An efficient and one-pot reductive cyclization for synthesis of 2-substituted benzimidazoles from o-nitroaniline under microwave conditions

A versatile and high yielding procedure for the direct generation of 2-substituted benzimidazoles from o-nitroaniline and aryl aldehydes in the presence of sodium dithionite as reducing agent under microwave irradiation is described. The obtained products were confirmed by physical and spectroscopic data such as IR, 1H NMR and 13C NMR. This procedure has a lot of advantages including; excellent yields of products, short reaction times, mild reaction conditions, easy work-up and other noteworthy advantages which make this method a valid contribution to the existing methodologies.