Synthesis and Crystal Structure of Complex [Zn(BCBI)_2(H_2O)_4]·2H_2O

Complex [Zn(BCBI)2(H2O)4]·2H2O(1) was synthesized by reaction of 1,3-bis-carboxymethyl-benzimidazole(H2BCBI) with zinc chloride in an aqueous solution of methanol by solvent evaporation method.The structure was characterized by IR,elemental analysis and X-ray single crystal diffraction.1 belongs to triclinic system,space group P-1 with a=7.400 9(15),b=9.4066(19),c=9.6559(19),α=81.58(3)°,β=75.97(3)°,γ=78.08(3)°,V=634.8(2)3,Z=1,Dc=1.674 mg·cm-3,μ=1.050 mm-1,S=1.023.Zn(Ⅱ) in 1 is coordinated with four water molecules and two monodentate H2BCBI ligands in a slightly distorted octahedral geometry.The crystal structure is stabilized by intermolecular O-H┈O hydrogen bonds and the aromatic weak π-π packing interactions,which extended 1 into a three-dimensional open framework,which is important for stabilizing the structure.