New ligands for manganese catalysed selective oxidation of sulfides to sulfoxides with hydrogen peroxide

In situ prepared manganese complexes with ligands 1–5 have been used in the catalytic oxidation of sulfides to sulfoxides using hydrogen peroxide at 0°C in acetone. Using ligand 4, methyl phenyl sulfoxide is obtained in 55% yield and turnover numbers up to 250, while the formation of sulfone is almost suppressed.