Halogenated boron-dipyrromethenes: synthesis, properties and applications.

Boron-dipyrromethene dyes (BODIPYs) containing halogens at pyrrole carbons are very useful synthons for the synthesis of a variety of BOIDPYs for a wide range of applications. Among the functional groups, halogens are the functional groups which can be regiospecifically introduced at any desired pyrrole carbon of the BODIPY framework by adopting appropriate synthetic strategies. The halogenated BODIPYs can undergo facile nucleophilic substitution reactions to prepare several interesting BODIPY based compounds. This review describes the synthesis, properties and potential applications of halogenated BODIPYs containing one to six halogens at the pyrrole carbons of the BODIPY core as well as properties and applications of some of the substituted BODIPYs derived from halogenated BODIPYs.