C2-5 acyl groups. ) in the presence of a sulfonic acid compound.