Rosenmund Reduction

Abstract

The transformation of an acyl chloride into corresponding aldehyde by the hydrogenation in a toluene solution over barium sulfate‐supported palladium is generally referred to as the Rosenmund reduction. It has been reported that the reduction of unsaturated acyl chlorides in some cases result in the overreduction of double bonds. The study finds that the palladium catalyst is labile under reaction conditions, and the particle size and surface structure change quickly. Furthermore, some acyl chlorides do not undergo the Rosenmund reduction. This method has been replaced by the more reliable Brown hydroboration method. This reaction has been used for the preparation of aldehydes.