Electron transfer and chloride ligand dissociation in complexes [(C5Me5)ClM(bpy)]+/[(C5Me5)M(bpy)]n (M=Co, Rh, Ir;n = 2+, +, 0, −): A combined electrochemical and spectroscopic investigation

Autor: Wolfgang Kaim, Eberhard Waldho¨r, Jan Fiedler, Ralf Reinhardt
Rok vydání: 1996
Předmět:
Zdroj: Journal of Organometallic Chemistry. 524:195-202
ISSN: 0022-328X
Popis: In contrast to the rapid and chemically reversible two-electron ECE′ reductive elimination reaction[(C 5 Me 5 )ClM(bpy)] + + 2e − → (C 5 Me 5 )M(bpy)+Cl − ,M=Rh or Ir, the analogous cobalt system exhibits two separate one-electron steps (EC + E′ process) with a persistent, EPR-spectroscopically characterized cobalt(II) intermediate [(C 5 Me 5 )Co(bpy)] + . Within the series of coordinatively unsaturated homologous species (C 5 Me 5 )M(bpy), the cobalt derivative exhibits the smallest and the iridium homologue the largest metal(I)-to-bpy electron transfer in the ground state, as evident from electrochemical potentials and long-wavelength absorption data. A comparison within that homologous series indicates why the rhodium system, with its intermediate position, is most suitable for hydride transfer catalysis.
Databáze: OpenAIRE