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.

Graphical abstractFour new gold(I) complexes are reported. The metal atoms are coordinated by thiosaccharinate anions and by other ligands (PPh3, dppm and dppe). The crystal structure of two of them, [Au(tsac)(PPh3)] and [Au2(tsac)2(dppm)]·EtOH are solved applying single crystal X-ray diffraction and are studied using the density functional theory (DFT) formalism.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Four new binary and ternary gold(I) thiosaccharinates are described. ► The crystal structures of [Au(tsac)(PPh3)] and [Au2(tsac)2(dppm)]·EtOH are presented. ► The complexes were theoretically studied applying DFT. ► The study indicates that an aurophilic interaction exists in [Au2(tsac)2(dppm)]·EtOH.