Free radical reactions in solution. Part 4. Radical-initiated reduction of acid chlorides to alkanes by tri-n-propylsilane: removal of unwanted carboxy-groups from organic molecules

Abstract

Aliphatic acyl chlorides RCOCl react with tripropylsilane in the presence of t-butyl peroxide at 140–170° to give the corresponding alkane RH. Yields are good when R is a primary or secondary alkyl group, poor when R is tertiary or benzylic, and zero when R is phenyl. A radical chain reaction is postulated. The reaction should be synthetically useful for removing carboxy-groups from carboxylic acids RCO2H, where R is a primary or secondary alkyl group.