Estudo cristalográfico de compostos de platina(II) e de níquel(II) com ditiocarbimato

Abstract

Dithiocarbamate salts and its complexes are well known because of their wide range of applications. For example, dithiocarbamate and derivatives are very active accelerators in rubber vulcanization. Many dithiocarbamates, anions and complexes, show biological activity and are used as fungicides and bactericides. Besides being less investigated, interest in the synthesis and characterization of dithiocarbimate metal complexes is due to their similarity with dithiocarbamates. The nickel(II) and platinum(II) bisditiocarbimate complexes are necessarily anionic species. Thus, the use of active counter ions could improve their biological activity. In the present work, the structural elucidation, by X-ray diffraction, is presented of two novel platinum(II) and three novel nickel(II) compounds with the R-ditiocarbimate anion: tetra-n-butylammonium bis(2,5-dichlorophenylsulphonyldithiocarbimato) nickelate(II) (NIDBU), tetra-n-butylammonium bis(4-iodophenylsulphonyldithio carbimato)nickelate(II) (NIBBU), tetra-n-butylammonium bis(ethylsulphonyldithio carbimato)nickelate(II) (NIJBU), tetra-n-butylammonium bis(phenylsulphonyldithio carbimato)platinate(II) (PTB) and tetra-n-butylammonium bis(4-bromophenyl sulphonyldithiocarbimato)platinate(II) (PT2F1). The compounds studied are constituted by two tetra-n-butylammonium cations and one complex anion. The metallic atom is coordinated by 4 sulfur atoms of two R-sulfonyldithiocarbimato ligands, in a distorted square-planar configuration. With the exception of NIBBU, in all other compounds the metallic atom crystallizes in an inversion center. The complex anion geometry mainly depends on the R group of the R-sulfonyldithiocarbimato ligand. The crystal packing of the 5 compounds presents weak interactions as Csp3-H...X (X = O, N e/ou S e Cl) between the cátion and the complex anion.