Structural comparison of cluster compounds containing an edge-bridging M(PPh3)(M = Cu, Ag, or Au) fragment. X-Ray crystal structure of [AgRu3(CO)9(C2But)(PPh3)

Abstract

An X-ray diffraction study of [AgRu3(CO)9(C2But)(PPh3)] shows that the cluster adopts a ‘butterfly’ metal-core structure, with the silver atom occupying a ‘wing-tip’ site. The t-butylacetylide ligand lies on the convex side of the ‘butterfly’ metal core, interacting with all three ruthenium atoms via one σ bond to the ‘wing-tip’ ruthenium site and two π bonds to the ruthenium atoms which form the ‘hinge’ of the ‘butterfly’. Comparison of the structure with those reported for the analogous copper- and gold-containing species reveals that the M–P and M–Ru bond lengths are markedly longer for M = Ag than for M = Cu or Au.