KR100215636B1 - Process for producing polyhydroxybenzophenon - Google Patents

Abstract

[TECHNICAL FIELD OF THE INVENTION]

High-purity polyhydroxybenzophenone used as an ultraviolet absorber or the like is produced with high efficiency.

[Technical Problems to be Solved by the Invention]

The polyhydroxybenzophenone is safely produced at a high yield without using poison gas, and at the same time, the process is simplified and a polyhydroxybenzophenone of high purity is produced without a separate purification process.

[Summary of the Invention]

(Hydroxyphenyl) methane is produced by reacting polyhydroxybenzene with formalin in the presence of a base catalyst to prepare hydroxybenzylhydroxide, reacting the resulting compound with polyhydroxybenzene in the presence of an acid catalyst and a solvent, The resulting compound is oxidized with an oxidizing agent.

[Important Application of the Invention]

Ultraviolet absorber and photosensitive resin raw material.

Description

Production method of polyhydroxybenzophenone

The present invention relates to a polyhydroxybenzophenone represented by the following general formula (I) and more particularly to a polyhydroxybenzophenone represented by the following general formula (I), which is a known compound widely used as an ultraviolet absorbent and a photosensitive resin raw material, This invention relates to a method for easily producing a hydroxybenzophenone with high yield and high purity.

[In the general formula (I), n is an integer of 1 to 2]

The prior art for preparing the polyhydroxybenzophenone of the formula (I) is as follows.

U.S. Patent No. 2,854,484 and U.S. Patent No. 2,921,962 disclose a process for preparing a polyhydroxybenzophenone of the above formula (I) using an aromatic carboxylic acid and zinc chloride, phosphoric acid and phosphorus oxychloride, wherein a relatively high yield Of the population. However, the polyhydroxybenzophenone prepared by such a conventional method is difficult to obtain a product of good color, and there is a problem that a large amount of waste water containing phosphorus is generated.

The process for producing polyhydroxybenzophenone reported in Japanese Patent Application Laid-open No. 57-154140 is a process for producing polyhydroxybenzophenone in a relatively high yield by a process comprising reacting an aromatic carboxylic acid with a phenol in the presence of an alkyl sulfonic acid to be. However, the alkyl sulfonic acid used as a reagent is expensive, and it is necessary to use 5 equivalents of an alkyl sulfonic acid in one equivalent of an aromatic carboxylic acid, and a yield of about 20% is obtained when 1 equivalent is used.

The production process reported in U.S. Patent No. 2,694,729 is a process for producing 2, 2 ', 4, 4'-tetrahydrobenzophenone by reacting resorcinol dimethyl ether and phosgene in the presence of aluminum chloride using a solvent of hydrogen chloride as a solvent . However, this method is industrially difficult because the yield is as low as 35-40% and phosgene which is poison gas is used.

The production method reported in Japanese Patent Application Laid-Open No. 61-293945 is a process in which a polyhydroxybenzoester is subjected to a Fries rearrangement reaction using a metal halide catalyst.

Such a method can obtain polyhydroxybenzophenone with a relatively high yield, but the polyhydroxybenzoester must be prepared, which complicates the process and is not effective.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a process for producing polyhydroxybenzophenone of high purity without requiring additional purification steps, .

The present invention relates to a method for safely and efficiently producing a polyhydroxybenzophenone represented by the general formula (I) used as an ultraviolet absorber and a photosensitive resin raw material by a simple process.

More specifically, hydroxybenzyl hydroxide of formula (III) is prepared by reacting polyhydroxybenzene of formula (II) with formalin in the presence of a base catalyst to obtain a hydroxybenzyl hydroxide of formula (III) (Hydroxyphenyl) methane of the general formula (IV) is prepared by reacting benzylhydroxide with the polyhydroxybenzene of the general formula (II) in the presence of an acid catalyst and a solvent, Hydroxyphenyl) methane with an oxidizing agent to produce a polyhydroxybenzophenone represented by the general formula (I).

[In the general formulas (I) to (IV), n is an integer of 1 to 2)

The present invention will be described in more detail by dividing it into stages of the manufacturing process.

First, the hydroxybenzyl hydroxide of the formula (III) is prepared by reacting the polyhydroxybenzene of the formula (II) with formalin under a base catalyst. The base used herein is preferably at least one compound selected from the group consisting of caustic soda, soda ash and amine. The reaction temperature is 10 to 30 占 폚.

In the next step, the hydroxybenzylhydroxide compound of the formula (III) prepared in the above step is condensed with the compound of the formula (II) under an acid catalyst to obtain a bis (hydroxyphenyl) methane compound of the formula (IV) . The reaction formula is as follows.

