JPH02121945A - Production of benzophenones - Google Patents

Abstract

PURPOSE:To obtain the subject compound in high selectivity by carrying out dehydrohalogenative condensation reaction of an aromatic compound and a trilhalogenomethylbenzene compound in the presence of an acid catalyst using a crystalline aluminosilicate as a delhydrohalogenative condensation reaction catalyst and hydrolyzing the condensation product. CONSTITUTION:The objective benzophenone compound (e.g., 4,4'- dichlorobennzo-phenone) can be produced in high selectivity by carrying out dehydrolhalogenative condensation reaction of an aromatic compound and a trihalogenomethylbenzene compound in the presence of an acid catalyst using a crystalline aluminosilicate having an effective pore diameter of >=6Angstrom and a silica/alumina mol ar ratio of 4-200 (e.g., Y-zeolite, mordenite or beta-zeolite) as a dehydrohalogenative condensation reaction catalyst and hydrolyzing the obtained benzophenone dihalogenide. The process has various industrial merits such as easy separation of the product and the catalyst, reduced cost of waste acid treatment, reusability of catalyst, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing benzophenones, and more specifically, the present invention relates to a method for producing benzophenones, and more specifically, a dehydrohalogenation condensation reaction between an aromatic compound and trihalogenomethylbenzenes, followed by a hydrolysis reaction to produce benzophenones. The present invention relates to a method for producing benzophenones, which is characterized in that a crystalline aluminosilicate is used as a catalyst for the dehydrohalogenation condensation reaction.

(Prior art) Conventional methods for producing benzophenones include (1) a method in which an aromatic acid chloride and an aromatic hydrocarbon are subjected to a free sol fluoride reaction using a Lewis acid catalyst such as anhydrous aluminum chloride (S, J , Chard et al., J., Chem, S.
oc, 1952.376, etc.), (2) A method in which aromatic hydrocarbons and carbon tetrachloride are reacted in the presence of anhydrous aluminum chloride, and then hydrolyzed (Organic 5yn
thesis Co11 Vol, 1.95 (194
8) etc.), (3) A method for producing a 1.1-bis(4-halogenated phenol)-2,2-dichloroethylene compound by chromic acid oxidation (H, L, Bradlo et al., J, Am, Cbe++ , Soc, + 69 66
2<1947) etc.] are known. (4) As a special method, a method for producing dihydroxybenzophenone from dihydric phenol and pencitrichloride (Japanese Patent Application Laid-open No. 103555/1983, etc.) is known.

(Problem B to be solved by the invention) However, the above-mentioned methods (1) and (23) require at least an equimolar amount of anhydrous aluminum chloride to the acid chloride or aromatic hydrocarbon, and furthermore, aluminum chloride is recycled. It is difficult to use and difficult to process.(3)
This method also requires a large amount of chromic acid for the oxidation reaction and has problems with waste liquid treatment. (4) The reaction proceeds easily in the absence of catalysts with highly reactive dihydric phenols, giving dihydroxybenzophenone as the final product, but with unsubstituted benzenes, halogen-substituted benzenes, etc. There is little reaction at the bottom and it is not common.

(Means for Solving the Problems) As a result of intensive studies on a method for industrially advantageous production of benzophenones by solving the above-mentioned problems, the present inventors have discovered that aromatic compounds and trihalogenomethylbenzenes can be produced by In the method of performing dehydrohalogenation condensation reaction in the presence of an acid catalyst to form henzophenone dihalogenite and then hydrolyzing it to obtain benzophenones, high selectivity can be achieved by using crystalline aluminosilicate as the dehydrohalogenation condensation reaction catalyst. It has been found that pendufenonna can be produced at a similar rate.

Furthermore, the present invention also has the feature that when p-substituted pensitrichloride and monosubstituted benzene are used as raw materials, 4,4'-substituted benzophenone, which is particularly useful industrially, can be produced with high selectivity. .

The crystalline aluminosilicate used in the present invention preferably has an effective pore diameter of 6 Å or more, and a silica/alumina molar ratio of 4 or more and 200 or less. Representative examples of these aluminosilicates include Y zeolite, mordenite, β zeolite, ZSM-4, ZSM-
12, L-type zeolite, gmelinite, etc.

These crystalline aluminosilicates are used after being ion-exchanged with protons or polyvalent metal cations, and the proton-exchange type is particularly advantageously used. Furthermore, a metal component of group IB, group ①, group ①, or group ② may be contained. In particular, it is preferable to contain copper and silver.

