title: Formation and structure of two luminescent salts of [Au(SCSN3)2]- obtained through the [2 + 3] cyclization of carbon disulfide and azide ion.
abstract: The colorless, two-coordinate gold(i) complex, [(H2O)3Na][Au(SCSN3)2], has been synthesized through the [2 + 3] cyclic reaction of carbon disulfide and sodium azide in the presence of the labile complex (tht)AuCl. Metathesis of [(H2O)3Na][Au(SCSN3)2], with tetra(phenyl)arsonium chloride produced colorless needles of (Ph4As)[Au(SCSN3)2]. The structure of [(H2O)3Na][Au(SCSN3)2] involves linear gold coordination by two exocyclic sulfur atoms of the 1,2,3,4-thiatriazole-5-thiolate anions. These two-coordinate anions self-associate to form extended, zig-zag chains that are connected by aurophilic bonding with Au∙∙∙Au distances of 3.2653(3) Å and 3.3090(3) Å. Remarkably, the individual S-Au-S units that are connected though aurophilic interactions are eclipsed. The structure of (Ph4As)[Au(SCSN3)2] also contains linear, two-coordinate gold ions with bonding to the 1,2,3,4-thiatriazole-5-thiolate anionic ligands through the exocyclic sulfur atoms. However, in this salt, the anions self-associate through AuAu bonds (Au∙∙∙Au distance of 3.2007(3) Å) to form simple dimers, which also have an eclipsed arrangement of the ligands. Electronic structure calculations strongly suggest that the staggered geometry for the [(Au(SCSN3))2](+) dimer is energetically favored relative to the eclipsed geometry. However, attractive π-stacking interactions appear to promote the observed eclipsed arrangement of the ligands.
authors.affiliation: Department of Chemistry, University of California, Davis, California 95616, USA. albalch@ucdavis.edu.
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Lim
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Schmitt
authors.forename: Jason
authors.initials: J
authors.lastname: Shearer
authors.forename: Kellie R
authors.initials: KR
authors.lastname: England
authors.forename: Marilyn M
authors.initials: MM
authors.lastname: Olmstead
authors.forename: Alan L
authors.initials: AL
authors.lastname: Balch