Synthesis, Structure And Properties Of Complexes Derived From The New N-Containing Heterocycle Ligands

Over the last10years, the design and synthesis coordination complexes has been ainteresting field in recent years. The diversity of structure and property of coordinationpolymer may have potential application in many fields. The recent research has beenfocused on the synthesis of new ligands and analysis topology of the coordinationcomplexes. There are a lot of reports about coordination complexes, but it was still aattractive area of research in the future. Design and synthesis of new ligands and researchthe novel synthetic methods would be required in order to create more innovativestructures with unique properties.Seven unreported coordination complexes have been hydrothermally synthesized orsolvent evaporation process based on N-containing heterocycle ligands, polycarboxylicacids and metal salts. These complexes were characterized by element analyses, IRspectroscopy, power X-ray diffraction and X-ray single crystal diffraction. The TG,fluorescence and catalytic properties of the complexes also have been investigated.Four complexes based on two flexible benzimidazole ligands and1,2,4-triazole havebeen synthesized, namely:{[Cd(btc)(L1)]·(H2O)2}n(1)，(Cd2L1Cl4)n(2)，{[Zn5(L3)4(5-NO2-H2bdc)3(3H2O)]·4H2O}n(3) and {[Co2(H4btec)(L2)2]·4H2O}n(4). Complexes1and2derived from ligands L1, with the structure of binodal (3,5)-connected network and atwo dimensional supramolecular architectures by hydrogen bonding interactions,respectively. Complexes3is a rare three dimensional trinodal (3,4,7)-connected MOF,named cgh3. Complex4is a two dimensional binodal (3,4)-connected network with pointsymbol of {4.62}2{42.62.82}.Three mononuclear complexes have been synthesized based on benzimidazole (L4)and its derivative5,6-dimethylbenzimidazole (L5) with pyridine-2,6-dicarboxylic acidby solvent evaporation or hydrothermal method:[Ni(H2pydca)(L4)3](5),[Ni(H2pydca)(L5)3](6),[Co(H2pydca)(L5)3](7). These complexes are connected into2D/3D supramolecular network through N-H···O hydrogen bond interaction.The solid fluorescence analysis showed that complexes1~4can emit fluorescenceunder the excitation of certain wavelengths of UV light and then they can be used as thepotential fluorescent materials. Complexes4and7show good catalytic activity incatalytic degradation of azo dye, such as methyl orange and congo red.