Metal complexes of sulphur ligands. Part 11. Reactions of platinum(II) and palladium(II) dithiocarbonates with dithiocarbonate ions

Abstract

Reaction of the complexes [Pt(S2COR)2] with K[S2COR](R = Et or Pri) followed by addition of [AsPh4]Cl generates [AsPh4][Pt(S2COR)3]. Variable-temperature 1H n.m.r. studies indicate rapid unidentate–bidentate exchange at ambient temperature. Attempted recrystallisation from CH2Cl2 or CDCl3, results in an intramolecular rearrangement to give [AsPh4][Pt(S2CO)(S2COR)]. Reaction of [Pd(S2COEt)2] with K[S2COEt] and [AsPh4]Cl gives [AsPh44][Pd(S2CO)(S2COEt)] as the main product. Reaction of [Pt(S2COR)2] with K[S2COR](R = Me, or CH2Ph) and [AsPh4]Cl generates [AsPh4][Pt(S2CO)(S2COMe)] or [AsPh4]2[Pt(S2CO)2], both of which give [PtL2(S2CO)] on addition of various Lewis bases L (L = PPh3, PMe2Ph, or ½Ph2PC2H4PPh2). The salt [AsPh4]-[Pt(S2COEt)3] is shown by X-ray diffraction analysis to have square-planar stereochemistry with one bi- and two uni-dentate [S2COEt]– groups. The crystals are monoclinic, space group P21/c with a= 9.95, b= 14.26, c= 25.82 Å, β= 99.3°.