Spectral and structural studies of Zn and Cd complexes of 2-pyridineformamide N(4)-ethylthiosemicarbazone

• Published in: Polyhedron Vol. 23; no. 14; pp. 2303 - 2313
• Main Authors: Bermejo, Elena, Castiñeiras, Alfonso, Fostiak, Larissa M., Santos, Isabel Garcı́a, Swearingen, John K., West, Douglas X.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 09.09.2004
• Subjects: 2-pyridineformamide; Cadmium; Crystal structure; Thiosemicarbazone; Zinc; Cadmium; Thiosemicarbazone; 2-pyridineformamide; Zinc; Crystal structure
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2004.07.010

Zn(II) and Cd(II) complexes of 2-pyridineformamide N(4)-ethylthiosemicarbazone have been synthesized and characterized using physical and spectral methods. X-ray structure analysis of the complexes [Zn(Am4E)(OAc)] 2, [Zn(HAm4E)I 2], [Cd(Am4E) 2], [Cd(HAm4E)Br 2] · DMSO and [Cd(HAm4E)I 2] · DMSO, as representative species, has authenticated that coordination is via the pyridyl nitrogen, imine nitrogen and thione or hiolato sulphur atoms when coordinating as the neutral and anionic ligand, respectively. Reduction of 2-cyanopyridine in the presence of N(4)-ethylthiosemicarbazide produces 2-pyridineformamide N(4)-ethylthiosemicarbazone, HAm4E. Complexes with various zinc(II) and cadmium(II) salts have been prepared and characterized using physical and spectral methods. In addition, the crystal and molecular structure of [Zn(Am4E)(OAc)] 2 ( 1), [Zn(HAm4E)I 2] ( 4a), [Cd(Am4E) 2] ( 5a), [Cd(HAm4E)Br 2] · DMSO ( 7a) and [Cd(HAm4E)I 2] · DMSO ( 8a) have been obtained. Coordination is via the pyridyl nitrogen, imine nitrogen and thione or thiolato sulfur when coordinating as the neutral and anionic ligand, respectively. [Zn(Am4E)(OAc)] 2 is the first example of a binuclear complex with a 2-pyridineformamide thiosemicarbazonato ligand in which the two acetate bridging groups are equivalent resulting in a center of symmetry.