The syntheses and X-ray structure analyses of the heteronuclear monoanions [Os10C(CO)24Cu(NCMe)]– and [Os10C(CO)24Au(PPh3)]– as Their [PPh3Me]+ Salts

Abstract

The high nuclearity mixed-metal cluster monoanions [Os₁₀C(CO)₂₄Cu(NCMe)]^–(1) and [Os₁₀C(CO)₂₄Au(PPh₃)]^–(2) have been obtained by reaction of the carbido-dianion [Os₁₀C(CO)₂₄]^2–(3) with one equivalent of [Cu(NCMe)₄][BF₄] or Au(PPh₃)Cl, respectively, in CH₂Cl₂. Addition of excess [Cu(NCMe)₄][BF₄] to either (1) or (3) gives the di-copper species [Os₁₀C(CO)₂₄{Cu(NCMe)}₂](4). X-Ray analysis of the [PPh₃Me]⁺ salts of (1) and (2) show that the Cu and Au ligands have added to capping tetrahedra of the dianion (3) in µ₃- and µ-bridging positions, respectively. Crystals of [PPh₃Me][Os₁₀C(CO)₂₄Cu(NCMe)] are triclinic, space group P, with a= 16.452(3), b= 13.881(3), c= 13.290(3)Å, α= 82.1 2(3), β= 93.23(3), γ= 96.40(3)°, Z= 2; refinement of atomic parameters using 4 325 absorption corrected data converged at R 0.0492. The salt [PPh₃Me][Os₁₀C(CO)₂₄Au(PPh₃)] also crystallises in the triclinic space group P, with a= 17.296(4), b= 15.403(3), c= 15.191(3)Å, α= 107.31(3), β= 98.28(3), γ= 88.99(3)°, Z= 2; refinement of atomic co-ordinates using 5 314 absorption corrected data gave R 0.0551.