Structural characterization of a thiazoline-pyrazole ligand and its complexes with cobalt(II) and copper(II)

The structural characterization of 2-(pyrazol-1-yl)-2-thiazoline (PyTn) is reported. The complexes dichlorobis[2-(pyrazol-l-yl-kappa N)-2thiazoline-kappa N] cobalt(II)-water- (1/2) (1) and di-mu-chloro-bis{chloro(2-(pyrazol-1-yl-kappa N) -2-thiazoline-kappa N]}copper(II) (2) have been isolated and characterized through elemental analysis, IR, UV-Vis-NIR diffuse reflectance, X-ray diffraction and magnetic susceptibility, as well as, in the case of 2, by means of EPR. The environment around cobalt atom in I may be described as a distorted octahedron with the metallic atom coordinated to two thiazoline nitrogen atoms [Co-N(1) = 2.097(2) angstrom], two pyrazole nitrogen atoms (CoN(3) = 2.157(2) angstrom] and two chloride ions [Co-Cl(1) = 2.472(1) angstrom]. With regard to 2, it can be said that its structure consists of dimeric [Cu2Cl4L2] molecules in which copper ions are bridged by two chloro ligands. The geometry about each copper ion approximates to a distorted square pyramid with each copper atom coordinated to one thiazoline nitrogen atom [Cu-N(1) = 2.012(2) angstrom], one pyrazole nitrogen atom [Cu-N(3) = 1.995(2) angstrom], one terminal chloro ligand [Cu-Cl(1) = 2.254(1) angstrom] and two bridging chloro ligands [Cu-Cl(2) = 2.218(1) angstrom, Cu-Cl(2a) = 2.906(1) angstrom]. (c) 2005 Elsevier Ltd. All rights reserved.