| Popis: |
The p-toluenesulphinatoplatinum(II) complexes, cis- and trans-[PtX(SO2tol)(PR3)2], [Pt2Cl2(SO2tol)2(PR3)2], [Pt2(SnCl3)2(SO2tol)2(PR3)2], [Pt2Cl3(SO2tol)(PR3)2], and [Pt2Cl(SnCl3)2(SO2tol)(PR3)2](X = Cl or Br; PR3= tertiary phosphine and tol =p-tolyl) have been prepared and their configurations assigned from 1H n.m.r. and i.r. spectral data. The latter shows that the sulphinato-group is attached to platinum through the sulphur atom, and has a similar trans-influence to that of the tertiary phosphines. This indicates a strong inductive release in the S–Pt σ-bond in contrast to previous suggestions that in the complexes of other metals the sulphinato-group is a weak σ-donor and a strong π-acceptor. In boiling toluene trans-[PtCl(SO2tol)(PMe2Ph)2] loses sulphur dioxide to form the complex trans-[PtCl(tol)(PMe2Ph)2]. In platinum(II) complexes the p-toluenesulphinate ion is even more weakly bridging than chloride ion. It takes up bridging positions, to give a solid product, only in association with SnCl3– in the complex [(PEt3)(SnCl3)Pt(SO2tol)2Pt(SnCl3)(PEt3)]. Its low affinity for the bridging position contrasts strongly with that of the diphenylphosphinate ion. |
