Method of synthesizing 1, 3-dichloroacetone with catalysis of silicon dioxide-carried phosphotungstic heteropoly acid

Abstract

The invention discloses a method for catalytically synthesizing 1,3-dichloroacetone supported by silica-supported phosphotungstic heteropolyacid, which comprises the following steps: (1) dissolving sodium tungstate dihydrate in water, and injecting into the system under stirring Phosphoric acid was added dropwise in the water, and then refluxed after the dropwise addition; (2) Natural cooling and crystallization, redissolving the crystals in water at 80°C, then adding ether for extraction, recrystallizing in water, and obtaining phosphotungstic heteropoly acid; (3) Tetraethyl orthosilicate, deionized water, absolute ethanol, and phosphotungstic heteropolyacid are mixed and stirred to form a gel, then left to stand for aging and dried to obtain silica-loaded phosphotungstic heteropoly Acid catalyst; (4) Mix 1,3-dichloropropanol with hydrogen peroxide solution, add silica-supported phosphotungstic heteropolyacid catalyst, react at constant temperature for 10 hours, filter, and the filtrate is 1,3-dichloroacetone . The method provided by the invention has the advantages of simple operation, less environmental pollution, high yield and good purity of 1,3-dichloroacetone.

Description

Technical field

[0001] The invention belongs to a preparation method of 1,3-dichloroacetone, and specifically relates to a method for catalyzing the synthesis of 1,3-dichloroacetone by silica-supported phosphotungstic heteropoly acid. Background technique

[0002] 1,3-Dichloroacetone has two active functional groups, carbonyl group and halogen atom, and is an important reaction intermediate in the chemical and pharmaceutical industries.

[0003] At present, the synthesis methods of 1,3-dichloroacetone are as follows: (1) Direct substitution reaction of acetone with chlorine gas is used. This method is not easy to control the reaction rate, and large amounts of 1,1-dichloroacetone and 1,1,3- Trichloroacetone is difficult to separate and severely corrodes the equipment; (2) 1,3-Dichloropropanol is used as raw material to prepare 1,3-chloride by the oxidation method of chromium trioxide-sulfuric acid or sodium dichromate-concentrated sulfuric acid Acetone, the yield of this method is...