Reaction of azides with dichloroindium hydride: Very mild production of amines and pyrrolidin-2-imines through possible indium-aminyl radicals

Organic azides are easily reduced to the corresponding amines by reaction with dichloroindium hydride under very mild conditions and in a highly chemoselective fashion. gamma-Azidonitriles give rise to outstanding five-membered cyclizations affording pyrrolidin-2-imines. A rationalization of the overall experimental data cannot exclude the occurrence of competitive radical and nonradical pathways, but certain results are, however, soundly consistent with the intermediacy of indium-bound nitrogen-centered radicals.