Aromatic compounds used in the present invention include benzene and substituted benzenes, and specifically include benzene, alkylbenzenes such as toluene and xylene, halogenated benzenes such as chlorohenzene, fluorobenzene, dichlorobenzene, and difluorobenzene, etc. can be mentioned.

Examples of trihalogenomethylbenzenes include trihalogenomethylbenzene or nuclear-substituted trihalogenomethylbenzene, and examples of methyl-substituted halogens include chlorine, bromine, and the like. Specifically, pensitrichloride, benzotribromide, and their substituted products with halogen, alkyl, etc. can be mentioned. For example, p-
Chloropene cytrichloride, 0-chloropene cytrichloride, p-fluoropene cytrichloride, p-methylbenzochloride, 0-methylpene cytrichloride, 2,4-dichloropene cytrichloride and these trichlorides replaced with tribromide Substituted tribromides and the like can be mentioned.

The reaction conditions used in the present invention vary depending on the type of raw materials, but are generally 30 to 400°C, preferably 50 to 50°C.
The reaction temperature of C and the molar ratio of raw material aromatic compound/benzotribromide are 0.1 to 100, preferably 1 to 5.
The reaction pressure is usually atmospheric pressure, but reduced pressure or increased pressure conditions can also be used. Furthermore, it is preferable for the reaction to proceed by passing an inert gas such as nitrogen through the reaction system to remove the generated hydrogen halide from the system. If a large amount of water is present during the dehydrohalogenation condensation reaction, benzoic acids will be produced as by-products due to the hydrolysis of trichloride.
The water content in the system is preferably 1ooOppn+ or less, preferably 500 ppm or less.

The presence of a small amount of water also allows a dehydrohalogenation condensation reaction followed by a hydrolysis reaction to occur on the same catalyst, producing benzophenones in one step.

As a reaction method, any commonly used method can be used, such as a slurry method using a powdered catalyst or a fixed bed method using a shaped catalyst.

The hydrolysis step can be easily carried out using a conventional acid catalyst, but it can also be carried out using a crystalline aluminosilicate catalyst similar to the dehydrohalogenation condensation catalyst.

(Effects of the Invention) According to the method of the present invention, hensifenones can be produced with high selectivity and can be carried out using a solid catalyst without using a catalyst such as soluble aluminum chloride, making it easy to separate the product and the catalyst. , and the disposal of waste acid is also reduced. Furthermore, the catalyst can be used repeatedly by regeneration such as solvent regeneration, combustion regeneration, etc., which has extremely large industrial advantages.

Further, p-substituted penzotrihalogenide and monosubstituted benzene have the advantage that an industrially useful 4.4'-isomer can be obtained with high selectivity.

(Example) Hereinafter, the present invention will be specifically illustrated with reference to Examples, but the present invention is not limited thereto.

Example 1 Commercially available Y-type zeolite (Si(h/Al t(h
= 5.

3) was proton-exchanged according to a conventional method and used as a catalyst. Put 7.6 g of chlorobenzene and 9.2 g of p-chloropene citrichloride into a 50 ml three-bottle flask with a cooling tube, add 10 g of the above hydrogen type Y zeolite while stirring, and react with nitrogen gas at 0.4 Nl/hr. While being introduced into the system, the reaction was carried out by heating to 80°C in an oil bath. Generation of hydrogen chloride gas was observed as the reaction proceeded.

After reacting for 3 hours, 10 cc of water was added, the temperature was raised to 100°C, and the reaction was continued for 1 hour. As a result, the yield of 4.4"-dichlorobenzophenone was 16 mojl!χ, the yield of 2.4' dichlorobenzophenone was 0.3 molχ,
The 4.4-isomer selectivity in the produced hensifhenone was over 98%. However, the yield is approximately 1 g of trihalogenomethylbenzene. That is, the yield when trihalogenomethylhenzene is 100 mofχ is expressed as mobχ.

