Compounds Based On Nitrogen Heterocyclic, Carboxylicligand: The Syntheses, Structures And Properties

The field of metal coordination polymers has attracted much attention and continuously evolved in recent decades. The driving force for this is because of not only from their fancy structural characteristics, but also because of their immesurable application value in magnetism, gas adsorption, catalysis, ion recognition and so on. Considerable efforts have been devoted and many metal coordination compounds with characteristic structures and special performances have been synthesized. Among them, novel coordination polymers based on aromatic carboxylic acid or N-donor ligands and various metal ions have caught particular attention. In this work, we select mainly two organic ligands, one is [1,1’:3’,1’’-Terphenyl]-3,3’’,5,5’’-tetracar-boxylic acid(H4tpta), which is employed to react with different metal ions under hydrothermal condition to get eight coordination polymers with diverse structures. These coordination compounds were determined by X-ray single crystal diffraction. Elementary analysis, IR and thermogravimetric analyses were conducted for further investigation. We also studied the magnetic properties of some coordination polymers. Another one(ligand) is 2,6-bis(3-(pyrid-3-yl)-1,2,4-triazolyl) pyridine(H2bptp), with which we synthesized three Cd(II) complexes. Moreover, these complexes are applied to the reaction of photocatalytic degradation of MB under high-pressure mercury lamp irradiation. This paper contains following two parts: 1. By employing a tetradentate acid ligand H4 tpta and different N-donor ligands, eight metal-organic frameworks compounds 1-8 are hydrothermally synthesized. Complexes 1-8 manifest diverse structural characteristics with noncluster and polyclusters as SBUs, respectively, indicating the significant role of the carboxylate coordination modes and the auxiliary N-donor ligands in tuning the SBUs as well as determining the final structures. In addition, the magnetic property of compounds 1, 2, 4 indicates that compound 2 and 4 display unusual ferromagnetic coupling via the M-O-C-O-M bridges, while compound 1 shows predominantly antiferromagnetic behavior.2. Three distinctive cooedination compounds 9-11 have been generated by the combination of H2 bptp, two different polycarboxylate auxiliary ligands and Cd(II) ions. The results indicate that auxiliary ligands play a significant role in tuning the structures and properties of the complexes. Furthermore, these complexes are applied to the reaction of photocatalytic degradation of MB under high-pressure mercury lamp irradiation. Both complexes 9 and 11 exhibit good photocatalytic properties. The UV-vis absorption and photoluminescent emissions of 9-11 were also investigated.