Base-catalyzed Hydrogen Deuterium Exchange at the α-Carbon of Ethyl Cinnamate and Certain Related Compounds

Deuterafions of ethyl cinnamate, ethyl BETA -phenylcinnamate, chalcone, and trans-cinnamonitrile were effected with deuterioethanol by means of a catalytic amount of sodium ethoxide. The first three reactions were shown to involve replacement of the alpha -vinyl hydrogen by deuterium, and the last was assumed to occur similarly. trans-Cinnamonitrile afforded a mixture of the cis and trans isomers. Two possible mechanisms are considered.