Production of carboxylic acid halides and carboxylate salts

摘要

A process for preparing carboxylic acid halides and carboxylate salts by reacting metal or "onium" halides with carboxylic anhydrides, which process is very suitable for working-up anhydrous, spent catalyst preparations. The resulting carboxylic acid halide or carboxylate salt can be used as an acylating reagent or alkylating reagent, and metal halide or "onium" halide liberated during this can be reacted anew with carboxylic anhydride and regenerated, thereby making it possible to effect a hydrolysis-free alkylation or acylation without forming salt-type waste products. If the mixture of carboxylic acid halide and carboxylate salt is allowed to react with an alcohol, preferably in situ, the resulting ester can be isolated without hydrolysis.