JPS61293945A - Production of polyhydroxybenzophenone - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as an ultraviolet light absorber in high yield with slight coloring, by subjecting a hydroxybenzoate to the Fries rearrangement in the presence of a specific catalyst. CONSTITUTION:A hydroxybenzoate expressed by formula I [R is alkyl, alkoxy or halogen; Rs may be the same or different substituent groups when >=2 R groups are present (n is >=2 and/oer q is >=2); m and p are integers 1-5; n and q are 0 or integers 1-4; m+n is <=5 and p+q is <=5) as a raw material is subjected to Fries rearrangement in the presence of at least one selected from zirconium halides, iron halides, zinc halides, tin halides and bismuth halides, preferably in a molar amount of about 0.1-4 times, particularly about 0.2-2 times based on one mol raw material compound at about 0-120 deg.C, particularly 30-90 deg.C to afford the aimed compound expressed by formula II.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing polyhydroxybenzophenone. More particularly, the present invention relates to a method for producing polyhydroxybenzophenone with high yield and less coloring by subjecting hydroxybenzoate to Fries rearrangement.

2.2,4.4-tetrahydroxybenzophenone, 2
．． Polyhydroxybenzophenones such as 2-dihydroxy-4,4-dimethoxybenzophenone are used as ultraviolet absorbers. Conventionally, methods for producing polyhydroxybenzophenones have been described, for example, in U.S. Pat. No. 2,854.
．． 485 and 2,921,962, a method is known in which aromatic carboxylic acid and phenol are reacted in the presence of zinc chloride, phosphoric acid, and phosphorus oxychloride or phosphorus trichloride. There is.

Although the specification of this US patent states that polyhydroxybenzophenone can be produced in good yield, according to the experience of the present inventors, this method can produce polyhydroxybenzophenone in high yield and with less coloring. It is difficult to obtain polyhydroxybenzophenone, and in addition, there are difficulties in treating wastewater containing phosphorus, and this method has not been satisfactory as an industrial method for producing polyhydroxybenzophenone.

Further, Tokusho No. 57-164140 discloses a method of reacting aromatic carboxylic acid and phenol in the presence of alkanesulfonic acid, but in addition to the fact that the alkanesulfonic acid used is expensive, In order to obtain polyhydroxybenzophenone in a relatively high yield, it is necessary to use 5 or more moles of alkanesulfonic acid per mole of aromatic carboxylic acid. The use of alkanesulfonic acid in an equimolar amount to the aromatic carboxylic acid has the disadvantage that polyhydroxybenzophenone can only be obtained in a yield of about 20%.

Further, as another method for obtaining polyhydroxybenzophenone, US Pat. No. 2,694,729 describes a method in which resorcinol dimethyl ether and phosgene were reacted in the presence of aluminum chloride using a chlorinated hydrocarbon as a solvent. Afterwards, demethylation was performed to obtain 2.2', 4.4'-
One method has been disclosed for obtaining tetrahydroxybenzophenone, but the yield is as low as about 85-40%, making it unsuitable for industrial implementation.

[Means for solving problems]

In view of this situation, the present inventors have conducted intensive studies on an industrial production method for polyhydroxybenzophenone, and as a result, the present inventors have developed a method for producing polyhydroxybenzophenone in high yield by subjecting hydroxybenzoate to Fries rearrangement in the presence of a specific catalyst. The present invention was completed based on the knowledge that polyhydroxybenzophenone can be obtained with high yield and less coloring. That is, the present invention applies to the general formula (R represents an alkyl group, an alkoxy group, or a halogen atom, and when 几 is 2 or more (n≧2 and/or q≧2), the substituents may be the same or different substituents. Good. m and p are integers of 1 to 5, n and q are integers of 0 or 1 to 4,
m-)-n≦5 and p+q≦5. ) is subjected to Fries rearrangement (Fr1es) using at least one selected from zirconium halide, iron halide, zinc halide, tin halide, and bismuth halide as a catalyst. (Ps q, m+n, p+q are the same as defined above.) This is a method for producing polyhydroxybenzophenone represented by:

The present invention will be explained in detail below.

The hydroxybenzoate used in the invention can be obtained by reacting hydroxybenzene with phosgene without a catalyst or in the presence of a halogenated zirconium catalyst.

