Synthesis, Characterization And Properties Of Terpyridine Zn(Ⅱ)/Cd(Ⅱ)/Cu(Ⅱ) Complexes

In this paper, two different substituted 2,2':6',2"-terpyridines, 4'-(4-methyoxyphenyl) -2,2':6',2"-terpyridine (L1) and 4'-phenyl-2,2':6',2"-terpyridine(L2) were prepared using Kr?hnke procedure. Seven coordination complexes, [Zn(L1)2](ClO4)2 (1); [Cd(L1)2](ClO4)2 (2); [CdCl2L2]·DMF (3); {[Zn(tp) L1]·H2O}n (4); [Cu2(tp)(L1)2 Cl2]·H2O(5); [Cu(mp)L1]2·H2O(6) and {[Cu(tp) L1]·H2O} n(7), have been synthesized by the hydrothermal / solvothermal reactions from these two ligands and appropriate zinc, cadmium or copper salts as starting materials. All of these complexes were characterized by infrared spectrum, elemental analysis, thermo-gravimetric analysis and fluorescence spectroscopy. Their crystal structures have been established by single-crystal X-ray diffraction.Compared these structures of the seven kinds of complexes, complex 4 and 7 are coordination polymers, complex 5 is a bi-nuclear structure, and the others are single nuclear structures. Complex 3, 5 and 6 are bonded into supramolecular structure resulting from inter-molecular hydrogen bond interaction. The results showed that anionic and ancillary ligand have a great impact on the formation of crystal structure of the complexes. As one kind of bridging ligands, terephthalic acid is more efficient in the synthesis of terpyridine coordination polymers through molecular recognition and assembly.In addition, the fluorescence properties of the coordination complexes were also studied. The fluorescence spectroscopies were measured in liquid or solid state at room temperature. Compared the influence of different substituted terpyridine and various metal ions on the fluorescence properties, some basic research for their potential applications have been done.