Catalytic Hydrogenolysis of Aryl C-F Bonds Using a Bimetallic Rhodium-Indium Complex.

A homogeneous rhodium-indium catalyst hydrodefluorinates substrates bearing strong aryl C-F bonds, including difluoro- and fluorobenzene, using 1 atm of H, alkoxide bases, and moderate temperatures (70-90 °C). Characterization of catalytic intermediates establishes a formal Rh/Rh redox cycle. The Rh → In interaction is proposed to enable catalysis by stabilizing the reactive Rh species, which is responsible for cleaving the Ar-F bond and is ultimately regenerated using H and base.