Mild and Efficient Debromination of vic-Dibromides to Alkenes with NiCl2·6H2O/Indium System

The debromination of vic-dibromides to alkenes is impor-tant in organic synthesis as a double bond protection-deprotection strategy.1 Although reductive debromination of vic-dibromides with various agents has been the subject of many reports, some of these methods are associated with limitations regarding low yields, prolonged reaction times, and harsh reaction conditions.2 Consequently an efficient and mild procedure for debromination of vic-dibromides continues to be developed. The chemical reactivity of NiCl2/ M system (M = Zn, Al, Sm) has been the subject of consi-derable interest and the reducing ability of these systems has been extensively studied.3 Because of the close resemblance of indium to zinc in several respects, including first ioni-zation, we considered that NiCl2·6H2O/In system could also be a useful addition to the conventional method. Recently