The hydroxybenzene used in this reaction is LJ (in the formula, R represents an alkyl group, an alkoxy group, or a halogen atom, and when j is 2 or more (j≧2), the substituents may be the same or different. .Dish is an integer from 1 to 5, j
is 0 or an integer from 1 to 4, and i −4−j≦5. ) is a compound represented by R is an alkyl group having 1 to 12 carbon atoms such as a methyl group, ethyl group, propyl group, butyl group, or octyl group, or an alkyl group having 1 to 12 carbon atoms such as a methoxy group, a nidoxy group, a propoxy group, a butoxy group, an octofluoroxy group, etc. Examples include alkoxy groups, group elements, and halogen atoms such as chlorine, bromine, and iodine. Also, j is 2
In the case where the above integers are indicated, each substituent may be the same substituent or a different type of substituent. Examples of the compound represented by the above general formula include catechol, resorcin, hydroquinone, 1,2°3-trihydroxybenzene, resorcin monomethyl ether, resorcin monooctyl ether, and 8,6-hydroxytoluene. hydroxybenzene,
Both phosgenes can be purified to a high degree of purity, or can be used in their industrially produced form.

The method of the present invention can be carried out without a catalyst or with a zirconium halide as a catalyst.

As the zirconium halide, chloride and/or bromide or a mixture thereof is preferably used.

Hydroxybenzene and phosgene are generally reacted in the presence of a solvent. That is, in the case of no catalyst, hydroxybenzene is dissolved or suspended in a solvent, or
When using zirconium halide as a catalyst, a method is generally adopted in which hydroxybenzene and zirconium halide are dissolved or suspended in a solvent and phosgene is blown into the mixture to react. As the solvent, carbon disulfide, nitrobenzene, 1°2-dichloroethane, chlorobenzene, bromobenzene, 0-dichlorobenzene, m-dichlorobenzene, etc. can be used.

When carrying out the reaction without a catalyst, the amounts of hydroxybenzene, solvent, and phosgene to be used are as follows: General iC hydroxybenzene is added to the solvent at a ratio of about 8 to 40% by weight, and the amount of phosgene used is based on the theoretical amount of hydroxybenzene. The amount used is about 0.5 to 8 moles, preferably about 1 to 4 moles, and the reaction temperature is generally about 50 DEG to 150 DEG C., preferably about 70 DEG to 180 DEG C. When the degree of hydroxybenzene in the solvent exceeds about 40%, the proportion of by-products produced increases, while when the concentration decreases, productivity deteriorates. Further, even if a large amount of phosgene is used, a commensurate effect cannot be obtained, so it is generally used in an amount of about 0.5 to 8 times the amount, preferably about 1 to 4 times the amount. Regarding the reaction temperature, if the temperature is above a suitable temperature range, the amount of by-products will increase significantly, while if it is below a suitable temperature range, it will take a long time to complete the reaction.

When using zirconium halide as a catalyst,
The amounts of hydroxybenzene, solvent, and phosgene to be used may be the same as in the case of no catalyst, and the amount of zirconium halide used as a catalyst is about 0.05 to 2 times the mole of hydroxybenzene, preferably about 0.1 to 2 times. The reaction temperature is generally about 0 to 90°C, preferably about 20°C.
It is carried out at ~50°C. If the amount of zirconium halide used is approximately twice the mole or more, or if the temperature exceeds a suitable temperature range, the increase in by-products will be negligible and the proportion of hydroxybenzoate produced will decrease. If the amount is less than about 0.1 times the mole, or if the temperature is below the preferred range, it will take a long time to complete the reaction.

The time for blowing phosgene may be within a range that does not cause abnormal heat generation due to the blowing. After the introduction of phosgene, it is effective to provide an aging time of about 1 to 20 hours to complete the reaction.

The hydroxybenzoate produced by the reaction can be isolated by washing the reaction product with water to remove unreacted hydroxybenzene, then evaporating and recovering the solvent, and performing concentration crystallization. Hydroxybenzoate with less coloring can be obtained by concentration crystallization, but if desired, further purification such as recrystallization can be carried out.

