Iron-catalyzed fragmentation-alkynylation, -alkenylation and -alkylation cascade enabled by photoinduced ligand-to-metal charge transfer

A fragmentation-alkynylation, -alkenylation and -alkylation cascade via photoinduced iron-catalyzed ligand-to-metal charge transfer (LMCT) is described. This reaction enables the preparation of a series of valuable internal alkynes and olefins, demonstrating a new synthetic pathway for the activation of iminyl radicals from oxime acids. This method exhibits a lot of advantages, including mild conditions, simple operation, and the use of cheap and easy-to-obtain iron catalysts.