Trinuclear gold(I) complexes with various coordination modes of N,N-dimethyldithiocarbamate

The compounds [Au-3(S2CNMe2)(3){mu(3)-(PPh2)(3)CH]} (1) and [Au-3(S2CNMe2) (mu-S2CNMe2){mu(3)-( PPh2)(3)CH}]ClO4 (2) are obtained by reaction of [Au3C l3 mu(3)-(PPh2)(3)CH}] with three equivalents of sodium dimethyldithiocarba mate or two equivalents of the same reagent in the presence of excess NaCLO 4. Reaction of 2 with the group 11 metal complexes [AuCl(tht)], CuCl or [Au (C6F5) (tht)] takes place with displacement of [M(S2CNMe2)](n) (M=Cu, Au) a nd formation of the new complexes [Au3X(mu-S2CNMe2){mu(3)-(PPh2)(3)CH}]ClO4 (X=Cl (3), X=C6F5 (4)); further reaction of 3 with [Ag(OClO3)(tht)] (tht=t etrahydrothiophene) affords the dicationic species [Au-3(mu-S2CNMe2){mu(3)- (tht)](ClO4)(2) (5). Treatment of [Au3Cl3{mu(3)-(PPh2)(3)CH}] with one equi valent of NaS2CNMe2 allows the substitution of only one chlorine atom, givi ng rise to the complex [Au3Cl2(S2CNMe2){mu(3)-(PPh2)(3)CH}] which the dithi ocarbamate ligand acts as monodentate rather than bidentate bridging as obs erved in compounds 3-5. The crystal structures of complexes 1 and 2 have be en established by X-ray diffraction studies and show close gold-gold contac ts.