title: γ'-Selective Functionalization of Cyclic Enones: Construction of a Chiral Quaternary Carbon Center by [4+2] Cycloaddition/Retro-Mannich Reaction with 3-Substituted Maleimides.
abstract: The first example of organocatalyzed γ'-selective functionalization of cyclic enones with 3-substituted maleimides results in the stereoselective construction quaternary carbon center is presented. The reactions provided γ'-functionalized cyclic enones and β-functionalized cyclopentenones in good to excellent yields with excellent diastereo- and enantioselectivities. DFT calculations indicated that the reaction might proceed as a [4+2] cycloaddition/retro-Mannich reaction which could explain the unexpected product with a chiral quaternary carbon center and the excellent stereoselectivity.
authors.affiliation: Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Chuncheng
authors.initials: C
authors.lastname: Zou
authors.affiliation: Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Chuikun
authors.initials: C
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Min
authors.initials: M
authors.lastname: Lu
authors.affiliation: Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Sun
authors.affiliation: Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China. yejx@ecust.edu.cn.
authors.forename: Jinxing
authors.initials: J
authors.lastname: Ye
keywords: DFT calculations; asymmetric catalysis; cycloaddition; isomerization; organocatalysis