Zinc(II) and cadmium(II) complexes containing the 2-{2-[3-(triethoxysilyl)-propylthio]ethylamino}ethylamino ligand

The new 2-{2-[3-(triethoxysilyl)propylthio]ethylamino}ethylamino SNN ligand, has been synthesized and fully characterized. Its donor properties towards zinc(II) and cadmium(II) have been investigated in order to simulate the metal uptake behavior in environmental applications. It reacts with ZnX₂ (X = Cl, Br and I) and CdCl₂ to form monomeric molecular complexes, MX₂(SNN)₂. Mass, i.r., ¹H- and ¹³C{¹H}-n.m.r. spectroscopies and elemental analyses reveal that, in these complexes, the metal attains its highest coordination number by linking to two nitrogen atoms of the ethylenediamine portion, and to two halogen atoms. The SNN ligand thus behaves as a bidentate four electrons donor, the thioether sulfur atom still remaining available for further coordination.