Copper-Catalyzed Aerobic C-H Trifluoromethylation of Phenanthrolines.

Direct C-H trifluoromethylation of heterocycles is a valuable transformation. In particular, nonprecious metal-catalyzed C-H trifluoromethylation processes, which do not proceed through CF3 radical species, have been less developed. In this cluster report, a new copper-catalyzed aerobic C-H trifluoromethylation of phenanthrolines is described. This transformation affords trifluoromethylated phenanthrolines that have not been synthesized and preliminary mechanistic studies suggest that the CF3 group transfer may occur through cooperative activation.