Silver(I) cis-diphenylphosphinoethylene complexes: Spectroscopic and structural characterization

Adducts of the diphosphine cis-Ph₂P(CHCH)PPh₂ (L) with AgX (X = NO₃, BF₄, ClO₄ or CF₃SO₃) have been synthesized and characterized both in solution (¹H, ³¹P NMR) and in the solid state (IR, single crystal X-ray structure analysis). The topologies of the structures in the solid state were found to depend on the nature of the counter-ion X. The adduct AgNO₃:L (2:1)₂ is tetranuclear, derivative of the chair form, the bidentate ligands bridging peripheral silver centers, the nitrates being coordinated through two oxygen atoms, the first O,O′-bridging the second bridging bidentate.