Synthesis of the chiral tetrahedral clusters RCCo2NiCp(CO)4(bmf) (R = H, Ph) and thermally promoted diphosphine ligand activation: Regiospecific P-C bond scission and X-ray diffraction structure of Co2NiCp(CO)4[μ2,η2,η1-C(H)CC(PPh2)C(O)OCH(OMe)](μ-P

The tetrahedral clusters RCCo2NiCp(CO)6 (R = H, Ph) react with the chiral diphosphine ligand 3,4-bis(diphenylphosphino)-5-methoxy-2(5H)-furanone (bmf) to give the diphosphine-bridged clusters RCCo2NiCp(CO)4(bmf) as a mixture of diastereomers. Thermolysis of these products at 83 °C leads to complete decomposition of the phenyl-capped cluster and regioselective P-C bond cleavage in the hydrogen-capped cluster, as evidenced by the isolation and structural characterization of Co2NiCp(CO)4[μ2,η2,η1-C(H)CC(PPh2)C(O)OCH(OMe)](μ-PPh2).