Visible-Light-Driven C–F Bond Cleavage in Perfluoroalkyl Carboxylic Acids: Readily Accessible Ruthenium-Bipyridine Complexes as Effective Catalysts

Herein, we report the reaction discovery and mechanistic studies of a visible-light-driven defluorination reaction of perfluoroalkyl carboxylic acids (PFCAs), a major class of perfluoroalkyl substances (PFAS) widely present in the environment that pose significant health and environmental concerns. The developed reaction employs 1–5 mol % of commercially available or readily accessible Ru-bipyridine complexes as the catalyst and achieves efficient C–F bond cleavage for C2–C8 PFCAs, perfluorinated dicarboxylic acids, and partially fluorinated carboxylic acids. Mechanistic studies suggest that the reaction proceeds via an inner-sphere pathway involving light-driven steps such as solvent-promoted ligand dissociation and Ru–O homolysis.