title: Squaramide-catalysed asymmetric cascade aza-Michael/Michael addition reaction for the synthesis of chiral trisubstituted pyrrolidines.
abstract: A bifunctional squaramide catalysed aza-Michael/Michael cascade reaction between nitroalkenes and tosylaminomethyl enones or enoates has been developed. This organocatalytic cascade reaction provides easy access to highly functionalized chiral pyrrolidines with a broad substrate scope, giving the desired products in good yields (up to 99%) with good diastereoselectivities (up to 91 : 9 dr) and excellent enantioselectivities (up to >99% ee) under mild conditions. This protocol provides a straightforward entry to highly functionalized chiral trisubstituted pyrrolidine derivatives from simple starting materials.
authors.affiliation: School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China. dudm@bit.edu.cn.
authors.forename: Bo-Liang
authors.initials: BL
authors.lastname: Zhao
authors.affiliation: School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China. dudm@bit.edu.cn.
authors.forename: Ye
authors.initials: Y
authors.lastname: Lin
authors.affiliation: School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China. dudm@bit.edu.cn.
authors.forename: Hao-Hao
authors.initials: HH
authors.lastname: Yan
authors.affiliation: School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing 100081, People's Republic of China. dudm@bit.edu.cn and State Key Laboratory of Elemento-Organic Chemistry, Nankai University.
authors.forename: Da-Ming
authors.initials: DM
authors.lastname: Du