Use of [SbF6]−to Isolate Cationic Copper and Silver Adducts with More than One Ethylene on the Metal Center

Abstract

A cationic tris(ethylene)copper(I) and tris(ethylene)silver(I) adduct has been isolated using hexafluoroantimonate counterion. X-ray crystallographic analysis shows that the metal atom in these adducts coordinates to three ethylene molecules in a trigonal planar fashion, forming a spoke-wheel arrangement. In [M(C2H4)3][SbF6] adducts (M = Cu, Ag, Au), the average M–C distances of 2.189 A for Cu and 2.410 A for Ag can be compared with the corresponding distance of 2.268 A for Au and show that the copper(I) complex has the shortest while the silver adduct displays the longest M–C distances. These agree well with the computed values (2.172, 2.408, and 2.308 A for Cu, Ag, and Au analogues, respectively) and follow the same trend as the covalent radii of M(I). Structural data on [μ3-Cl{Cu(C2H4)2}3][SbF6]2, which features bis(ethylene)copper(I) moieties, are also presented. It has a trigonal planar Cu3Cl core with a triply bridging chloride ion bonded to three trigonal planar copper centers. Ethylene molecules a...