Recent advances in FeCl3-photocatalyzed organic reactions via hydrogen-atom transfer

In recent years, FeCl3-photocatalyzed direct C–H/Si–H bond functionalization reactions have attracted huge attention. In those transformations, chlorine radical (Cl•) could be generated from FeCl3 via a ligand-to-metal charge transfer (LMCT)/homolysis process under light irradiation. The resulting chlorine radical subsequently acts as a hydrogen atom transfer (HAT) agent to abstract the hydrogen atom of aliphatic C–H, O–H, or Si–H bonds to give the corresponding C/Si/O-centered radicals for various organic transformations. In this review, we summarized the recent advances in the application of FeCl3 as a HAT photocatalyst for the C/Si–H functionalization to construct C–C, C–N, C–Si, C–S, C–B, and C-P bonds.