Synthesis, spectroscopic and magnetic properties of nickel(II) with N-protected amino acids: crystal and molecular structure of bis(N-acetylglycinato)tetraaquonickel(II)

Abstract

Nickel(II) complexes of the general formula NiL 2· nH 2O have been prepared with various N-protected amino acids and characterized by thermogravimetric, magnetic susceptibility, IR and UV spectroscopy. The crystal structure of bis(N-acetylglycinato) tetraaquonickel(II) has been determined. The coordination around nickel is octahedral with two acetylglycine ligands trans to each other. Acetylglycine coordinates with nickel through a single oxygen of the carboxylate group, and the remaining four coordination sites are occupied by four water molecules. The structure is held together by strong intermolecular hydrogen bonding. Spectroscopic studies indicate that all complexes are octahedral in structure.