Synthesis, Structures And Property Of Transition Metal Complexes With Benzene-1,3,5-tricarboxylate And 1,2,4-triazole As Ligands

This dissertation, with using benzene-1,3,5-tricarboxylate and 1,2,4-triazole as main ligands, presented the synthesis of ten two-dimensional (2D) and 3D coordination compounds. Through the structural investigation of the complexes we found that the conditions, such as acidity of solution, anion, temperature and so on, have more or less influence on the assembly of the complexes. In the mean time, by the analysis of their photoluminescent spectrum, we found that properties of compounds are corresponding to their structures. Herein, the thesis discuss the structures and properties of these compounds in three subsections based on the classification of complexes.In Chapter one, a brief introduction was given to the development of coordination chemistry and applications of coordination compounds, meanwhile, the development of benzene - polycarboxylic acid and triazole coordination chemistry were emphasized. Finally the intention and significance of this study were elucidated.The second part systematically investigated the hydrothermal reactions of benzene-1,3,5- tricarboxylic acid and triazole with Cu(II) and Cd(II) salts under different conditions, thereby, obtaining 5 new complexes, [Cd(Hbtc)(H2O)2] (1), [Cd2(btc)(trz)](H2O) (2), [Cu(Hbtc)](H2O)3 (3), [Cu3(Hbtc)(trz)4]·8H2O (4) and [Cu10(btc)4.7(trz)6(μ3-O)H2O]·40H2O (5). The results revealed that the reactions, in the absence of triethylamine, give the uniligand 1 and 3, with triazole free of coordination, while, in the presence of triethylamine, give the mixligand complexes, 2, 4 and 5. The outcomes are illustrative of the dominating effect of solution acidity on the formation of products, specifically, a basic condition favors the coordination of trizaole. In such a sense, one can expect to control the formation of complexes by controlling the medium. In addition, we also investigated the effect of temperature.Chapter 3 explores the effects of ligands and anions on the assemblies of complexes. Under hydrothermal conditions, complexes [Cu6(trz)4(btc)Br] (6), [Cu6(trz)4(btc)Cl] (7), [Cu6(trz)2(btc)(Hbtc)2(H2btc) (μ3-O)2 (μ2-O)(OH) 2Cl]·5 H20 (8), [Zn5(trz)2(btc)4(H2O)4] (9), [Cu2(trz)(btc)(H2O)] (10) were prepared and characterized by IR spectroscopy and X-ray crystallography. It was revealed that the complexes, 6 and 7 are isomorphic, as the supermolecules aggregated throughπ-πinteraction and Cu…Cu weak interactions. Structurally, the compounds, 8, 9 and 10, are analogous, all containing 2D M-trz networks as building blocks, where the benzenetricarboxylates are acting as bridging linkers of 2D M-trz networks and enable the complexes developing into 3D frameworks. Owing to using different metal ions and anions in the reactions, the products provide the samples for the study of the influence of metal and anions on the assembly of coordination polymers.