An improved environmentally benign procedure for the synthesis of various benzimidazole and benzoxazole derivatives using green solvent PEG 400 . We have optimized the reaction condition and it was found that PEG 400 was believed to be best as compared to PEG 200 , PEG 600 and PEG 800 at 80 to 85 °C. This method provides a novel route for the synthesis of benzimidazole and benzoxazole derivatives. The main attractive features of this process are a mild reaction conditions, easy workup procedure and good to excellent yield. The structures of all the synthesized compounds were confirmed by 1 H NMR, IR, MASS and Elemental Analysis.
Khunt, M. D., Kotadiya, V. C., Viradiya, D. J., Baria, B. H., & Bhoya, U. C. (2014). Easy, Simplistic and Green Synthesis of Various Benzimidazole and Benzoxazole Derivatives Using PEG400 as a Green Solvent. International Letters of Chemistry, Physics and Astronomy, 25, 61–68. https://doi.org/10.18052/www.scipress.com/ilcpa.25.61