REACTIONS OF UNSATURATED NICKEL-TUNGSTEN AND NICKEL-MOLYBDENUM COMPLEXES WITH ORGANIC DISULFIDES - SYNTHETIC AND STRUCTURAL STUDIES

The behavior of the unsaturated complex (eta-C5Me5)Ni-W(CO)3(eta-C5H4Me) (Ni-W, 1) toward selected chalcogenide-containing ligands is described. The Ni-W species is inert to Me2S under ambient reaction conditions, but disulfides and diselenides react with 1. Diphenyl disulfide, dimethyl disulfide, and diphenyl diselenide oxidatively add across the mixed-metal bond to afford (eta-CsMe5)Ni(mu-CO)(mu-ER)W(CO)(ER)(eta-C5H4Me) (Ni-W; ER = SPh, SMe, SePh), which contain bridging and terminal thiolate or selenate ligands. A similar Ni-Mo product was formed when (eta-CsMe5)Ni-MO(CO)3(eta-C5H4Me) was treated with PhS2Ph. In most cases the reactions are clean, but [(eta-C5Me5)Ni(mu-SePh)]2 was also isolated in the diphenyl diselenide reaction. All the complexes are fluxional on the NMR time scale. The bis(benzenethiolate) nickel-tungsten species was studied by VT H-1 NMR: some dynamic behavior was arrested at -80-degrees-C. Structures of (eta-C5Me5)Ni(mu-CO)(mu-SPh)W(CO)(SPh)(eta-C5H4Me) (Ni-W, 2a) and [(eta-C5Me5)Ni(mu-SePh)]2 (3) were ascertained by single-crystal X-ray diffraction studies. Crystal data for C30H32O2NiS2W (2a): monoclinic, P2(1)/c (No. 14), a = 15.101(1) angstrom, b = 11.531(2) angstrom, c = 17.262(2) angstrom, beta = 108.01(1)-degrees, Z = 4. Crystal data for C32H40Ni2Se2 (3): triclinic, P1BAR (No. 2), a = 8.444(4) angstrom, b = 9.495(3) angstrom, c = 10.851(6) angstrom, alpha = 112.64(3)-degrees, beta = 108.88(4)-degrees, gamma = 95.92(3)-degrees, Z = 1.