| Abstract: | On the coordination chemistry of phosphines and phosphinoxides. XXIII. Heavy metal complexes of tetramethyl-biphosphine The reactions of tetramethyl-biphosphine with salts of 3d elements including Cd and Hg, too, in THF, benzene, acetonitrile and alcohols, respectively, results in forming complexes of differing compositions: (MnXn)2{(CH3)2P? P(CH3}2)3? Mn = TiIII, VIII, CrIII, FeII, NiII, CuI; MX2{(CH3)2P? P(CH3)2}2? M = CoII, NiII, HgII; MX2 · (CH3)2P? P(CH3)2? M = FeII, NiII, Zn, Cd, HgII; X = Cl, Br, J. The partly intensively coloured complexes have low solubilities; this item complicates the performing of structure determining methods. Partial informations about the structures of the complexes are to be gained by magnetic and spectrophotometric measurements and X-ray investigations. The tendency of (CH3)2P? P(CH3)2 to form complexes with transition metals differs from that of other biphosphines. Splitting of the P? P bond due to metal salts does not occur. (CH3)2P? P(CH3)2 acts as a monodentate or bidentate ligand, like other members of the R2P? PR2 series do too. The forming of ligand bridges seems to be favoured in comparison to the chelate function. |
