CLUSTER SYNTHESIS .39. NEW PLATINUM RUTHENIUM CARBONYL CLUSTER COMPLEXES WITH BRIDGING HYDRIDE LIGANDS - SYNTHESIS AND STRUCTURAL CHARACTERIZATIONS OF RU4PT(CO)13(COD)(MU-H)2, RU3PT(CO)9(MU-CO)(COD)(MU-H)2, RU4PT2(CO)11(COD)2(MU-3-H)2, AND RU5PT5(CO)18(COD)2(MU-H)2, COD = CYCLOOCTA-1,5-DIENE

The reaction of Ru4(CO)13(mu-H)2 (1) with Pt(COD)2 at 25-degrees-C yielded four new platinum-ruthenium carbonyl cluster complexes Ru4Pt(CO)13(COD)(mu-H)2 (2) (37%), Ru3Pt(CO)9(mu-CO)(COD)(mu-H)2 (3) (10%), Ru4Pt2(CO)11(COD)2(mu-3-H)2 (4) (2.5%), and Ru5Pt5(CO)18(COD)2(mu-3-H)2 (5) (1%). All compounds were characterized by IR, H-1 NMR, and single-crystal X-ray diffraction analyses. The cluster of compound 2 consists of a butterfly tetrahedron of four ruthenium atoms with one triangular face capped by a Pt(COD) grouping. Compound 3 consists of a cluster of three ruthenium atoms and one platinum atom in a tetrahedral arrangement. Compound 4 consists of a tetrahedral cluster of four ruthenium atoms with two of the triangular faces capped by Pt(COD) groupings. The other two triangular faces have triply bridging hydride ligands. In the cluster of compound 5, the five ruthenium and four of the platinum atoms are arranged in the form of a face-shared bioctahedron. The shared face consists of three of the platinum atoms. The fifth platinum atom is a cap on one of the Ru2Pt triangles. Two hydride ligands are believed to bridge metals of the triangular faces on the opposite ends of the bioctahedron. Compounds 1, 3, and 4 were obtained in low yields by heating 2 to 68-degrees-C. The yield of 3 was improved when 2 was heated to reflux in hexane solvent in the presence of Pt(COD)2, but the yield of 4 was not changed significantly. Compound 4 was also obtained in a low yield (10%) from the reaction of Ru4(CO)12(mu-H)4 With Pt(COD)2 in the presence of trimethylamine N-oxide. Crystal data: for 2 space group = P1BAR, a = 20.774 (3) angstrom, b = 15.364 (4) angstrom, c = 9.144 (1) angstrom, alpha = 95.60 (2)-degrees, beta = 102.68 (2)-degrees, gamma = 109.06 (3)-degrees, Z = 2, 3076 reflections, R = 0.019; for 3 space group = P1BAR, a = 9.427 (2) angstrom, b = 14.102 (2) angstrom, c = 9.423 (2) angstrom, alpha = 95.24 (2)-degrees, beta = 116.70 (1)-degrees, gamma = 87.72 (2)-degrees, Z = 2, 2180 reflections, R = 0.028; for 4 space group = P2(1)/c, a = 9.261 (2) angstrom, b = 21.362 (7) angstrom, c = 16.307 (4) angstrom, beta = 101.05 (2)-degrees, 2887 reflections, R = 0.024; for 5.C6H6 space group = P2(1), a = 12.338 (3) angstrom, b = 16.416 (4) angstrom, c = 12.792 (3) angstrom, beta = 116.18 (2)-degrees, 2801 reflections, R = 0.039.