Synthesis and Crystal Structure Determination of a Nickel(II) Complex of an Acyclic Pentadentate (N5) Mono Schiff Base Ligand

The asymmetrical tripodal tetraamine ligand N[(CH2)3NH2]2[(CH2)2NH2] (ppe) was condensed with 2-acetylpyridine in the presence of nickel(II) ion. In ethanolwater solution the reaction stops after the first stage of condensation, and a new nickel(II) complex of an acyclic pentadentate (N5) mono Schiff base ligand was obtained. X-ray structure analysis of the resulting complex, [Ni(ppe-py)(H2O)](ClO4)2, indicates that condensation with 2-acetylpyridine is at the propylene chain of ppe. The geometry around the nickel ion is distorted octahedral in which the sixth co-ordination group is a solvent molecule.