Coordination Polymers from Functionalized Bipyrimidine Ligands and Silver(I) Salts

Abstract

Readily functionalizable bipyrimidine compounds were prepared for the first time, and their coordination chemistry with silver salts was explored. Solution 1H NMR spectroscopy experiments indicated that the ligands rapidly form complexes with silver­(I) salts, and coordination at a first site inhibits coordination of a second cation to the ligand, thus favoring 1:1 complexes in solution. These 1:1 units self-assemble into one-dimensional chains in the solid state, even in the presence of excess Ag­(I). Structurally diverse coordination polymers exhibiting different coordination numbers and geometry were characterized by single crystal X-ray crystallography. Our results demonstrate that a modification to the ligand, distal from the binding site, affects the coordination chemistry and supramolecular structure of these complexes.

Synthesis, Structural Characterization, and Water Vapor Sorption Behavior of Two Ligand Ratio-Dependent Supramolecular Networks, [Cd(2,2′-bpym)1.5(BDC)]·0.5(2,2′-bpym)·5H2O and [Cd(2,2′-bpym)0.5(BDC)(H2O)3]

“…Nevertheless, 2,2′-bpym shares the key feature of each of these ligands: a π-conjugated pathway that can mediate electronic or magnetic interactions between metal centers. 33 Recently, porous 3D MOFs have been examined for their water capture properties, and they were found to be highly promising materials. 34 − 36 Water adsorption in MOFs can occur following three distinct pathways: chemisorption on open metal sites, physisorption in the form of layers or clusters, or capillary condensation.…”

“…Unlike 5,5′-bpym acting as bridging ligands with μ-type multi-monodentate coordination modes, 2,2′-bpym can coordinate with metal ions with chelating or bis -chelating coordination modes. Nevertheless, 2,2′-bpym shares the key feature of each of these ligands: a π-conjugated pathway that can mediate electronic or magnetic interactions between metal centers . Recently, porous 3D MOFs have been examined for their water capture properties, and they were found to be highly promising materials. − Water adsorption in MOFs can occur following three distinct pathways: chemisorption on open metal sites, physisorption in the form of layers or clusters, or capillary condensation. , However, water capture behaviors applied on 3D supramolecular networks assembled via 0D metal complexes, 1D CPs, or 2D MOFs are seldom, and only few cases have been examined. − In our previous study, we have successfully synthesized a series of 2D or 3D MOFs constructed using Cd­(II) with 2,2′-bpym and oxocarbon dianion (C n O n 2– , n = 4, 5, 6) ligands, creating interesting structural topology. , On the other hand, the 2,2′-bpym can be used as an ancillary ligand, together with the carboxylate ligand, to meet the requirement of coordination geometries of metal ions in the assembly process.…”