Synthesis and structural characterization of thiolato-bridged zinc(II) complexes with NNS-tridentate thiolic ligands

Zinc(II) complexes with 2-[(2-aminoethyl)amino]ethanethiol (HL1), 2-[(3-aminopropyl)amino]ethanethiol (HL2), 2-[(2-pyridylmethyl)amino]ethanethiol (HL3), and 2-{[2-(2-pyridyl)ethyl]amino}ethanethiol (HL4), [Zn(L-1)](ClO4) (1), [Zn{Zn(L-1)(2)}(2)](ClO4)(2) (2), [Zn(L-2)](ClO4) (3), [Zn{Zn(L-3)(2)}(2)](ClO4)(2) (4), and [Zn-3(L-4)(3)](ClO4)(3) (5), have been synthesized and characterized by measurements of the infrared and electronic spectra. The molecular structures of these complexes were determined by the single-crystal X-ray structure analysis, Complex 1 has a thiolato-bridged polymeric chain structure, in which each metal atom is essentially four-coordinated in a distorted tetrahedron. Complexes 2 and 4 have a thiolato-bridged trinuclear complex with a linear arrangement of three metal atoms. Complex 5 is a thiolato-bridged trinuclear complex displaying a six-membered ring of Zn3S3.