Synthesis, Photophysical Properties, and Molecular Aggregation of Gold(I) Complexes Containing Carbon-Donor Ligands

A series of gold(I) complexes with N‐heterocyclic carbene (NHC) and acetylide ligands, namely [Au(NHC1)(C≡CAr)] (NHC1=1‐(9‐anthracenylmethyl)‐3‐(n)‐butylimidazol‐2‐ylidene; 1 b–1 g), [Au(NHC2)(C≡CAr)] (NHC2=1,3‐diethylimidazol‐2‐ylidene; 2 b–2 f) and [Au(C≡NAr)2]+ (C≡NAr=arylisocyanide; 3 a–3 f) have been synthesized. At room temperature, most of these gold(I) complexes are emissive in the solid state and in solutions with lifetimes in the nanosecond to submicrosecond regime. The emissions of complexes 1 b–1 g in solutions are assigned to 1π–π* excited states of the NHC ligand, while that of 2 b–2 f and 3 a–3 f are phosphorescent in nature. The intriguing solvatochromism of complex 3 a was also investigated. Complexes 1 b, 1 d, 3 a, and 3 e aggregate into crystalline nanowires in freshly prepared THF/water dispersions. The X‐ray crystallographic data reveal that 1 b and 1 d possess intermolecular π–π and CH⋅⋅⋅π interactions; while 3 a was found to display intermolecular gold(I)⋅⋅⋅π interactions. Glowing gold! A series of gold(I) complexes with N‐heterocyclic carbene, acetylide, and isocyanide ligands have been synthesized. At room temperature, most of these gold(I) complexes are emissive in the solid state and in solutions with emission lifetimes in the nanosecond to submicrosecond regime. Four complexes were found to aggregate into crystalline nanowires/nanobelts in freshly prepared THF/water dispersions.