Highly Enantioselective Michael Addition of 3-Aryloxindoles to Phenyl Vinyl Sulfone Catalyzed by Cinchona Alkaloid-Derived Bifunctional Amine-Thiourea Catalysts Bearing Sulfonamide as Multiple Hydrogen-Bonding Donors

A highly enantioselective Michael addition of 3-aryloxindole to phenyl vinyl sulfone catalyzed by a quinine-derived bifunctional amine-thiourea-bearing sulfonamide as multiple hydrogen-bonding donor catalyst has been investigated. The corresponding adducts, which contain a chiral quaternary carbon center at the 3-position of the oxindole, were obtained in moderate-to-good yields (52-86%) with high-to-excellent enantioselectivities (83-98% ee).