Syntheses, structures, and properties of zinc(II) and copper(II) coordination polymers with imidazole-containing ligands

The reactions of Zn(NO3)(2)center dot 6H(2)O/CuCl2 center dot 2H(2)O and 1,4-bis(1-imidazolyl)benzene (bib)/1,4-bis(1-imidazol-1-ylmethyl)benzene (biyb), carried out under hydrothermal conditions, produced two new coordination polymers [Zn(bib)(HCOO)(2)center dot H2O] (1) and [Cu(biyb)Cl-2] (2), respectively, which were characterized by elemental analysis, infrared spectroscopy, thermogravimetric analyses, and single-crystal X-ray diffraction. In complex 1, the Zn-II centers are bridged by bib ligands to form a chain, where the adjacent chains are condensed by strong intermolecular O-H center dot center dot center dot O hydrogen-bonding and aromatic pi-pi stacking interactions to generate a 3D supramolecular structure. In 2, the Cu-II centers are bridged by biyb ligands to form, again, chains through C-H center dot center dot center dot Cl hydrogen bonds, and these adjacent chains with different orientations are joined to generate a 3D supramolecular structure.