Synthesis, Structures And Properties Of New Coordination Polymers Based On 4'-(4-Pyridyl)-terpyridine

The design and synthesis of novel functional coordination polymers have been one of the most interesting research topics in coordination chemistry and crystal engineering. In this dissertation, eighteen transition-metal coordination polymers based on 4'-(4-pyridyl)-terpyridine are designed and constructed successfully. These coordination polymers are characterized by X-ray single crystal diffraction, X-ray powder diffraction, IR spectra, thermal gravimetric analyses and luminescence analyses. This dissertation includes the following five parts:(1) Chapter 1:Introduction, the concepts and principles of coordination chemistry, crystal engineering and coordination polymers are simply introduced. The sorts and synthesis of coordination polymers are presented. At the same time, reviews on the research development of luminescent complexes containing terpyridine ligand are also briefly depicted.(2) Chapter 2:Three isomeric 4'-(4-pyridyl)-terpyridine ligands been designed and synthesized, and three ZnⅡcoordination polymers (1-3) based on 4'-(4-pyridyl)-3,2':6',3"-terpyridine (3-pytpy) have been also synthesized successfully. Complexes 1-3 show different structures,2D layer (1), two-fold 2D layer (2) and 3D network (3). In a comparison of the structures of 1-3, it is found that the final structure can be tuned by the influence of auxiliary organic acid. Complexes 1-3 have strong luminescent intensity and good thermal stability, which can be used as potential fluorescence materials.(3) Chapter 3:Six transition metal coordination polymers (4-9) based on 4'-(4-pyridyl)-4,2':6',4"-terpyridine (4-pytpy) and auxiliary polycarboxylic acids ligands have been synthesized successfully. The structures of complexes 4-6 are varied from ID to 3D, while complexes 7-9 all features interpenetrating honeycomb 3D networks. Complexes 4-6 show strong fluorescence emission upon excitation at 310 nm in solid state. Additionally, these complexes possess great thermal stabilities, especially for 6, the framework is stable up to 350℃. (4) Chapter 4:We have hydrothermally synthesized four new ZnⅡcoordination polymers (10-13) based on in situ ligand synthesis of maleic acid (isomerization and hydroxylation of the ethylene group in maleic acid). In complexes 10 and 11, maleic acid is converted into fumaric acid by the isomerization of the ethylene group. In 12 and 13, maleic is turned into malate by the hydroxylation of the ethylene group. The reason for the happen of in situ ligand synthesis of maleic acid is also discussed.(5) Chapter 5:Five ZnⅡcoordination polymers (14-18) based on 4'-(4-pyridyl)-3,2':6',3"-terpyridine and auxiliary 1,4-benzenedicarboxylic acid ligands with different zinc salts have been synthesized successfully. Our studies show that the counter anions effect plays important role on the formation of the final complexes. The successful synthesis of these complexes may provide some useful information on future synthesis of new complexes with different counter anions.