UNPRECEDENTED COORDINATION MODE OF THE TETRATHIO-MOLYBDATE OR TETRATHIO-TUNGSTATE ANIONS IN HETEROMETALLIC GOLD COMPLEXES - CRYSTAL-STRUCTURES OF [MOS4(AUASPH(3))(2)] AND [WS4(AUCH(2)PPH(3))(2)]CENTER-DOT-CH2CL2

Treatment of the tetrathiometalates [NH4](2)[MS(4)] (M = Mo or W) with [AuCl(AsPh(3))] (molar ratio 1:2) gave the trinuclear species [MS(4)( AuAsPh(3))(2)] (M = Mo 1 or W 2). Stepwise substitution of the arsine ligand afforded the complexes [MS(4)(AuAsPh(3))(AuPPh(3))] (M = Mo 3 o r W 4) or [MS(4)(AuPPh(3))(AuPPh(2)Me)] (M = Mo 5 or W 6). The reactio n with gold(I) complexes [AuCl(ylide)] follows a different pathway dep ending on the ylide ligand; with the less sterically demanding CH(2)PP h(2)Me the species [MS(4)(AuCH(2)PPh(2)Me)(2)] (M = Mo 7 or W 8) with three-co-ordinate gold were formed,but the ylide CH(2)PPh(3) led to [M S(4)(AuCH(2)PPh(3))(2)] (M = Mo 9 or W 10) with one three- and one two -co-ordinate gold centre. The crystal structures of complexes 1 and 10 were determined by X-ray diffraction.