PhI(OAc)2-mediated synthesis of 6-(trifluoromethyl)phenanthridines by oxidative cyclization of 2-isocyanobiphenyls with CF3SiMe3 under metal-free conditions.

A mild and efficient method for the synthesis of 6-(trifluoromethyl)phenanthridines through oxidative cyclization of 2-isocyanobiphenyls with CF3SiMe3 under metal-free conditions was developed. The reaction allows the direct formation of C-CF3 bonds and rapid access to phenanthridine ring systems in one catalytic cycle.