THE COORDINATION CHEMISTRY OF (2-THIAZOLIN-2-YL)HYDRAZINE HYDROCHLORIDE (TZHYHCL) .1. CRYSTAL-STRUCTURE OF THE LIGAND AND STUDY OF ITS INTERACTION WITH NICKEL(II)

The crystal structure of (2-thiazolin-2-yl)hydrazine hydrochloride (Tz HyHCl) is reported, together with its coordination behaviour and equil ibria study with nickel(II) in aqueous solution at 298 K and 0.1 M ion ic strength in NaC1O(4). The formation constants are determined and di scussed in terms of the characteristics of the ligand. The compound di aquabis [(2-thiazolin-2-yl)hydrazine] nickel(II) chloride dihydrate ha s been isolated and its crystal and molecular structure determined by X-ray analysis. The complex cation shows a distorted octahedral struct ure with the nickel atom situated in an inversion centre and coordinat ed to two water molecules [Ni-O(1) = 2.090(2) Angstrom], two thiazolin ic nitrogens [Ni-N(1) = 2.027(3) Angstrom] and two terminal hydrazinic nitrogens [Ni-N(3) = 2.156(2) Angstrom]. A hydrogen bond scheme is pr esent in the structure interlinking TzHy ligands, water molecules and chloride ions.