Role of 1,4-dimethylpiperazine in radical cyclizations

Abstract

Radical cyclization of o-ethenyltrichloroacetanilides in boiling 1,4-dimethylpiperazine was examined with a comparison of the mode of radical cyclizations under a Bu3SnH-mediated condition. It was found that an attack of a hydrogen atom on the cyclized radical intermediates occurred more rapidly in 1,4-dimethylpiperazine than under the Bu3SnH-mediated condition. This phenomenon was also observed in similar reactions of N- ethenyltrichloroacetamide. ©ARKAT USA, Inc.