Synthesis and characterisation of mono- and di-nuclear mixed phosphathia complexes of gold(I): Crystal structures of [Au(RSC(2)H(4)SR)]PF6, [Au(RSC(3)H(6)SR)]PF6 and [Au-2(RSC(2)H(4)SR)(2)]Cl-2 center dot 4CH(2)Cl(2) (R=Ph(2)PC(2)H(4))

Mononuclear gold(I) complexes of two linear P2S2 donor ligands, [AuL]PF6 [L = RSC(2)H(4)SR or RSC(3)H(6)SR (R = Ph(2)PC(2)H(4))] have been prepared by reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with L and TIPF6 in MeCN solution. The crystal structure of [Au(RSC(2)H(4)SR)](+) shows a primary P-2-donor set with additional long-range thioether interactions giving a distorted linear geometry around Au-1 in the solid state; Au-P 2.284(7), 2.302(7), Au ... S 2.899(6), 3.190(7) Angstrom. The structure of [Au(RSC(3)H(6)SR)](+) shows a very similar arrangement; Au-P 2.279(6), 2.287(6) Angstrom, Au ... S 3.097(5), 3.101(6) Angstrom. The non-conducting binuclear species [Au(2)Cl(2)L] were obtained by reaction of [AuCl(tht)] with L in a 2: 1 molar ratio in CH2Cl2 solution, while a 1.1 [AuCl(tht)]: RSC(2)H(4)SR ratio yielded the unusual species [Au-2(RSC(2)H(4)SR)(2)]Cl-2, the crystal structure of which shows a linear P-2-donor set at each Au, giving a helical cavity which contains a Cl- anion. All complexes have been characterised by IR, H-1 and P-31 NMR spectroscopies, FAB mass spectrometry and microanalyses.