Cluster synthesis. 8. Synthesis and crystal and molecular structures of the sulfido-bridged platinum osmium carbonyl cluster compounds PtOs3(CO)9L(PPh3)(μ3-S) 2 (L = CO, PPh3)

Abstract

The sulfido-bridged platinum osmium carbonyl cluster compounds PtOs3(CO)9L(PPh3)(μ3-S) 2 (2, L = CO; 3, L = PPh3) have been obtained in yields of 34% and 24%, respectively, from the reaction of Os3(CO)9(μ3-S)2 (1) with Pt(PPh3)2C2H4 under a nitrogen atmosphere. From the same reaction under a CO atmosphere the yield of 2 is increased to 76% while the yield of 3 is decreased to 3%. Both 2 and 3 have been characterized by single-crystal X-ray diffraction analysis. Crystal data for 2: space group P1, a = 8.944 (2) Å, b = 11.312 (2) Å, c = 17.058 (3) Å, α = 76.20 (2)°, β = 85.06 (2)°, γ = 78.41 (2)°, Z = 2, ρcalcd = 2.78 g/cm3. The structure was solved by the heavy-atom method and refined (3754 reflections) to the final values of the residuals RF = 0.032 and RwF = 0.037. Crystal data for 3: space group P21/n, a = 9.492 (3) Å, b = 31.220 (11) Å, c = 15.331 (4) Å, β = 99.34°, Z = 4, ρcalcd = 2.38 g/cm3. The structure of 3 was solved by direct methods and refined (3561 reflections) to the final values of the residuals RF = 0.038 and RwF = 0.038. Compound 3 is simply a PPh3 derivative of 2. Both compounds consist of triangular clusters of one platinum and two osmium atoms, with the third osmium atom linked to one of the osmium atoms in the triangular group via a metal-metal bond and the two triply bridging sulfido ligands. The formation of 2 and 3 is believed to occur by insertion of a PtL2 moiety into one of the Os-S bonds in 1 followed by ligand rearrangements. © 1984 American Chemical Society.