A photoredox-catalyzed trifluoromethylation/cyclization of N-allylbenzimidazoles using eosin Y-Na₂ under visible light affords trifluoromethylated benzimidazo-fused heterocycles. Two complementary protocols are established: Method A employs Togni's II under nitrogen-the first example of...
Kuang et al. (Wed,) studied this question.