Stereocontrolled Creation of All-Carbon Quaternary Stereocenters by Organocatalytic Conjugate Addition of Oxindoles to Vinyl Sulfone

Multifunctional catalysts in operation: A novel class of trifunctional thiourea catalysts containing natural amino acid residues have been prepared (see scheme), and found to be very effective towards the asymmetric addition of 3‐alkyl‐oxindoles to 1,1‐bis(benzenesulfonyl)ethylene. This synthetic protocol has led to the enantioselective synthesis of 3‐alkyl‐3‐aryl‐disubstituted oxindoles and indolines with an all‐carbon quaternary stereogenic center.