Extended Network via π……π Interaction and Hydrogen Bond Linkages of 1D Copper（Ⅱ）Coordination Polymer： Synthesis, Crystal Structure and Characterization of Cu（4,4‘’—bpy）（2—pzc）—（H2O

摘要

A penta-coordinated CU(Ⅱ） complex with mixed ligands 4,4''-bipyridine(4,4''-bpy) and 2-pyrazine-5-carboxylate anion(2-pzc),[Cu(4,4''-bpy)(2-pzc) (H2O)]ClO4·H2O(1),has been solvothermally synthesized and characterized.Complex 1 crystallizes in the monoclinic space group P21 with a=0.82996(2)nm,b=1.58156(5)nm,c=1.53873(1)nm,β=103.536(2)°,V=1.96322(8)nm3,Mr=478.30,z=4,Dc=1.618g/cm3,final R=0.0544 and wR=0.1487,The Structure of 1 indicates that the central Cu(Ⅱ） atom is penta-cooridinated by two N atoms from two 4,4''-bpy ligands,and one Natom and one oxygen atom of the 2-pzc ligand in the equatorial plane,and one oxygen atom of the coordinated water molecule at the axial position.The coordination geometry of Cu(Ⅱ） atom could be considered as a slightly distorted square-pyramidal environment.The 4,4''-bpy ligands bridge the Cu(Ⅱ） centers to form a one-dimensional chain,and 2-pzc acts as a terminal chelated ligand,and π……π interaction between the pyrazine rings of 2-pzc ligands of adjacent chains links the chains into a 2D sheet.Furthermore,the hydrogen bonds among the oxygen atoms of the uncoordinated water molecules and the N atoms and O atoms of 2-pzc ligands and the oxygen atoms of the coordinated water molecules link the sheets into the ultimate 3D network of complex 1.