Synthesis of benzimidazoles by copper-catalyzed aerobic oxidative domino reaction of 1,2-diaminoarenes and arylmethyl halides

Abstract

Arylmethyl halides are readily synthesized via halogenation from the basic raw materials, even in green processes. They are used to replace their downstream products to prepare medicinally important 2-aryl benzimidazoles. CuBr-catalyzed synthesis of 2-aryl benzimidazoles from arylmethyl halides and 1,2-diaminoarenes via a one-pot domino reaction is developed. This new synthetic method is simple, practical and cost saving, and tolerates wide functional groups. A mechanism of CuBr-catalyzed aerobic oxidative domino reaction via a one-pot four-step process is proposed. © 2013 John Wiley & Sons, Ltd.