Noncovalent Synergy: Aurophilicity and Aryl Stacking in Bis(gold(I)aryl)-dmpm Complexes.

Abstract

Bis(dimethylphosphino)methane (dmpm) was used as a ligand to synthesize four semi-supported dinuclear gold(I) complexes, dmpm(AuR)2 (R = Cl, C6H5, C6Cl5, and C6F5), which were studied concerning the synergistic effects of two weak noncovalent interactions: aurophilic and aryl-aryl stacking interactions. The chloro-substituted complex was synthesized by the ligand substitution of (tht)AuCl with dmpm and further functionalized by the reaction with PhMgBr or in situ-generated C6Cl5Li to afford the phenyl- and pentachlorophenyl-substituted compounds, respectively. The pentafluorophenyl-substituted gold complex was generated by the ligand substitution of (tht)Au(C6F5) with dmpm. All complexes were characterized by multinuclear NMR spectroscopy, CHN analyses, and X-ray diffraction experiments. Additionally, the basic photoluminescence properties of dmpm(AuCl)2, dmpm(AuC6Cl5)2, and dmpm(AuC6F5)2 were examined. The aggregation behavior of dmpm(AuC6F5)2 was further investigated by variable-temperature diffusion-ordered NMR spectroscopy experiments.