Synthesis of the reagent [Na][Pt(PEt3)(2)(eta(5)-7-CB10H11)] and preparation of the platinacarborane complexes [PtX(PEt3)(2)(eta(5)-7-CB10H11)] (X=H, Au(PPh3), Cu(PPh3), HgPh)

The salt [Na][Pt(PEt3)(2)(eta(5)-7-CB10H11)] (la) has been prepared. Protonation affords the hydride complex [PtH-(PEt3)(2)(eta(5)-7-CB H-10(11))] (2) while reactions with [AuCl(PPh3)], [CuCl(PPh3)](4), and [HgClPh] yield the dimetal compounds [PtM(PEt3)(2)(PPh3)(eta(5)-7-CB10H11)] (3a, M = Au; 3b, M = Cu) and [PtHgPh(PEt3)(2)(eta(5)-7-CB10H11)] (3c), respectively. The salt [N(PPh3)(2)][Pt(Co)(PPh3)(eta(5)-7-CB10H11)] (4) has also been obtained. Single-crystal X-ray diffraction studies have been made on 2 and 3a-c. Complexes 2, 3a, and 3c have similar molecular structures with H, Au(PPh3), and HgPh groups, respectively, sigma-bonded to the Pt of the Pt(PEt3)(2)(eta(5)-7-CB10H11) group. In 3b, however, the copper atom of the Cu(PPh3) moiety is attached to the Pt(PEt3)(2)(eta(5)-7-CB10H11) fragment both by a Pt-Cu sigma-bond and by two exopolyhedral B-H -->-Cu donor bonds from BH groups in the open face of the nido-7-CB10H11 cage ligating the platinum. The structure of the salt 4 has also been determined by X-ray diffraction.