Syntheses, Structures and Properties of Coordination Polymers with Aromatic Dicarboxylates
|Keywords||Aromatic Carboxylic Acid Coordination Polymers Hydrothermal Synthesis Crystal Structures Luminescence Properties|
Recently, the field of metal-organic frameworks (MOFs) has been attracted tremendous attention owing to their intriguing structural motifs, morphologies and potential applications as catalysis, optoelectronic, magnetic and luminescent materials. The carboxylate groups with diverse coordination modes have been widely used as building blocks in construction of the coordination frameworks.With this background in mind, the aroma dicarboxylates are employed as bridging linkers and neutral N-donor co-ligands as terminal or bridging ligands in combination with Zn2+or Cd2+. Thus,10 coordination polymers have been successfully prepared under hydrothermal conditions and characterized by IR, X-ray single crystal diffraction, TGA and luminescence analyses as well.There are three parks in the text:1. One new two dimensional coordination polymer 1 with double-layer has been synthesized under DMF solvothermal conditions using the unsymmetrical carboxylate groups biphenyl-3,4’-dicarboxylate (3,4’-H2bpdc), Cd2+,4,4’-bpy and HNO3. Interestingly, the guest DMF molecules occupancied the holes in the double-layer. The guest DMF molecules in 1 can be also exchanged by EtOH quickly and H2O step by step.2. Seven new coordination polymers (2-8) with one dimensional or two dimensional have been synthesized under hydrothermal conditions using the unsymmetrical carboxylate groups biphenyl-3,4’-dicarboxylate (3,4’-H2bpdc) and 2,4’-H2bpdc, Zn2+ and neutral N-donor co-ligands. It has been demonstrated that the structural geometry could be controlled and modulated by selecting an appropriate neutral N-donor co-ligands. In compounds 2-8, the Zn ion was firstly connected by 3,4’-bpdc or 2,4’-bpdc to one dimensional chain subunits, which were further connected by the flexible briding or rigid chelating N-donor co-ligands to form 2D or 1D final structure.3. Two new two dimensional coordination polymers have been synthesized under hydrothermal conditions using the carboxylate groups CH3-BDC, Cd2+and 1,4-di (1H-imidazol-2-y1)butane in different pH conditions.