Metal complexes of sulphur ligands. Part 12. Synthesis, characterisation, and reactions of palladium(II) and platinum(II) complexes of type [MX(PR′3)(S–S)](X = halide, S–S–=[S2PR2]–, [S2CNR2]–, or [S2COR]–)

Abstract

Reaction of [Pd(PR′₃)(S₂PPh₂)₂](PR′₃= PPh₃ or PMe₂Ph) with excess of AgX in acetone (X = Cl, Br, I, or SCN) leads to facile replacement of the unidentate [S₂PPh₂]^– group by X^– to give [PdX(PR′₃)(S₂PPh₂)]. Similar reactions with [Pt(PR′₃)(S–S)₂](S–S^–=[S₂PPh₂]^– or [S₂CNEt₂]^–) are not very efficient and a better general method of synthesising [MX(PR′₃)(S–S)] complexes (M = Pd or Pt: X = Cl, Br, or I; S–S^–=[S₂PMe₂]^–, [S₂CNEt₂]^–, [S₂CNPrⁱ₂]^–, or [S₂COEt]^–) is by reaction of equimolar amounts of [{MX₂(PR′₃)}₂] and alkali-metal dithioacid salts. The complexes [MX(PR′₃)(S–S)] have been characterised by elemental analyses and molecularweight, ¹H n.m.r., and i.r. measurements and some of their reactions have been investigated.