Published on March 2018 | Organic Synthesis
One-pot simpler multistep reactions involving a new synthetic greener route and novel, efficient, reusable, cheaper and eco-friendly catalytic procedure have been discovered for the synthesis of variously substituted benzimidazole. The reaction of 1,2 diamine and substituted aldehyde in dichloromethane under ultrasonic irradiation at ambient temperature using Cu-doped ZnO furnish the expected product in excellent yield (87-98 %) in considerably reduced time (15-30 min). Spectral data and Physical constant confirmed the formation of the preferred product. Synthesized substituted benzimidazoles were also screened for antimicrobial activity and found significantly active against various gram positive and gram negative bacteria and some fungus. The main advantages of this research are mild reaction conditions, short reaction times, high yield, greener route, cheap, inexpensive, non-toxicity, and reusability of the catalyst.