H2O2/NaHCO3-mediated enantioselective epoxidation of olefins in NTf2-based ionic liquids and under ultrasound

This first example of ultrasonic asymmetric catalysis in ionic liquids clearly proves that the mechanism involves the porphyrin catalyst rather than the classical bicarbonate-activated peroxide (BAP). [Display omitted] ► Optimization of ionic liquids syntheses in terms of green chemistry. ► Environmentally benign H2O2/NaHCO3 combination used for enantioselective epoxidation of olefins. ► Ultrasound/ionic liquids combination prevents the bleaching of Mn catalyst. ► Mechanism for olefins epoxidation catalyzed by Mn-porphyrin in ionic liquid under ultrasound. The bicarbonate-activated peroxide (BAP) system has been shown to constitute an excellent and versatile combination for the epoxidation of olefins. Herein, we demonstrate that the benign H2O2/NaHCO3 oxidative combination can be used for the enantioselective epoxidation of olefins using a chiral manganese porphyrin as a catalyst. This unprecedented result was made possible by the use of an ionic liquid with ultrasound, which leads to the activation of Mn-porphyrin catalysis.