Trans-Dibromotetrakis(dimethyl sulfoxide)ruthenium(II): A versatile starting material for the synthesis of ruthenium(II) complexes for use as molecular oxygen oxidation catalysts

Abstract

The synthesis of neutral ruthenium(II) dihalo complexes of the type RuX 2(Me 2SO) 3L and RuX 2(L′) 4, using the easily prepared RuBr 2(Me 2SO) 4 complex is described. The synthesis of Ru(II) complexes of the type where L is a phoshine or arsine yields materials that are very active catalysts for the molecular oxygen oxidation of thioethers to sulfoxides. The new complexes are characterized via elemental analyses, 1H NMR spectra, electronic spectra, their E 1 2 values (determined by cyclic voltammetry), and by their catalytic activity for the oxygen oxidation of thioethers to sulfoxides.