Benzoxazine ring opening reaction with bifunctional nucleophile

摘要

The ring opening polymerisation of benzoxazines is postulated to proceed via heterolytic scission of the N,0-acetal moiety into a zwitterionic intermediate bearing an iminium cation and a phenoxide anion. Various reactions have been put forward as providing evidence for this mechanism. Ring opening addition reactions of benzoxazines with nucleophiles, probably via the proposed iminium cation, may be useful for preparing new polymers.