Aurophilic interaction in gold(I) thiosaccharinates: Synthesis, characterization, crystal structures and DFT theoretical study

The reaction of gold with thiosaccharin ligand and additional phosphorous coligands is studied. Four new Au(I) complexes with thiosaccharinate as coordinating counteranion: [Au(tsac)(PPh3)], [Au2(tsac)2(dppm)]·EtOH, Au2(tsac)2(dppe)·EtOH, and Au(tsac)(Htsac)2·0.25 EtOH (tsac: thiosaccharinate, C6H4C(S)NSO2−, dppm: bis(diphenylphosphino)methane, dppe: bis(diphenylphosphino)ethane) were synthesized and characterized by means of spectroscopic techniques (IR, UV–Vis, and 1H, 13C and 13P NMR). The crystal structure of two of them, [Au(tsac)(PPh3)] and [Au2(tsac)2(dppm)]·EtOH, were solved applying single crystal X-ray diffraction and studied using the density functional theory (DFT) formalism. In the latter, the aurophilic interaction between the two gold centers was analyzed and theoretically confirmed.