Sequential bromination-rearrangement of push-pull thiazolidines induced by pyridinium hydrobromide perbromide under homogenous reaction conditions

Abstract

Regiospecific bromination-rearrangement of the 5-substituted 2-alkylidene-4-oxothiazolidine derivatives induced by pyridinium hydrobromide perbromide (PHBP) provides a new synthetic approach to the corresponding push-pull thiazolidines with two exocyclic double bonds. In comparison to a heterogenous alternative, this conversion, taking place in acetonitrile under homogenous reaction conditions, has the advantage of almost quantitative yields and a substantial rate enhancement.