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

Abstract

A set of bimetallic complexes based on iridium and rhodium with bis(diphenylphosphino)methane, bis(di-isopropylphosphino)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.

Cooperativity between metal centers in homobimetallic PdII–NHC complexes: catalytic potential towards hydrodefluorination

“…), leading to significant inorganic waste generation. 13 A more sustainable approach would be the use of H 2 gas (however, this poses significant safety risks) 14 as a reductant or a greener alcohol, e.g. isopropyl alcohol, as a hydrogen source.…”