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

摘要

A regiospecific synthesis of ortho-trifluoromethvlated 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.