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Synthesis and crystal structure of a new tetra-nuclear copper(II) complex based on the Schiff base
Dawei Li1, Wanying Qi1, Jingjing Wang1
1School of Chemistry and Chemical Engineering Henan Engineering Technology Research Center for Green Catalytic and Atom Economic Conversion of Coal-based Benzene Zhengzhou Normal University,Zhengzhou 450044 Henan Province People's Republic of China.
Abstract:
The title complex, bis-{μ4-(E)-2-[(5-meth-oxy-2-oxido-benzyl-idene)amino]-benzoato}bis-{μ2-(E)-2-[(5-meth-oxy-2-oxido-benzyl-idene)amino]-benzoato}tetra-copper(II), [Cu4(C15H11NO4)4] or Cu4(L)4, was synthesized by the solvothermal reaction of (E)-2-[(2-hy-droxy-5-meth-oxy-benzyl-idene)amino]-benzoic acid (H2 L) with copper(II) chloride. It crystallizes in the triclinic system with space group Pī. The tetra-nuclear structure consists of two fully symmetric dinuclear copper moieties. In the dinuclear copper structural unit, both copper(II) metal centers exhibit a five-coordinate NO4 environment. Of the four coordinating oxygen atoms, two are phenolate oxygen atoms acting as bridges from two different ligands, while the other two oxygen atoms are derived from the carboxyl groups of two distinct ligands, respectively. SHAPE analysis indicates that both copper(II) centers adopt a distorted trigonal-bipyramidal (D 3h ) geometry. C-H⋯O hydrogen bonds and C-H⋯π inter-actions contribute to the cohesion of the crystal packing.
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