Synthesis of ortho-(Fluoro)alkylated Pyridines via Visible Light-Promoted Radical Isocyanide Insertion

A regiospecific synthesis of ortho‐trifluoromethylated and ortho‐(fluoro)alkylated pyridine derivatives has been developed. This strategy is enabled by visible light‐promoted vinyl isocyanide insertions with Umemoto’s reagent and electron‐deficient bromides at room temperature. The methodology presented here provides an access to highly functionalized ortho‐(fluoro)alkylated pyridine derivatives regiospecifically under mild conditions with good yields. The proposed mechanism was supported by TEMPO trapping experiments, Stern–Volmer analysis and light off/on and time profile experiments.