Inorganic Chemistry, Vol.45, No.19, 7770-7776, 2006
Gold(I) and silver(I) mixed-metal trinuclear complexes: Dimeric products from the reaction of gold(I) carbeniates or benzylimidazolates with silver(I) 3,5-diphenylpyrazolate
Trinuclear mixed-metal gold-silver compounds are obtained by the reaction of gold(I) carbeniate [Au(mu-C(OEt)=NC6H4-p-CH3)](3) , TR(carb), or gold(I) imidazolate [Au-mu-C, N-1-benzyl-2-imidazolate](3), TR(bzim), with silver(I) pyrazolate [Ag(mu-3,5- Ph(2)pz)](3). The crystalline products are mixed-ligand, mixed-metal dimeric products [Au(carb)Ag-2(A-3,5Ph(2)pz)] [Au-2(carb)(2)Ag(mu-3,5-Ph(2)pz)](CH2Cl2)-C-., [Au(bzim)(2)Ag-2(mu-3,5-Ph(2)pz)], and [Au-2(bzim)(2)Ag(mu-3,5-Ph(2)pz)]. They have been characterized by elemental analysis and H-1 NMR and mass spectrometry. The X-ray structure of [Au(carb)Ag-2(mu-3,5- Ph(2)pz)(2)] shows it to be a dimer with two (AgAu)-Au-... contacts between the trinuclear units of 3.083( 2) and 3.310(2) angstrom and with average intramolecular (AgAg)-Ag-... and (AuAg)-Ag-... distances of similar to 3.3 and 3.2 angstrom respectively. The structure of [Au-2(carb)(2)Ag(mu-3,5-Ph(2)pz)](CH2Cl2)-C-. is a dimer with one intermolecular Au,,, Au attraction of 3.3354 (10) angstrom and a short (AgAu)-Au-... distance of similar to 3.42 angstrom and intramolecular (AgAu)-Au-... and (AuAu)-Au-... contacts of similar to 3.2 and similar to 3.3 angstrom, respectively. Packing diagrams of both complexes show that the dimeric units are independent, similar to their parent molecules. The dimers of trinuclear [Au(carb)Ag-2(mu-3,5-Ph(2)pz)(2)] and [Au-2(carb)(2)Ag(mu-3,5-Ph(2)pz)](CH2)-C-.-Cl-2 crystallize in the triclinic space group P1 (Z = 2), a = 9.688(3) angstrom, b = 15.542(4) angstrom, c = 23.689(6) angstrom, alpha = 82.560(5)degrees, beta = 87.887(6)degrees, gamma = 78.060(5)degrees, and the orthorhombic space group Pca2(1) (Z = 4), a = 29.644(4) (angstrom), b = 7.4582(10) angstrom, c = 30.473(4) angstrom, respectively. The structure of [Au(bzim)Ag-2(mu-3,5-Ph(2)pz)(2)] is a dimer with two metallophilic (AgAu)-Au-... interactions of 3.14 angstrom. The complex crystallizes in the monoclinic space group C2/c (Z = 4), a = 26.368(5) angstrom, b = 15.672(3) angstrom, c = 17.010(3) angstrom, beta =102.206(3)degrees.