Novel Silver-Containing Supramolecular Frameworks Constructed by Combination of Coordination Bonds and Supramolecular Interactions

The hydrothermal reactions of AgNO3, 4,4ʹ-bipy, and carboxylate ligands gave rise to three supramolecular architectures, namely [Ag (bipy)]·H2SIPA·1/2bipy·H2O (1), [Ag(bipy)]·1/2H2btec·H2O (2), and [Ag(bipy)]2·H2dpstc·2H2O (3) (H3SIPA = 5-sulfoisophthalic acid, bipy = 4,4ʹ-bipyridine, H4btec = 1,2,4,5-benzenetetracarboxylic acid, H4dpstc = 3,3ʹ,4,4ʹ-tetracarboxydiphenyl sulfone). All complexes are extended from Ag-bipy linear chains by the combination of coordination bonds and supramolecular interactions in two different approaches. Complexes 1 and 3 comprise two-dimensional frameworks. In the two complexes, a one-dimensional ladderlike structure is first formed by the connection of a Ag-bipy chain through hydrogen bonding between a free carboxylate/bipy ligand and weak coordinative interactions between a free carboxylate ligand and silver ion. The ladderlike structure is then extended to a twodimensional layer architecture by (pi)··· (pi) interactions between bipy ligands of the Ag-bipy chains. Complex 2 possesses a threedimensional framework. The free H2btec2- ligands form a two-dimensional layer network by hydrogen-bonding interactions between protonated and deprotonated carboxylate groups; meanwhile, (pi)···· (pi) interactions between bipy ligands of Ag-bipy chains also result in a two-dimensional layer. The two layers are further connected by weak Ag-O interactions to generate a three-dimensional supramolecular structure.