Crystal structure of a pentanuclear gold-silver cluster complex

The title compound, C₁₆H₃₆N]⁺C₄₈H₃₀Au₃Ag₂]^–, crystallizes in the triclinic space groupP1^–1, witha=18.199(12),b=19.210(8),c=19.270(9)Å,=71.34(3)°=76.43(4)° =72.95(5)° andZ=4, with two independent molecules in the asymmetric unit. The structure was solved by direct methods and refined by full-matrix least squares methods toR=0.072 for 3739 observed reflections. The metal atoms have a trigonal-bipyramidal arrangement with the three Au atoms forming an equilateral triangle and two Ag atoms occupying apical positions. Each Au atom is -bonded to phenylethynyl ligands in a linear coordination. Each Ag atom is asymmetrically pi-bonded to three alkyne groups. The Au-Au distances lie in the range of 3.934–4.010 A, indicating the lack of Au-Au bond.