Ruthenium-catalyzed meta-difluoromethylation of arene phosphines enabled by 1,3-dione

A highly efficient, meta-selective difluoromethylation of arene phosphines has been developed with ruthenium catalysis using 1,3-dione as an effective ligand. A wide variety of biarylphosphines bearing various functional groups were all compatible with the reaction conditions, leading to meta-difluoromethylated phosphine products in moderate to good yields.