Synthesis, Structure And Properties Of Copper(Ⅰ) Complexes Based On 3, 5-Bis(2-Pyridyl)-Pyrazole Ligand

This thesis mainly focuses on the solvothermal syntheses, structures and properties of some new copper(I)-pseudohalide frameworks containing 3,5-bis(2-pyridyl)-pyrazole ligand. In the synthetic procedures of these novel complexes, some interesting solvothermal reactions, such as Ring-Opening Supramolecular Isomerism Reaction and Sulfur Transformation Reaction, have been found and studied. Moreover, the template synthesis of some interesting anionic copper(I)-pseudohalide infinite networks templated with cationic metal complexes has been targeted, and the luminescent and magnetic properties of these complexes have been examined. The thesis is divided into three chapters.In the first chapter, the background of this work is briefly reviewed. Literature surveys on the research trend of ring-opening supramolecular isomerism, as well as a summary on our ongoing sulfur transformation project, are presented. Some aspects on the template synthesis in the sulfur transformation are also highlighted. At the end are presented the perspective and progress of this work.In the second chapter, six 0D/1D supramolecular ring-opening complexes formed by the self-assembly of Cu(OH)2, 3,5-bis(2-pyridyl)-pyrazole (Hbpypz) in solvothermal conditions are introduced. A mixture of Hbpypz and Cu(OH)2 in 1:2 ratio was heated at 140°C, and 1D helical-chain polymers [Cu4(CN)2(bpypz)2]n (1 and 2) were found. However, when the reaction temperature rose to 180°C, tetranuclear complexes [Cu4(CN)2(bpypz)2] (3 and 4) were obtained. In contrast, the mixture of Hbpypz and Cu(OH)2 in 1:6 ratio yielded 1D helical-chain polymer [Cu6(CN)4(bpypz)2]n (5). While the mixture of PPh3, Hbpypz and CuSCN in solvothermal condition gave hexnuclear complex [Cu6(CN)4(bpypz)2] (6). Given a mixture of Hbpypz and CuSCN in 1:8 ratio, 2D coordination polymers [Cu9(CN)9(bpypz)4]n 7 were found. Interestingly, CN- was in-situ generated during the syntheses.The third chapter is divided into two parts. Firstly, a novel type of sulfur transformation reaction is introduced. Reactions of NaSCN, PPh3 with CuBr2 under solvothermal conditions were carried out, in one of which the structure of 8 are formed by the coordination of CuI with 2,6-dimercapto-4-methyltriazine in 1:1 ratio. Interestingly, the ligand was in-situ generated during the synthesis. The second part focuses on the utilization of cationic metal-Hbpypz-complex templates to direct the fabrication of anionic copper(I)-pseudohalide networks. A mixture of NiSO₄·6H₂O (or ZnSO₄·7H₂O), NaSCN, Hbpypz, aqueous ammonia and water in solvothermal condition yielded complexes [{M(μ-L)₃}₂{M₃(μ-OH)}]·(SCN)₃·6H₂O (M=Ni²⁺ 9 or Zn²⁺ 10), which were characterized to be triple-stranded cluster helicates. When performing the solvothermal reactions of complexes 9 (or 10), CuSCN, and PPh3, two novel coordination polymers were obtained, namely [Cu₁₂(CN))(11)(SCN)₄]·[{M(μ-L)₃}₂{M₃(μ-OH)}] (M=Ni²⁺ 11 or Zn²⁺ 12), with unusual 3D CuSCN/CuCN anion network encapsulating [{M(μ-L)3}2{M3(μ-OH)}]3+ cluster helicates cations, which acted as templates to direct the formation of 1D CuSCN/CuCN helical tubes in the anion networks. The resulting complexes indicate that the employment of cationic metal complexes as templates to implement helix-to-helix induction is feasible. Besides, the cluster helicates embedded in the host framework offer fascinating possibilities for exploring functional coordination materials. In this work, the complexes were functionalized by varying the metal ions in the cluster helicates fromNi2+ (9 and 11, which exhibits magnetic exchange) to Zn2+ (10 and 12, which is photoluminescent).