Solvent-free synthesis of 6-arylbenzimidazo[1,2-c]quinazolines under microwave irradiation

Abstract

The syntheses of 2-(2-nitrophenyl)-1-benzoyl-1H-benzimidazole derivatives 5-9 and their reduction to the corresponding 2-benzimidazoylbenzamides 10-13 are described. Compounds 10-13 were cleanly and efficiently converted to the corresponding 6-arylbenzimidazo[1,2-c]quinazolines 17-20 by microwave activation using SiO2-MnO2 as solid inorganic support.