title: Asymmetric Michael addition reaction of 3-substituted-N-Boc oxindoles to activated terminal alkenes catalyzed by a bifunctional tertiary-amine thiourea catalyst.
abstract: The current article reports an organocatalytic strategy for the asymmetric catalysis of chiral oxindoles bearing 3-position all-carbon quaternary stereocenters. Accordingly, highly enantioselective Michael addition reactions of 3-substituted oxindoles to terminal alkenes have been developed by utilizing a bifunctional tertiary-amine thiourea catalyst. The reactions accommodate a number of Michael donor compounds (different substituted 3-aryl or methyl oxindoles), and Michael acceptor compounds (vinyl ketones and vinyl sulfones) to give the desired oxindole products with moderate to excellent yields (up to 99%) and moderate to excellent enantioselectivities (up to 91% ee).
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Xi
authors.forename: Sanzhong
authors.initials: S
authors.lastname: Luo
authors.forename: Jin-Pei
authors.initials: JP
authors.lastname: Cheng