Bis(triphenylphosphine)silver(i) perrhenate, a cyclic dimer

Abstract

The 1 : 4 and 1 : 2 complexes of silver perrhenate and triphenylphosphine, [(Ph₃P)₄Ag]⁺ ReO₄⁻ and [(Ph₃P)₂AgReO₄]₂, have been prepared and their structures determined in the solid state by X-ray diffraction. The former is composed of independent ions, while in the latter the ions are aggregated into cyclic dimers. The silver centers are tetracoordinated including contact with two bridging perrhenate anions, setting this structure apart from that of its gold analogue [(Ph₃P)₂Au]⁺ ReO₄⁻ where the gold centers are strictly two-coordinate.