One-dimensional coordination polymers: Cu(II) and Zn(II) complexes of N-(2-pyridylmethyl)-glycine and N-(2-pyridylmethyl)-l-alanine

The crystal structures of three Cu(II) and one Zn(II) complexes of N-(2-pyridylmethyl)-l-glycine (Hpgly) and N-(2-pyridylmethyl)-l-alanine (Hpala) have been described. They are [Cu(pgly)Cl] · H2O (1), [Cu(pala)Cl] · H2O (2), [Cu(pala)(CH3COO)] · 0.75H2O (3), and [Zn(pgly)(NO3)] (4). All these compounds have 1D polymeric structures in the solid state. In 1 and 2, the chloride ions bridge [Cu(pgly)] and [Cu(pala)] fragments, respectively, to generate 1D polymers while the bridging acetate ligands are responsible for the formation of ΛΔΛΔ type spiral polymers in 3. The nitrate ion in 4 is only acting as a terminal ligand while the carboxylate oxygen atom of the pala ligand bridges the Zn(II) centers to form the zigzag coordination polymeric chain. The 1D coordination polymers in 1 and 2 have very similar arrangements although crystallized in different space groups, and host 1D water chains in their crystal lattices.