Conformational behavior, redox and spectroscopic properties of gold dithiolene complexes: [Au(iPr-thiazYdt)2]−1 (Y = O, S, Se)

Abstract

Three monanionic gold dithiolene complexes with different exocyclic chalcogen atoms (O, S, Se) on the N-isopropyl-1,3-thiazoline-2-chalcogenone-4,5-dithiolate ligand, have been synthetized with the aim of modulating their properties. Due to the presence of the isopropyl (iPr) group in the plane of the thiazoline-2-chalcogenone ring, different syn and anti rotamers can exist, in solution and in the solid state. Characterization of these complexes by spectroscopic and electrochemical methods was carried out in order to investigate the influence of the size, electronegativity and polarizability of the exocyclic chalcogen atom. The molecular structure of the three anionic complexes [Au(iPr-thiazYdt)2]−1, with Y=O, S, Se, were established by single crystal X-ray diffraction studies. Theoretical calculations carried out at the DFT levels were realized on the three possible rotamers, syn/syn, syn/anti and anti/anti of the trans-[Au(iPr-thiazYdt)2]−1 complexes.