[In the general formulas (II) to (IV), n is an integer of 1 to 2)

At this time, the solvent is preferably at least one compound selected from the group consisting of toluene, xylene and benzene, and the acid catalyst is preferably at least one compound selected from the group consisting of sulfuric acid, acetic acid and toluenesulfonic acid.

The reaction temperature is from 80 to 150 ° C.

As the last step, the polyhydroxybenzophenone of the general formula (I) is prepared by oxidizing bis (hydroxyphenyl) methane of the general formula (IV) prepared in the above process with an oxidizing agent. The reaction formula is as follows.

[In the general formulas (I) to (IV), n is an integer of 1 to 2)

At this time, chromium trioxide and acetic acid are used as the oxidizing agent, and the reaction temperature is preferably 0 to 30 ° C and the reaction time is preferably 12 to 36 hours.

Hereinafter, preferred embodiments of the present invention will be described.

However, this embodiment is a preferred embodiment of the present invention for facilitating the understanding of the invention, and does not limit the present invention.

[Example 1]

Preparation of di (2, 4-dihydroxyphenyl) methane

110 g (1 mol) of resorcinol is added to 500 ml of water and stirred. 200 ml of 5N-NaOH aqueous solution and 81 g (1 mol) of 37% formalin are added to the above-mentioned solution, and the mixture is stirred at room temperature for 12 hours. These solutions are neutralized with concentrated HCI. 1 liter of toluene is added to the neutralized solution, and the mixture is stirred and left to separate the toluene layer. To the separated toluene layer, 104 g (0.95 mol) of resorcinol and 1 ml of glacial acetic acid are added and reacted at 120 ° C. for 24 hours.

The water formed during the reaction is removed with a Dean Stark apparatus.

After completion of the reaction, the toluene is concentrated to 500 ml and then cooled to 60 ° C. Hexane was added thereto and the mixture was then dialyzed. The mixture was stirred at room temperature for 1 hour and filtered to obtain 198 g of di (2, 4-dihydroxyphenyl) methane. The yield was 85%.

[Example 2]

Preparation of 2, 2 ', 4, 4'-tetrahydroxybenzophenone

80% acetic acid 150 ml Chromium trioxide 120 g (1.2 mol) was added and dissolved, and the internal temperature of these solutions was cooled to 0 캜 to prepare an oxidizing agent solution.

On the other hand, a solution of 116 g (0.5 mol) of di (2,4-dihydroxyphenyl) methane dissolved in 600 ml of acetic acid is prepared and added dropwise to the oxidizing agent solution. After dropwise addition, the mixture was reacted at room temperature for 24 hours, 500 ml of water was added thereto, and the mixture was filtered to obtain 110 g of 2, 2 ', 4,4'-tetrahydroxybenzophenone. The yield was 90% and the melting point (mp) of the prepared compound was 202 to 203 占 폚.

When the polyhydroxybenzophenone is prepared by the method of the present invention, the purification process is omitted, and the production process is simple. There is no need to use the poison gas, so that the stability of the production process is improved and at the same time, the polyhydroxybenzophenone Phenone can be produced.

Claims (7)

The hydroxybenzylhydroxide of the formula (III) is prepared by reacting the polyhydroxybenzene of the formula (II) with the formalin in the presence of a base catalyst to obtain the hydroxybenzylhydroxide of the formula (III) (Hydroxyphenyl) methane of the general formula (IV) is prepared by reacting the bis (hydroxyphenyl) methane of the general formula (IV) with an oxidizing agent by reacting the polyhydroxybenzene of the general formula Wherein the polyhydroxybenzophenone of formula (I) is characterized by the following formula (I). [In the general formulas (I) to (IV), n is an integer of 1 to 2) The process for producing polyhydroxybenzophenone according to claim 1, wherein the base catalyst is at least one compound selected from the group consisting of caustic soda, soda ash and amine. The process for producing polyhydroxybenzophenone according to claim 1, wherein the reaction temperature of the compound of formula (II) and formalin is 10 to 30 占 폚. The process according to claim 1, wherein the acid catalyst is at least one compound selected from the group consisting of sulfuric acid, acetic acid, and toluenesulfonic acid. The process for producing polyhydroxybenzophenone according to claim 1, wherein the reaction temperature of the compound of formula (II) and the compound of formula (III) is 80 to 150 ° C. The method for producing polyhydroxybenzophenone according to claim 1, wherein chromium trioxide and acetic acid are used as an oxidizing agent. The process for producing polyhydroxybenzophenone according to claim 1, wherein the reaction temperature for oxidizing the compound of formula (IV) is from 0 to 30 ° C and the reaction time is from 12 to 36 hours.