Synthesis, Structure And Properties Of Transition Metal Complexes Based On Substituted Triazole Ligands

Coordination polymer as a new type of multi-functional composite crystal materials attracts chemist's attention. Coordination polymer research has made outstanding achievements. A large number of research results show that the influence of coordination polymer architecture depends on constructing module (organic ligands, metal center, counter ion, and solvent molecules) and coordination co-existence. How to reasonably choose and design the appropriate molecular base building module is one of the important factors in the synthesis of complexes. We mainly intends to synthesis and choose contain donors asymmetric3,5-disubstituted1,2,4-triazoles ligands and construct coordination polymers by self-assembly. This kind of ligand increasing with coordination sites, further enhancing the skeleton trizole ligand length at the same time, can be used as a very good bridging ligand, which is expected to obtain novel metal organic framework materials with good performance,In this paper,3-amino-lH-1,2,4-triazole-5-acetate ligand is designed and synthesized and3-(2'-pyrazine)-5-(4'-pyridine)-1,2,4-triazole (Hppt) ligand is choosed. These ligands have been used to react with metal ion to afford twenty-two new complexes. Structures of them have een determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and thermogravimetric analysis. Furthermore, photoluminescence and magnetic properties of some complexes were also investigated. We have studied the influence of many factors, such as anionic-controlled and solvent-controlled and auxiliary-controlled the formation of various structural types. The main contributions in this work are blow:1. We have designed and synthesized Hatrza ligand. Six complexes have been synthesized by the ligand and different metal salts. Complexes1-6are discrete OD structures. These are abundant intermolecular H-bonds in their packing structure. The units were connected as three dimension structure by the intermolecular H-bonds. Also, the thermal stabilities were discussed.2. Six complexes haved been synthesized by using Hppt ligand and metal salts. The complexes7-9containing Cd(II) ions are2D layer structure. The halogen ions have no the effects of structure. There are large differences on thermostability of them. The complexes10?11and12are0D?3D and ID, respectively. The results show that distorting of ligand influences on coordination mode. And the thermal stabilities and luminescent properties of compounds7-10were carried out.3. Compounds13-16have been successfully synthesized by the self-assembly of Cd(?), Hppt ligand, and carboxylate ligands. Compound13shows a2-fold interpenetrating2D wave-like structure. Compounds14and16are complexity3D net. Compound15reveals a2-fold interpenetrating3D framework. And the thermal stabilities and luminescent properties were carried out and analyzed.4. Six new complexes17-22have been obtained from the self-assembly of the Hppt ligand with different metal salts, in the presence of coligands. Compounds17and19are new supramolecular architectures. Compound22reveals a novel interesting2D?3D parallel polycatenation network. Compounds20and21are two isomorphic2D net. Different auxiliary ligand has obvious influence on dimension of compounds. Moreover, the magnetic properties of compounds19and20were studied, and they display weak antiferromagnetic character. At the same time, the thermal stabilities of17and19, the luminescent properties of17and21were tested and discussed, respectively.