Hydroxybenzoates obtained in this way include 8-hydroxyphenyl-2,4-dihydroxybenzoate, 2-hydroxyphenyl-8,4-dihydroxybenzoate, and 4-hydroxyphenyl-2, depending on the hydroxybenzene used in the reaction. ,6-dihydroxybenzoate 2-hydroxyphenyl-2,4-dihydroxybenzoate 8-hydroxyphenyl-8,4-dihydroxybenzoate 4-hydroxyphenyl-2,4-dihydroxybenzoate 8-hydroxyphenyl-2,5-dihydroxybenzoate 2 -Hydroxyphenyl-2,5-dihydroxybenzoate 4-Hydroxyphenyl-8,4-dihydroxybenzoate 2.8-Dihydroxyphenyl-2,8,4-trihydroxybenzoate (8-hydroxy-5-methyl)phenyl-(2 ,4-
Examples include dihydroxy-6-methyl)benzoate, 8-methoxyphenyl-(2-hydroxy-4-methoxy)benzoate, and the like.

The hydroxybenzoate obtained as described above is subjected to a Fries rearrangement reaction in the presence of a specific catalyst to produce polyhydroxybenzophenone.

Examples of the catalyst include at least IN selected from zirconium halides, iron halides, zinc halides, tin halides, and bismuth halides.

Preferably, at least one selected from zirconium, zinc, tin chloride and/or bromide is used.

It is also possible to add a protic acid such as hydrogen chloride together with the catalyst.

By using these catalysts, fleece (Fr1e
s) The rearrangement proceeds smoothly, and the desired 9-polyhydroxybenzophenone with little coloration can be obtained in high yield.

As the hydroxybenzoate used in the Fries rearrangement reaction, the above-described main reaction liquid of hydroxybenzene and phosgene can be used as it is.

It is also possible to isolate hydroxybenzoate from the reaction product solution and provide it. In order to avoid the complexity of reaction operations, it is common industrially to use the reaction product liquid as it is.

The amount of catalyst for Fries rearrangement is about 0.1 to 4 times the mole of hydroxybenzoate present, preferably about 0.
．． 2 to 2 times the mole amount is used. If the amount of catalyst used exceeds about 4 times the mole, there will be a problem in terms of economy, and if the amount of catalyst used exceeds about 0.
If it is less than 1 mole, rearrangement will not proceed sufficiently, which is not preferable.

The reaction temperature is generally about 0-120°C, preferably about 30-120°C.
Performed at 90°. If the reaction temperature is about 120° C. or higher, the resulting polyhydroxybenzophenone will become highly colored, which is undesirable in terms of hue. Although there is no limit to the reaction time, generally a reaction time of about 0.5 to 20 hours is employed.

The polyhydroxybenzophenone produced by the reaction can be obtained by dropping cold water into the reaction product or by pouring the product into cold water, and then separating and purifying the precipitated polyhydroxybenzophenone using conventional separation and purification methods such as filtration, water washing, and recrystallization. The target polyhydroxybenzophenone with less coloring can be obtained by separation and purification.

The polyhydroxybenzophenone thus obtained is 8. corresponding to the hydroxybenzoate used as a raw material. B, 4,4-tetrahydroxybenzophenone, 2.2,4.4'-tetrahydroxybenzophenone, 2°2', 5,5'-tetrahydroxybenzophenone, 2.2', 8.8', 4.4 -hexahydroxybenzophenone, 2,2'-dihydroxy-4,
4-dimethoxybenzophenone, 2.2-dihydroxy-4,4'-dioctoxybenzophenone, 2.2',
4.4'-tetrahydroxy-6,6-dimethylbenzophenone, 2.8.4.4-tetrahydroxybenzophenone, 2.2', 4°51-tetrahydroxybenzophenone, 2,8,4', Examples include 5-tetrahydroxybenzophenone.

〔Effect of the invention〕

According to the method of the present invention described in detail above, polyhydroxybenzophenone with little coloring can be produced from hydroxybenzoate in a high yield of 90% or more.

Hydroxybenzoate is obtained from hydroxy/L/'C in a yield of about 70-80%, and the yield of polyhydroxybenzophenone based on hydroxylbenzene is about 6%.
It is 0-80%.

It is possible to produce polyhydroxybenzophenone with a higher yield and less coloring than the corresponding yield of about 85 to 40% in the conventionally known method, and its industrial value is extremely large).

〔Example〕

The method of the present invention will be explained below with reference to Examples, but the method of the present invention is not limited to these Examples.

