Double carbonylation of substituted benzyl chlorides with cobalt carbonyl anion by phase transfer catalysis to give arylpyruvic acids

Abstract

When the phase transfer catalysis technique is used to carbonylate benzyl chlorides with the Co(CO)₄ ^– anion, a double carbonylation, giving arylpyruvic acids, is observed besides the expected monocarbonylation giving arylacetic acids; this reaction strongly depends on the electronic effects of the substituents on the aromatic ring.