Ferrocenyl phosphane nickel carbonyls: Synthesis, solid state structure, and their use as catalysts in the oligomerization of ethylene

The synthesis of diverse ferrocenyl phosphane nickel carbonyls of type (FcPPh2)Ni(CO)3 (3), (FcPPh2)2Ni(CO)2 (4), fc(PR2Ni(CO)3)2 (R = Ph (6a), R = p-tolyl (6b)), and (fc(PPh2)2)Ni(CO)2 (7) (Fc = (η5-C5H5)(η5-C5H4)Fe, fc = (η5-C5H4)2Fe) starting from FcPPh2 (1), fc(PR2)2 (R = Ph (5a); R = p-tolyl (5b)), and Ni(CO)4 (2) is described. The structures of 3, 4, 6b, and 7 in the solid state are reported, intermolecular interactions by π–π-contacts are discussed. The behavior of 3, 4, 6a, 6b, and 7 towards the oligomerization of ethylene is reported. All compounds, except 4, were found to be inactive in homogeneous ethylene oligomerization, while they exhibit moderate activities (up to 660 kg prod/mol Ni h) in heterogeneous ethylene oligomerization experiments.