Synthesis,Structures And Properties Of Fransition Metal Complexes With 3-Thione-1,2,4-Triazole Derivatives

In recent years,with the mutual penetration and intercross of different subject realm,the coordination chemistry has developed toward the functional coordination polymers.This trend has found an even greater pace.Coordination polymers containing mercapto-group or N-heterocycle have gained great interest,because they possess variety of structures and excellent properties,and have potential applications in the fields of medicine,biology protein,optics,gas adsorption,magnetic materials,catalytic hydrogen production,nanometer materials,etc.metal-organic frameworks（MOFs）constructed from N/S or N/O ligands,have aroused increasing interest in both academic research and applications,in view of their intriguing variety of architectures along with potentially functional materials.To date,the goal-directed design and construction of the coordination complexes with desired topologies still face with urgent challenge,partially due to organic ligands possessing effective metal coordination sites and diverse coordination modes and some other factors.Therefore,on the base of rational design of organic ligands,it is essential to continuously accumulate and explore the synthetic experience.In this paper,we synthetized three ligands which contain mercapto-group or N-heterocycle:3,3’-bis（1-amino-5-thione-1,3,4-triazole）,3-thione-5-（2-pyridyl）-1,2,4-triazole,4-amino-3-（2-pyridyl）-1H-1,2,4-triazole-5-thione,With the introduction of trigid aromatic carboxylic acids,the ligand 2-aptt H self-assembles with different metal ions to construct seven coordination eight complexes.The detailed explanation is as follows:Section one:We mainly aim at reasearching the advances in 1,2,4-triazole ligands and N-,S-heterocyclic complexes and the factors about affecting the structure-diversity complexes.Section two:Research papers,including the preparation of the sulfur-containing triazole ligands and complexes and the research of their structure and properties.Concrete content is as follows:1.The three 3-thione-1,2,4-triazole ligands,3,3’-bis（1-amino-5-thione-1,3,4-triazole）,3-thione-5-（2-pyridyl）-1,2,4-triazole,4-amino-3-（2-pyridyl）-1H-1,2,4-triazole-5-thione,have been synthesized by our group.Then,we did a study to explore their synthesis methods and various factors which affecting the yields of the ligands.Moreover,the structures of these ligands have been gained through X-ray diffraction analysis.2.Eight novel complexes were separated from the reactions of as-prepared ligands with different metal salts by solvothermal method.The molecular formula of the seven novel complexes are（1）,[Mn（L¹）₂]_n·（2H₂O）_n（2）,[Pb（L¹）₂]_n（3）,Mn（L²）₂（H₂O）₂（4）,Zn（L²）₂（H₂O）₂（5）,[Cd（L³）₂]_n（6）,[Cd₂（L³）₂（Hpma）₂（H₂O）₂]_n（7）,[Cd³（L₃）₂（1,3,5-btc H）₂]_n·（2H₂O）_n（8）[Cd₃（L³）₂(（1,3,5-btc H）₂（H₂O）₂]_n·（2H₂O）_n.The structures of as-prepared complexes have been determined by X-ray diffraction analysis and characterized by IR spectra.Furthemore,solid fluorescence and thermogravimetric analysis of some complexes have been briefly investigated.The ligands L¹were reacted with manganese chloride and lead nitrate,respectively to give complexes（1）-（2）.X-ray single crystal diffraction analysis showed that in the complex（1）,the ligand usedμ₄-η²-η¹-η²-η¹to coordinate with the central metal ion,and the complex（2）wasμ₄-η¹-η¹-η¹-η¹.Coordination with metal ions.The complex（1）is a three-dimensional network structure,and the complex（2）is a two-dimensional network structure.Two heterogeneous isomorphous complexes（3）-（4）were synthesized by reacting ligand L²with manganese chloride and zinc nitrate respectively.In the complexes（3）-（4）,the ligands were allμ₁-η².Pattern coordination.Under the condition of solvothermal conditions,four novel coordination compounds（5）-（8）were constructed by using a mixed ligand strategy composed of a rigid mercapto ligand L³and a carboxylic acid ligand and metal Cd（II）.The complexes（5）and complexes（7）all exhibit a two-dimensional grid structure.The complexes（6）and complexes（8）all have a one-dimensional structure,but due to the difference in ancillary ligands,the structures differ.In this paper,the thermal stability and fluorescence characteristics of the complexes（1）-（8）were studied.The effects of metal ions and ancillary ligands on the crystal structure were preliminary analyzed,and metal ions,ancillary ligands,and crystal structure-pair complexes were investigated.The effect of thermal stability and fluorescence properties.