Synthesis and characterization of copper(I) and silver(I) complexes with heterocyclic bidentate ligands (N, X), X = S, Se

Abstract

The synthesis and structural characterization of series of copper and silver homoleptic complexes [M(R-pyX)], M = Cu, Ag, X = S, Se; R = H, 3-CF 3, 5-CF 3 (not all combinations), is described. The copper compounds, as well as [Ag(pySe)] and [Ag(3-CF 3-pySe)], were synthesised by electrochemical oxidation of anodic metal in a cell containing an acetonitrile solution of the corresponding proligand. The other homoleptic silver complexes were obtained by direct reaction between AgNO 3 and the salt of the corresponding ligand in methanol. In addition, the reaction of the metal thiolate compounds with bis(diphenylphosphino)ethane (dppe) in acetone allowed the synthesis of heteroleptic compounds [M 2(R-pyX) 2(dppe) 3]. The compounds obtained have been characterized by microanalysis, IR spectroscopy and mass spectrometry and, in cases where the complexes were sufficiently soluble, by 1H NMR spectroscopy. The proligands (3-CF 3pySe) 2 ( 1), (5-CF 3-pySe) 2 ( 2) and (5-CF 3-pySe-DMF) ( 3) and the complexes [Cu(3-CF 3-pyS)] ( 4), [Ag(3-CF 3-pyS)] ( 5) and [Cu 2(5-CF 3-pyS) 2(dppe) 3] ( 6) were obtained as crystalline products and were studied by X-ray diffraction methods.