FeBr₂-Catalyzed Synthesis of Benzimidazoles from Aryl Azides

Significance

This reaction represents the first example of the iron-catalyzed C-H amination by using azides, formerly known only with Rh catalysis. 2-Azidoanilines are readily available from 2-nitroanilines. The reaction gives high yields with most aryl aldehydes, tolerates important functional groups and can be useful for modular synthesis of benzimidazoles.