Example 2 Same as Example 1, but using U.S. Pat.
．． According to the method described in No. 308,069, a 10% aqueous solution of tetraethylammonium hydroxide 500
19.9 g of sodium aluminate was dissolved in 250 g of distilled water, and 19.9 g of sodium aluminate was mixed with stirring, and then 1 silica powder was added.
69g were mixed. This raw material mixture was placed in an In Teflon-coated autoclave and heated at 150°C for 2 hours.
Hydrothermal synthesis was carried out for 6 days under stirring at 00 rpm to obtain beta zeolite. This product was treated with 1N nitric acid at room temperature for about 4 hours, filtered, washed with water, dried, and reacted with hydrogen-type zeolite (sio1/Alzos = 65). As a result, the conversion rate of P-chloropene citrichloride before hydrolysis was 25%, and the yield of 4.4'-dichlorobenzophenone after hydrolysis was 24 moiχ.

Example 3 The reaction was carried out in the same manner as in Example 1, except that the reaction temperature was changed to 120°C. As a result, the yield of 4,4゛-dichlorobenzophenone was 41IIIof! It was χ.

Example 4 Using the same catalyst as in Example 1 and in the same manner as in Example 1,
2g of benzotrichloride and 20g of benzene with 4 catalysts
The reaction was carried out using g. As a result, the conversion rate of benzotrichloride was 23%, and the yield of benzophenone was 22wof.
! Met.

Example 5 Same as Example 1, except that commercially available mordenite (SiO□/3=15 to 8j22) was used as a catalyst, and 5 g of hydrogen-type mordenite was added to 2.4 g of P-chloropene citrichloride and 22 g of chlorobenzene. , 100°C
I reacted with The results after 5 hours of reaction time showed that the conversion rate of p-chloropene citrichloride was 10% and 4,4゛-
The yield of dichlorobenzophenone is 8 mo f! %Met.

Example 6 In the same manner as in Example 1, however, the hydrogen type Y zeolite of Example 1 was further copper-exchanged using an aqueous copper chloride solution to prepare a catalyst containing 1% by weight of copper and used for the reaction. did. The reaction was carried out for 4 hours at a reaction temperature of 80"C, and the result was 4.4'-
The yield of dichlorobenzophenone was 21 moffχ.

Example 7 Commercially available ultra-stable Y-type zeolite (sio, / A e 2
03-6, NazO/Alt(h -0, 01)
Using the same method as in Example 1, 4 g of the catalyst was added to 2.4 g of p-chloropene citrichloride and 22 g of chlorobenzene, and the mixture was reacted at 100°C for 2 hours. As a result, the conversion rate of p-chloropene citrichloride was 76%, and the yield of 4,4'-dichlorobenzophenone was 71 mo! ! , χ.

Example Day Same as Example 7, except that as a result of reaction at a reaction temperature of 60°C for 4 hours, the yield of 4,4′-dichlorobenzophenone was 73 toolχ, and the selectivity for the 4.4″ isomer was 9.
It was 8%.

Example 9 The reaction was carried out in the same manner as in Example 1, except that p-chloropene citrichloride was replaced with 0-chloropene citrichloride. As a result, the yield of 2.4°-dichlorobenzophenone was 81 IIoI! , χ, the yield of 4.4゛-dichlorohensiphenone is 0.4m.

It was βχ.

Example 10 The Y zeolite used in Example 1 was molded and arranged into 7 to 12 meshes, 10 g was filled into a U-shaped quartz tube of 10 ma + φ x 200 d, heated to 120 ° C. in an oil bath, and ρ-chloropene citrichloride/ Chlorobenzene = 1/20
The raw materials were supplied at a molar ratio of 2.5 cc/Hr and reacted. The moisture content in the raw material was 250p-. The reaction results showed that the conversion rate of p-chloropene citrichloride was 12%, 4
．． The yield of 4°-dichlorobenzophenone is l1mofχ
The selectivity for benzophenones was 96%.

Example 11 The same procedure as in Example 7 was carried out, except that 2.2 g of p-methylbensitrichloride and 20 g of toluene were used as raw materials, and the reaction was carried out at a reaction temperature of 90° C. for 2 hours, followed by hydrolysis. As a result, the conversion rate of p-methylbensitrichloride before hydrolysis was 55%, and 4.4" after hydrolysis.
The yield of -dimethylbenzophenone was 51 molχ.

1 other person

Claims (1)

[Claims] Crystalline aluminosilicate is used as a dehydrohalogenation condensation reaction catalyst when aromatic compounds and trihalogenomethylbenzenes are subjected to a dehydrohalogenation condensation reaction in the presence of an acid catalyst and then hydrolyzed to produce benzophenones. 1. A method for producing benzophenones, characterized by using them.