Organocatalytic Asymmetric Michael Addition of Oxindoles to Nitroolefins for the Synthesis of 2,2-Disubstituted Oxindoles Bearing Adjacent Quaternary and Tertiary Stereocenters
2016-02-20T03:12:57Z (GMT) by
A bifunctional thiourea-catalyzed Michael addition of activated indolin-3-ones to nitroolefins has been developed. The synthetically useful 2,2-disubstituted indolin-3-one derivatives with vicinal chiral quaternary–tertiary stereocenters were obtained in high yields with excellent stereoselectivities. The adduct can be readily transformed into a structurally interesting heterocyclic architecture by means of further synthetic elaboration.