Flexible Nitrogen Ligand To Build A Functional Complex Design, Synthesis And Performance Research

In this paper, we select one 1-D complex containing Cu(II) as a precursor complex, two offspring complexes are obtained via the substitution, addition or recombination reactions. Furthermore, their syntheses, structural analysis, and catalytic behaviors are also studied. In addition, using bis-benzimidazole and bis-benzotriazole derivatives as building block, we obtain two new complexes and also investigate their syntheses andstructural analysis.In the first part of this paper, we select one 1-D complex containing the facile leaving groups and coordinatively unsaturated metal ions{[Cu(bbbm)(CH₃COO)₂]·(CH₃OH)₂}_n [bbbm=1,1'-(1,4-butanediyl)bis-1H-benzimidazole)] as a precursor complex (Q), two offspring complexes [Cu(bbbm)(N₃)₂(Py)]_n (1) and [Cu₂(bbbm)₂(SCN)₄(CH₃OH)₂] (2) were obtained via the substitution, addition or recombination reactions. The precursor complexes with specific, relatively steady the structural integrity can react with organic ligands thought directional self-assembly at moderate condition, and the "genes" of precursor complexes can be maintained from precursors to their offspring complexes. But during the synthesis, the severe condition, such as reaction temperature, can have an strong influence on, even can change the structure of their offspring complexes. As anticipated, the offspring complex 1 maintain the "genes" of precursor complexes, both are infinitely extended 1D chains structure. Whereas during the synthesis of the offspring complex 2, the high reaction temperature brings on recombination reaction of the precursor, result in the formation of the discrete binuclear structure of the offspring complex 2. It states that we can design appropriate the precursor complexes, and then the offspring complexes by controlling the number of leaving groups in precursor complexes via the substitution, addition or recombination reactions. In addition, their catalytic abilities are investigated in detail on the oxidative couplings of 2,6-dimethylphenol (DMP) by using H₂O₂ (30 mass%) as an oxidant and the polyphenol oxidation reactivity. The result of catalysis for the oxidative couplings of 2,6-dimethylphenol (DMP) displays the precursor are obvious higher efficient catalysts than their offspring complexes. It is found that coordination environment of metal copper in complexes may be responsible for their catalytic behaviors. The catalysts of the precursor complex (Q) and the offspring complexes 1 and 2 also validate our prediction. The result of catalysis for the polyphenol oxidation reactivity shows catalytic activity of three complexes is poor.In the second part, to explore how flexible ligands influence on structure of the complexes, we chose two structurally related mufti-haptoes ligands 1,1'-(1,4-butanediyl)bis-1H-benzimida2ole) (bbbm), and 1,1'-(1,3-propylene)-bis-2H-benzotriazole (2-pbbt) as building block. By the assembling of the above ligands with metal salts, two metal-organic complexes [Hg(bbbm)(H₂edta)(H₂O)]·2CH₃OH (3) and [Cu(I)₂(2-pbbt)₂Cl₂] (4) have been obtained at room temperature. The single crystal X-ray diffraction shows complexes 3 and 4 are discrete binuclear structure. During the synthesis of the complex 4, The valence of copper ions change from Cu(II) in CuCl₂ to Cu(I) in the complex 4.