Synthesis and study of -substituted methylthio derivatives of cobalt bis(dicarbollide).

The -methylthio derivatives of cobalt bis(dicarbollide) were synthesized by reaction of anhydrous CoCl with -carborane [7-MeS-7,8-CBH] and isolated as a mixture of -[1,1'-(MeS)-3,3'-Co(1,2-CBH)] and -[1,2'-(MeS)-3,3'-Co(1,2-CBH)] isomers. The structures of both isomers were studied using DFT quantum chemical calculations. The most preferable geometry of rotamers and the stabilization energy of -methylthio derivatives of cobalt bis(dicarbolide) were calculated. The (BEDT-TTF)[1,1'-(MeS)-3,3'-Co(1,2-CBH)] salt was prepared and its structure was determined by single crystal X-ray diffraction. The cisoid conformation of the -[1,1'-(MeS)-3,3'-Co(1,2-CBH)] anion is stabilized by short intramolecular CH⋯S hydrogen and BH⋯S chalcogen bonds between the dicarbollide ligands, that is in good agreement with the data of quantum chemical calculations.