Electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides: selective synthesis of 8-methyleneazaspiro[4,5]trienes

Abstract

A novel and selective method for the synthesis of 8-methylenespiro[4,5]trienes via intramolecular electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides has been developed. In the presence of ICl or I 2, 8-methylene-1-azaspiro[4,5]trienes were selectively prepared from the electrophilic ipso-iodocyclization of N-(4-methylphenyl)propiolamides in moderate to good yields.