Synthesis and physic-chemical properties of a copper(II) complex with 2-(2-pyridyl)iminotetrahydro-1,3-thiazine hydrochloride-water (1/2) (PyTzHCl.2H2O). Crystal structure of PyTz and [[CuCl(PyTz)]2(mu-Cl)2]

Abstract

The synthesis of 2-(2-pyridyl)iminotetrahydro-1,3-thiazine (PyTz) has been carried out, as well as the determination of its X-ray crystal structure, together with the coordination behaviour and equilibra study of PyTzHCl.2H2O with copper(II) in aqueous solution at 298 K and 0.1 M ionic strength in NaClO4. The formation constants are determined and discussed in terms of the characteristics of the ligand. The compound Di-mu-chloro-bis[chloro[2-(2-pyrydil-kappaN)amino-5,6-dihydro-4H-1,3-thiazine-kappaN]copper] has been isolated and its crystal and molecular structure determined by X-ray analysis. The structure consists of dimeric molecules [Cu2Cl4L2], in which copper ions are bridged by two chloro ligands. The geometry about each copper approximates to a distorted square pyramid with the bridging ligands occupying apical and equatorial sites of each copper ion, while the PyTz ligand and the remaining chloride ion are located in an equatorial plane. The compound was also characterized through elemental analysis, magnetic susceptibility, electron paramagnetic resonance, and electronic and infrared spectroscopies.