Design, Synthesis, And Structural Characterization Of Copper (Ⅰ)-pyrazolated Coordination Polymer With Pyridyl Substituents

The design and synthesis of supramolecular complexes featuring special structures are notonly a hot topic, but also an important theme of coordination chemistry all along. However, thestructures of complexes are controlled not only by ligand structure and the inherent properties ofmetal ions but also the reaction conditions.In this work, a series of pyrazole ligands with various pyridyl and other substituents on 3- or5-position of pyrazole ring were designed and synthesized. Using these ligands and copper saltwith various anion as reactants, under different reaction conditions, a series of supramolecularcoordination polymers, from 0D to 1D, non-interpenetrating to interpenetrating and polyknotting,were constructed successfully, which make a strategy come true to construct predesignedsupramolecular complexes featuring interpenetration and potyknotting, as well as 3D topologynetwork with high connectivity node using metal clusters as Secondary Building Blocks (SBUs).In chapter 1, related research progress of supramolecular coordination chemistry wereintroduced: hydro(solvo)thermal in-situ synthesis, the design and synthesis of interpenetratingand polyknotting complexes, the design and synthesis of coordination polymer using metalclusters as SBUs ect. In addition, research work of pyrazole-related coordination complexes wasreviewed briefly, and also purpose and significance of this work were explained.In chapter 2, six kinds of pyrazole ligands with various substituents in 3- or 5- position,3-(4-pyridyl)-5-methyl-pyrazole (L4-m), 3-(4-pyridyl)-5-phenyl-pyrazole (L4-b),3,5-bis(2-pyridyl)-pyrazole (L2-2), 3,5-bis(3-pyridyl)-pyrazole (L3-3),3,5-bis(4-pyridyl)-pyrazole (L4-4), 3-(3-pyridyl)-5-(4-pyridyl)-pyrazole (L3-4), weresynthesized and characterized by IR spectrum and X-Ray diffraction. Hydrogen bonding wasexploited in the crystal form of these ligands.In chapter 3, twelve kinds of complexes (1-12), from 0D, 1D, 2D to 3D, fromnon-interpenetration, 2-fold interpenetration to 3D polyknotting, were obtained successfullyunder hydro(solvo)thermal conditions using L2-2,L3-3,L3-4 and L4-4 as ligands, halogen,pseudohalogen with various coordination geometry as counterion and bridging-ligands. In thesecomplexes, the coordination modes of L ligands and copper(â… ) atoms are similar, and they consist of a motif [Cu₂L]₈. These polyknotting structures can be considered that they are based on 2-foldinterpenetrating network which are connected by linkers. As a result, a strategy to constructpolyknotting polymer were presented through pre-designed ligands with special coordination andappropriate bridging ligands.In chapter 4, nine kinds of complexes (13-21) were obtained from L4-m,L4-b and L4-4under hydro(solvo)thermal conditions. Reactions of L4-m, L4-b and CuI were synthesized underdifferent conditions, complexes 13-17. Except that 13 is a bi-nulcear of Cu₂I₂ coordinated byL4-m from pyridyl-N atoms, 14-17 consist of tri-nuclear copper(â… )-pyrazolated clusters through[CuI]_n, units connecting these clusters. Moreover the tri-nuclear copper(â… )-pyrazolated clusterdisplays the character of tripte-helicate. 18-21 were obtained from L4-4 as ligands and Cu(BF₄)₂,Cu(NO₃)₂, Cu(ClO₄)₂ as copper source under solvothermal conditions. On that conditionscopper(â…¡) was reduced to copper (â… ) and a novel bis(triple-helicates)pentanuclearcopper(â… )-pyrazolated cluster constructed by six pyrazole ligands edge-bridging five copper(â… )atoms formed, which are scarcely countered in coordination chemistry. These clusters arecoordinated to copper(â… ) atoms from pyridyl-N atoms on the periphery of cluster, resulting incoordination polymers constructed by pentanuclear copper(â… )-pyrazolated clusters as SBUs,which offer a strategy to design 3D topology networks with high connectivity.