Synthesis, crystal structures and magnetic properties of two new nickel(II) complexes with alpha-amino acid Schiff base

Two nickel(II) complexes [Ni(napgly)(MeOH)](n) (1) and [Ni(napphe)(H2O)(2)(MeOH)] H2O (2), where the tridentate Schiff-base ligands H(2)napgly and H(2)napphe are condensed from 2-hydroxyl-1-naphthaldehyde with glycine and L-phenylalanine, respectively, were prepared and structurally characterized. In 1, two inversion-related Ni(II) ions were bridged by two O atoms from the phenolate groups of two napgly anions, forming a centrosymmetric dimeric unit which was further linked by carboxylate groups to give a two-dimensional network. Magnetic susceptibility studies performed on the complex revealed anti-ferromagnetic coupling between the metal centers. In 2, the crystal structures of the complex displayed a distorted octahedral coordination geometry in which the ONO-donor Schiff base was bonded to the metal. Intermolecular H-bonds linked the compound into a 2-D layer structure.