Photoinduced carbamoylation of ethereal C–H bonds using pentafluorophenyl isocyanate

An intermolecular carbamoylation of ethers has been achieved via photoinduced functionalization of ethereal C–H bonds in the presence of benzophenone at ambient temperature. The carbamoyl group, a one-carbon unit with a high oxidation state, derived from pentafluorophenyl isocyanate (C6F5NCO) is chemoselectively introduced at the position geminal to the oxygen functionality in a single step. The present reaction system effectively activates the tertiary C–H bond at the sterically hindered site of fused bicyclic systems, and enables introduction of the carbamoyl group, which is then available for further synthetic elaborations.