Dehydrogenation of unsymmetric hydrazo compounds in ionic liquid: Novel green synthesis of azo compounds

摘要

Using NBS (N-bromosuccinimide) and the ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) as an oxidation system, twelve unsymmetric azo compounds were efficiently prepared from hydrazo compounds for the first time. In contrast to the known methods, this novel access to azo compounds presented here is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the solvent and the basic catalyst used can be recovered conveniently and reused efficiently.