title: Cinchona Alkaloid Squaramide-Catalyzed Asymmetric Michael Addition of α-Aryl Isocyanoacetates to β-Trifluoromethylated Enones and Its Applications in the Synthesis of Chiral β-Trifluoromethylated Pyrrolines.
abstract: Cinchona alkaloid squaramide can effectively catalyze the asymmetric Michael addition of α-aryl isocyanoacetates to β-trifluoromethylated enones, affording the corresponding adducts with an adjacent chiral tertiary carbon center bearing a CF3 group and a quaternary carbon center in moderate to good yields along with excellent stereoselectivities. The adduct can be easily transformed into biologically attractive chiral β-trifluoromethylated pyrroline carboxylate in high yield via an isocyano group hydrolysis/cyclization/dehydration cascade reaction by treating with acid. The one-pot enantioselective Michael addition/isocyano group hydrolysis/cyclization/dehydration sequential protocol has also been investigated.
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology , 130 Mei Long Road, Shanghai 200237, China.|CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Mei-Xin
authors.initials: MX
authors.lastname: Zhao
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology , 130 Mei Long Road, Shanghai 200237, China.
authors.forename: Hui-Kai
authors.initials: HK
authors.lastname: Zhu
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology , 130 Mei Long Road, Shanghai 200237, China.
authors.forename: Tong-Lei
authors.initials: TL
authors.lastname: Dai
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology , 130 Mei Long Road, Shanghai 200237, China.|State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 354 Fenglin Road, Shanghai 200032, China.
authors.forename: Min
authors.initials: M
authors.lastname: Shi