Prepn of percarboxylic acids

摘要

Anhydrous solns. of percarboxylic acids are prepd. simply and safely using 100% H2O2 by reacting H2O2 with the corresponding carboxylic acid in the presence of catalysts, in absolutely anhydrous soln. in an organic solvent which is either free from alcohol or cpds. forming alcohol with H2O2; or consists of a carboxylic acid ester and an amt. of an alcohol which pref. corresponds to the alcohol forming the ester, this amt. of alcohol corresponding to the amt. of ester consumed by the perhydrolysis water formed during reaction is removed azeotropically with the solvent used for the H2O2. The carboxylic acids are suitably acetic and propionic acids, the catalyst may be an inorganic acid, e.g. H2SO4, or an acid ion exchange resin, and the reaction is effected at 30-70 degrees C, pref. 50-60 degrees C in a solvent which is pref. an aliphatic ether alone or admixed with chloroform, or ethers of ethylene glycol or propylene glycol, or acetic acid.