Synthesis and Characterization of Cobalt Complexes of Heterocyclic Bidentate Ligands (N,X), X= S, Se

Abstract

AbstractThe synthesis and structural characterization of a series of homoleptic cobalt complexes of general formula [Co(R‐pyX)3] is reported, where X = S, Se; R = H, 3‐CF3 and 5‐CF3. The compounds were synthesized by electrochemical oxidation of the metal in a cell containing an acetonitrile solution of the corresponding ligand. When 2,2′‐bipyridine (bipy) or 1,10‐phenanthroline (phen) were added to the electrolytic cell, mixed cobalt(II) compounds [Co(R‐pyX)2L] (L = bipy, phen) were also isolated. All of the complexes obtained have been characterized by microanalysis, vibrational and electronic spectroscopy, FAB mass spectrometry and, in the case of diamagnetic compounds that were sufficiently soluble, by 1H and 13C NMR spectroscopy. Crystals of [Co(3‐CF3‐pyS)3] and [Co(5‐CF3‐pyS)3] were obtained and studied by X‐ray diffraction. The crystal structures consist of monomeric molecules with the metal atom in an octahedral environment and the ligands in a meridional disposition.