The preparation and structure of [Pt(S2N2){P(OR) nR′3-n}2] and [Pt(SeSN 2){P(OMe)nPh3-n] (n = 0-3)

Abstract

Dissolution of [S4N3]Cl in liquid ammonia produces a reactive solution which on treatment with cis [PtCl2(PR 3)2] gives [S2N2]2- complexes in 32-76% yields. Similarly, SeCl4 and [S4N 3]Cl in a ratio of 5:1 react cleanly with cis-[PtCl 2{P(OMe)n-Ph3-n}] to give the desired selenosulfur dinitrido, [SeSN2]2- complexes with no phosphorus containing starting material evident: by 31P NMR spectroscopy. The new complexes were characterised by IR, 31P NMR, microanalysis and X-ray crys tallography with nine crystal structures being reported. In 31P nmr the 1J PtP coupling constants are influenced by the oxygen content of their phosphorus ligands. In the mixed chalcogen complexes the Pt-N bond lengths appear to follow a simple trend as a consequence of the electronic properties of the phosphorus ligand and these trends can be interpreted empirically by examination of the LUMO but are not well supported by DFT calculations. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.