Process for preparing 4,4'-dichlorodiphenyl sulfone

Abstract

The invention belongs to the field of organic synthesis, and particularly relates to a process for preparing 4,4'-dichlorodiphenyl sulfone. The process comprises the following steps of carrying out aFriedel-Crafts reaction on thionyl chloride and chlorobenzene under the action of a catalyst, carrying out cooling for hydrolyzing after the reaction is finished, then carrying out heating for dissolving, carrying out cooling to separate out crystals, carrying out filtering to obtain 4,4'-dichlorodiphenyl sulfoxide, then dissolving the 4,4'-dichlorodiphenyl sulfoxide in glacial acetic acid, addinghydrogen peroxide to carry out an oxidation reaction, carrying out cooling after the reaction is completed, and carrying out filtering to obtain the 4,4'-dichlorodiphenyl sulfone, wherein the catalyst is a mixture of anhydrous aluminum chloride and benzyl triethyl ammonium chloride. The process disclosed by the invention is simple, low in cost and less in impurity, the composite catalyst is adopted, and no additional solvent is added, so that purity of the obtained product is high, and the content of the obtained product is 99.4% or above. The yield reaches 92% or above, the economic benefitis good, and industrial production is facilitated.

Description

technical field [0001] The invention belongs to the field of organic synthesis, in particular to a process for preparing 4,4'-dichlorodiphenyl sulfone. Background technique [0002] 4,4'-Dichlorodiphenylsulfone (DDS) is an important organic synthesis product, the main raw material for the preparation of engineering plastics such as polysulfone and polyethersulfone, and an intermediate for medicine, dyes and pesticides. It can be used to prepare a variety of polymer products, such as resins such as bisphenol A polysulfone, polyphenylene ether sulfone, and polyamide sulfone, and can also be used to prepare 4,4'-diaminodiphenylsulfone, an intermediate of leprosy medicine. With the wide application of polymer materials, the demand for DDS is also increasing. [0003] There are many ways to produce DDS in industry, mainly including sulfuric acid method, chlorosulfonic acid method, sulfur trioxide method and sulfoxide oxidation method. The sulfuric acid method has low cost and s...

AI Technical Summary

Problems solved by technology

The sulfuric acid method has low cost and simple raw materials, but the conversion rate is low, the reaction time is long, the melting point of the product is low, and the quality is not good

The chlorosulfonic acid process is relatively mature, and the product quality is good, but the production cost is high and the three wastes are serious

The preparation of DDS by sulfur trioxide method is an improved method. It is reported that UCC Company of the United States adopts this method. It uses sulfur trioxide sulfonation and thionyl chloride acyl chloride route, and the process is relatively complicated.