Synthesis, Characterization and Crystal Structure of Zn(II) and Cd(II) One- and Two-Dimensional Coordination Polymers Derived from Pyridine Based Schiff Base ligand

Abstract

Four coordination polymers with the formulas [Zn(L)(NO3)]n (1), {[Zn(L)(NO2)]·CH3OH}n (2), [Cd(L)(NO2)]n (3) and [Cd(L)(NO3)]n (4) {HL=2-benzolypyridine-isonicotinoylhydrazone (HBPIH)} have been synthesized and characterized by elemental analyses, FT-IR spectroscopy, 1H and 13C NMR and single crystal X-ray data diffraction. The L ligand acts as a negatively charged tetradentae N3O-donor in 1–3 and pentadentate ligand in 4. The Schiff base ligand coordinates to a metal center as N2O-donor and coordinates to adjacent metal center via its Para-Nitrogen of pyridlyl group in 1–3 leading to formation of one-dimensional, 1D, coordination polymer. The oxygen atom of the ligand L also coordinates to the third metal center as a bridging atom in 4 and forms a two-dimensional, 2D, coordination polymer. Metal centers are six coordinated with distorted octahedral geometry in 1–3 and seven coordinated with pentagonal bipyramid geometry in 4. The nitrate and nitrite groups act as asymmetric bidentate ligands in all complexes.