Fe/S-Catalyzed Synthesis of 2-Benzoylbenzoxazoles and 2-Quinolylbenzoxazoles via Redox Condensation of o-Nitrophenols with Acetophenones and Methylquinolines

International audienceFe/S catalyst generated in situ from FeCl2•4H2O and elemental sulfur S8 in the presence of a tertiary amine as a base was found to catalyze efficiently a 6eredox condensation of o-nitrophenols with acetophenones and methylquinolines. The condensed products 2benzoyl benzoxazoles and 2-quinolyl benzoxazoles were obtained in reasonable yields with water as the only byproduct at temperature as low as 80 °C