Recent progress of halogen-dance reactions in heterocycles

摘要

This paper summarizes recent progress of halogen-dance reactions and its applications in heterocycles.Halogen-dance (HD) reactions,also referred to as halogen scrambling,halogen migration or based-catalyzed halogen dance (BCHD),was first found by chance in 1953.Since then researchers have been extensively studying this rearrangement.Their endeavors are reciprocated by following achievements:(1) significant extension of its scope;(2) illustration of its mechanism;(3) extensive applications in building novel or complicated compounds.These have been summarized in three reviews among which the most recent review was published in 1996.This review gives a summury of halogen dance reactions after 1996.We focus on the migrations in heterocycles including pyridines,quinolines,thiazoles and pyrazoles.