Process for the preparation of acyl cyanides

摘要

Acyl cyanides of the general formula <IMAGE> in which R represents alkyl or substituted alkyl of from 1 to 8 carbon atoms; cycloalkyl or substituted cycloalkyl with 3 to 12 carbon atoms; aryl or substituted aryl; or an optionally substituted 5-membered or 6-membered heterocyclic radical which can additionally also be fused with a benzene ring, are prepared by reacting the corresponding carboxylic acid anhydride with an alkali metal cyanide or anhydrous hydrocyanic acid, at a temperature of between 50 DEG and 250 DEG C. and the resulting acyl cyanide is removed from the reaction medium by distillation, immediately after it has been formed.