ELECTROCHEMISTRY OF COORDINATION COMPOUNDS. XX. ELECTROGENERATED Rh(CO)(PPh3)3 AND Ir(CO)(PPh3)3

Article abstract of DOI:10.1016/S0022-328X(00)98652-2

The redox behaviour of the d⁸ complexes ⁺ (M=Rh, Ir) was studied on platinum electrode in 1,2-dimethoxyethane by cyclic voltammetry, differential pulse voltammetry, and potentiostatic coulometry.The complexes show two reversible one-electron reductions consistent with the formation of the rare zerovalent M(CO)(PPh3)3 and the anionic ^- derivatives, respectively.The reduced species were characterized by ESR and IR spectroscopy.A significant feature is that the one-electron reduced intermediates, in spite of their radical nature, react very easily with molecules capable of reacting as proton rather than H-atom sources to give the hydride species HM(CO)(PPh3)3.A tentative interpretation of this behaviour is suggested.