Method for preparing 2, 4-dichloroacetophenone

Abstract

The invention discloses a method for producing 2, 4-dichloroacetophenone. The method mainly includes acylation, hydrolysis, washing, distillation and crystallization, and m-dichlorobenzene and acetic anhydride are in acylation reaction under the effects of anhydrous aluminum trichloride. The method has the advantages that the m-dichlorobenzene is used as a raw material, the acetic anhydride is used as an acylating agent, A1C13 is used as a catalyst to prepare the 2, 4-dichloroacetophenone by means of reaction, and yield of obtained products is higher than that of products prepared by using acetyl chloride as an acylating agent; as the acetic anhydride is used as the acylating agent, the A1C13 is used as the catalyst and the m-dichlorobenzene which is extracted from chlorinated aromatics waste is comprehensively used as the raw material to prepare the 2, 4-dichloroacetophenone, by-products in a benzene chlorination process are disposed, reusing rate of chlorinated aromatics is increased, and the method has high economical and economical benefits.

Description

technical field

[0001] The main task of the present invention is to provide a production method of 2,4-dichloroacetophenone, specifically a method for producing 2,4-dichloroacetophenone by using chlorinated aromatic waste as raw material acetic anhydride as an acylating agent Methods. Background technique

[0002] 2,4-Dichloroacetophenone is the raw material for the preparation of ω-bromo-2,4-dichloroacetophenone or ω-2,4-trichloroacetophenone, the latter two are used for the preparation of imazalil and propane It is the intermediate of fungicides such as azole and etoconazole, and it is also the intermediate of insecticide chlorpyramid and herbicide wild swallow. m-dichlorobenzene is the main raw material for the synthesis of 2,4-dichloroacetophenone. Our company is an enterprise specializing in the treatment of chlorinated aromatic waste. Chlorinated aromatic waste is a common solid-liquid waste in petrochemical production, which contains a small amount of chlorobenzene,...

Examples

Embodiment Construction

[0011] Add 1.0mol m-dichlorobenzene and 1.3mol anhydrous aluminum trichloride to the reaction kettle, slowly add 1.0mol acetic anhydride dropwise under stirring, the temperature of the reaction solution is kept at 45°C-55°C during the dropwise addition, and the dropwise Heat up to 90~95°C at a rate of 1°C / min, reflux and stir for about 3 hours. After the reaction, add 200ml of 10% hydrochloric acid to the reaction solution and hydrolyze at 80°C. Leave it to cool and separate layers, separate the organic layer, drop Add it to a washing kettle with 200ml of water and wash it with water at 50°C. After standing and stratifying, the product is distilled under reduced pressure at 120-140°C, and the fraction before 135°C is collected, cooled and crystallized to obtain a white crystal with a purity of more than 99%. 4-Dichloroacetophenone.

technical field

[0001] The main task of the present invention is to provide a production method of 2,4-dichloroacetophenone, specifically a method for producing 2,4-dichloroacetophenone by using chlorinated aromatic waste as raw material acetic anhydride as an acylating agent Methods. Background technique

[0002] 2,4-Dichloroacetophenone is the raw material for the preparation of ω-bromo-2,4-dichloroacetophenone or ω-2,4-trichloroacetophenone, the latter two are used for the preparation of imazalil and propane It is the intermediate of fungicides such as azole and etoconazole, and it is also the intermediate of insecticide chlorpyramid and herbicide wild swallow. m-dichlorobenzene is the main raw material for the synthesis of 2,4-dichloroacetophenone. Our company is an enterprise specializing in the treatment of chlorinated aromatic waste. Chlorinated aromatic waste is a common solid-liquid waste in petrochemical production, which contains a small amount of chlorobenzene,...

Examples

Embodiment Construction

[0011] Add 1.0mol m-dichlorobenzene and 1.3mol anhydrous aluminum trichloride to the reaction kettle, slowly add 1.0mol acetic anhydride dropwise under stirring, the temperature of the reaction solution is kept at 45°C-55°C during the dropwise addition, and the dropwise Heat up to 90~95°C at a rate of 1°C / min, reflux and stir for about 3 hours. After the reaction, add 200ml of 10% hydrochloric acid to the reaction solution and hydrolyze at 80°C. Leave it to cool and separate layers, separate the organic layer, drop Add it to a washing kettle with 200ml of water and wash it with water at 50°C. After standing and stratifying, the product is distilled under reduced pressure at 120-140°C, and the fraction before 135°C is collected, cooled and crystallized to obtain a white crystal with a purity of more than 99%. 4-Dichloroacetophenone.