Highly Enantioselective Organocatalytic Carbonyl‐Ene Reaction with Strongly Acidic, Chiral Brønsted Acids as Efficient Catalysts

Abstract

You can count on the counterion in ion-pair intermediates to induce high levels of asymmetry in the title reaction. The efficient transformation proceeds under mild reaction conditions in the presence of an air-stable N-triflylphosphoramide in a low catalyst loading of just 1 mol % to give substituted α-hydroxyesters in good yields and with excellent ee values (see scheme; R=aryl).