New chiral molybdenum complex catalyzed sulfide oxidation with hydrogen peroxide

► Six new chiral cis-dioxoMo(VI) complexes have been synthesized and characterized. ► The Complexes are studied for catalytic chiral sulfoxidation reactions with H2O2. ► Formation of oxoperoxoMo(VI) complexes during catalytic cycle was observed. ► Reactions resulted good to moderate ee with high yield of sulfoxide. ► Bulky substituent at specific position of the catalysts influences ee.