Osmium(IV) thiocarbamide complexes. Synthesis and crystal and molecular structures of [Os(Thio)2Cl4]. 2H2O

Tetrachlorobis(thiocarbamide)osmium(IV) dehydrate, [Os(Thio) 2Cl4]. 2H2O, was synthesized by the reaction of K2[OsO2(OH)4] with thiocarbamide in 6 M HCl. The compound was characterized by chemical analysis and IR, UV, and X-ray photoelectron spectroscopies. The structure was determined by X-ray diffraction analysis. The coordination polyhedron of the osmium atom lying in the axis 2 is a distorted cis-octahedron formed by four chlorine atoms and two sulfur atoms of two monodentate thiocarbamide ligands: Os-S 2.3075(18) Å and Os-Cl 2.3625(18) Å (trans to Cl) and 2.4294(19) Å (trans to S). The conditions for the formation of the osmium(IV) thiocarbamide complexes in HCl solutions were determined using spectrophotometry, and the spectral characteristics of [Os(Thio)Cl5]-were obtained. © Pleiades Publishing, Ltd., 2010.