Bimetallic Carbonyl Complexes Based on Iridium and Rhodium: Useful Tools for Hydrodefluorination Reactions

A set of bimetallic complexes based on iridium and rhodium with bis(diphenylphosphino)methane, bis(di‐iso‐propylphosphino)methane, diphenyl‐2‐pyridylphosphine and 2‐(di‐iso‐propylphosphino)imidazole bridging ligands was prepared. The complexes were characterized by NMR and IR spectroscopy and studied quantum‐chemically using DFT methods. The bimetallic systems succeeded in catalytic hydrodefluorination reactions of lower fluorinated aryl fluorides using molecular hydrogen and sodium tert‐butoxide as a base. Effects of (i) ligand variation, (ii) mono‐ vs bimetallic nuclearity, and (iii) Ir vs Rh metal identity were studied and rationalized en route to achieve an effective hydrodefluorination. Various bimetallic carbonyl complexes based on iridium and rhodium were characterized and used in the catalytic hydrodefluorination of aryl C−F bonds with dihydrogen as reductant.