Example 1 8-hydroxyphenyl-2,4-dihydroxybenzoate 24.65', nitrobenzene 800P, zirconium chloride 12. (H' was charged into eight 500cc flasks, replaced with N2, and then heated to 70°C. Heat treated at 70°C for 4 hours, and then aged for 4 hours. After cooling, the reaction solution was analyzed by high performance liquid chromatography. As a result, 99% of the hydroxybenzoate was converted, and 2.2.4.4
94% yield of '-tetrahydroxybenzophenone (
(based on hydroxybenzoate).

Example 2 Nitrobenzene I Kf, Resorcinol 110? 2 I
Pour the mixture into a four-bottom flask, replace the inside of the flask with N2, raise the temperature to 100°C, and heat the phosgene to 995F 1.
Bubbling was carried out with stirring over a period of 0 hours. As the phosgene is blown in, the color of the reaction solution changes from light brown to blackish brown, and during the phosgene blowing, the color of the reaction liquid changes from pale brown to blackish brown. Gas generation was observed. After cooling the reaction solution to room temperature, the reaction solution was analyzed using high-performance liquid chromatography, and it was found that hydroxybenzoate was produced at a yield of 80% based on resorcinol.) Next, 54% of zinc chloride was added to the reaction solution. .5) After charging and raising the temperature to 70°C, heat treatment was performed at 70°C for 2 hours. After the heat treatment, the reaction product is cooled with water, and the water is heated to 700? Add dropwise and stir
After standing for 1 hour, the reaction product was washed with water to obtain a 150P wet cake. The wet cake was dissolved in 2 to 4 hot water, cooled and crystallized, and dried to the desired 2°2'
+4*4'ytrahydroxybenzophenone'4L90
．． Of was obtained (yield 78%m, p196-199
C) At this time, the conversion rate of resorcin was 86%, and the amount of unconverted hydroxybenzoate was 6% (based on resorcin).

Example 8 Nitrobenzene IK4 resorcinol 1105' was charged into a fourth flask of 21 mm, and the inside of the flask was replaced with N2.
The temperature was raised to 00°C, and phosgene 995' was blown in with stirring over 10 hours, followed by aging at 100°C for 4 hours. After the reaction is completed, the reaction solution is cooled to room temperature, and zinc chloride 68? After charging, the temperature was raised to 70℃, and HC/gas was
Heat treatment was carried out at 70° C. for 4 hours while blowing with l. After the heat treatment, the reaction product is cooled with water, and the water is heated to 700? After dropping the mixture and leaving it for 1 hour with stirring, the reaction product was washed with water and washed with water for 1 hour.
621 wet cake was obtained. 2K wet cake
f was dissolved in hot water, crystallized by cooling from the hot water, and dried to obtain 2.2',4,4-tetrahydroxybenzophenone 9.
8.4P was obtained (yield 80%). At this time, the conversion rate of resorcinol was 89%, and the amount of unconverted hydroxybenzoate was 1% or less.

Actual bj Examples 4 to 7, Comparative Examples 1 to 5 Instead of zinc chloride used in the second reaction in Example 1,
The reaction was carried out in the same manner as in Example 1 except that another metal chloride was used (the metal chloride was 0.6 times the mole of resorcinol).

Table - (]) THB: 2.2', 4.4'-tetrahydroxybenzophenone Example 8 Resorcin and zinc chloride (on the contrary, 8.5-h, yau)) p x: / iron chloride , □Except No, Example 2
The reaction was carried out in the same manner. 2, 2.4 obtained by isolation
．． 4-tetrahydroxy-6,6'-dimethylbenzo7
z/:/(''-P 198°C) was 269-, and the yield was 51%.

Claims (1)

[Claims] 1) General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (R represents an alkyl group, an alkoxy group, a halogen atom, and R is 2 or more (n≧2 and/or q≧2
), the substituents may be the same or different. m and p are integers of 1 to 5, n and q are integers of 0 or 1 to 4, and m+n≦5 and p+q≦5. ) is subjected to Fries rearrangement using at least one selected from zirconium halide, iron halide, zinc halide, tin halide, and bismuth halide as a catalyst, and the general formula ▲mathematical formula, chemical formula, There are tables etc. ▼ (R, m, n, p, q and m+n, p+q are the same as the above definitions.) Method for producing polyhydroxybenzophenone represented by the following. 2) Polyhydroxybenzophenone according to claim 1, characterized in that the product is 2,2',4,4'-tetrahydroxybenzophenone represented by ▲ which has a numerical formula, chemical formula, table, etc. ▼ manufacturing method.