Trans-Bis(Saccharinato)zinc and -Cadmium Complexes with N-(2-Aminoethyl)piperazine: Synthesis, Crystal Structures and IR Spectra

Abstract

The reactions of N-(2-aminoethyl)piperazine (aeppz) with tetraaqua-bis(saccharinato)zinc(II) and -cadmium(II) in ethanol solution yield the new complexes trans-[Zn(sac)<inf>2</inf>(aeppz)<inf>2</inf>] (1), and trans-[Cd(sac)<inf>2</inf>(aeppz)<inf>2</inf>] (2) (sac = saccharinate), respectively. The complexes were characterized by elemental analyses, IR spectroscopy and X-ray crystallography. Both complexes 1 and 2 are mononuclear of Q symmetry. The zinc(II) and cadmium(II) ions are coordinated by two neutral aeppz ligands and two sac anions in an elongated distorted octahedral environment. The aeppz ligand acts as a bidentate N, N' donor through the central heterocyclic N atom and the N atom of the aminoethyl group, while the sac ligand is O-coordinated via the carbonyl O atom. The packing of the molecules in the crystals in both complexes is consolidated by arene π - π stacking interactions between the sac rings and by intermolecular hydrogen bonds involving the amine groups of aeppz and the sulfonyl oxygen atoms of the sac ligands. © 2005 Verlag der Zeitschrift für Naturforschung.