From {Au~Ⅰ...Au~Ⅰ}-Coupled Cages to the Cage-Built 2-D {Au~Ⅰ...Au~Ⅰ} Arrays: Au~Ⅰ...Au~Ⅰ Bonding Interaction Driven Self-Assembly and Their Ag~Ⅰ Sensing and Photo-Switchable Behavior

摘要

Metal-metal bonding interactions have been used to generate a number of unique supramolecular assemblies with fascinating functions. We presented here a new class of gold(Ⅰ)-containing metallosupramolecular cages and cage-built two-dimensional (2-D) arrays of {Au_8L_2}_n (n = 1 or ∞, L = tetrakis-dithiocarbamato-calix[4]arene, TDCC), 1-3, which are constructed from the self-assembly of deep-cavitand calix[4]arene-based supramolecular cages consisting of octanu-dear Au(Ⅰ) motifs. Synchrotron radiation X-ray diffraction structural analyses of 1-3 revealed their quadruple-stranded helicate dimeric cage structure and the presence of 2-D arrays of cages linked together by inter-and intramolecular Au~Ⅰ...Au~Ⅰ interactions. Electronic absorption and emission studies of complexes 1-3 indicated the occurrence of a programmable self-assembly process in a concentration-dependent stepwise manner with the links built via aurophilic interactions. These novel gold(Ⅰ) supramolecular cages exhibited green phosphorescence and have been shown to serve as highly selective proof-of-concept luminescent sensors toward Ag~Ⅰ cation among various competitive transition-metal ions.