Syntheses and structures of mixed-metal sulfido clusters containing incomplete cubane-type M2M′S4 and cubane-type M2M′2S4 cores (M = Mo, W; M′ = Rh, Ir)

The reactions of sulfido-bridged dimolybdenum and ditungsten complexes [M2S2(mu(2)-S)(2)(S2CNEt2)(2)] (1; M = Mo, W) with an equimolar amount of [M'Cl(PPh3)(3)] (M' = Rh, Ir) gave a series of mixed-metal incomplete cubane-type sulfide clusters [M'(PPh3)(2)(mu(3)-S)(mu 2-S)(3){M(S2CNEt2)}(2)(mu(2)-Cl)]. On the other hand, mixed-metal cubane-type sulfide clusters [{M'(cod)}(2){MCl(S2CNEt2)}(2)(mu(3)-S)(4)] (M' = Rh, Ir; cod = 1,5-cyclooctadiene) were obtained by the reactions of 1 with an equimolar amount of [M'Cl(cod)](2). Detailed structures of [Ir(PPh3)(2)(mu(3)-S)(mu(2)-S)(3){W(S2CNEt2)}2(mu(2)-Cl)]. 2CH(2)Cl(2) (3b . 2CH(2)Cl(2)) and [{Rh(cod)}(2){MoCl(S2CNEt2)}(2)(mu(3)-S)(4)]. 0.5CH(2)Cl(2) (4a . 0.5CH(2)Cl(2)) have been determined by X-ray crystallography. Compound 3b . 2CH(2)Cl(2) crystallized in the monoclinic system, space group P2(1)/n, With a 10.521(4) Angstrom, b = 32.325(5) Angstrom, c = 17.277(3) Angstrom, beta = 96.34(2)degrees, and Z = 4. Refinement by full-matrix least-squares techniques gave final residuals R = 0.071 and R-w = 0.068. Compound 4a . 0.5CH(2)Cl(2) crystallized in the monoclinic system, space group P2(1)/c, with a = 32.990(3) Angstrom, b = 10.847(4) Angstrom, c = 26.312(4) Angstrom, beta = 111.274(8)degrees, and Z = 8. Refinement by full-matrix least-squares techniques gave final residuals R = 0.037 and R-w = 0.048.