SULFIDES OF THE PLATINUM GROUP ELEMENTS .12. BIS(TETRAPHENYLPHOSPHONIUM) PENTAKAIDEKAKISSULPHIDO PLATINATES(IV)

Synthetic routes to tetraphenylphosphonium salts of [PtS(x)]2- are outlined, where x = 15 or 18. Generally, (PPh4)2[Pt(S5)3] is formed most readily. The compound [(C6H5)4P]2[PtS15], always solvated, has been obtained by synthesis in acetonitrile (sulphur, triethylamine, H2S and [PPh4]2[PtCl6]) and by metathesis (in DMF) from the known hydrated ammonium compound (NH4)2[Pt(S5)3]2H2O + 2[Ph4P]Br --> (Ph4P)2[Pt(S5)3].DMF + 2NH4Br, and from the dismutation (in acetone) 3PtS17(2-) --> PtS15(2-) + 2PtS18(2-). X-ray diffraction shows that crystals obtained from DMF and acetone are the solvated salts [Ph4P]2.[Pt(S5)3].S, with solvent molecules (S) uncoordinated. In both, the three platinopentathian rings related by a three-fold axis of the anion have the chair conformation. Molecules of the solvent are located between the anion and cation.