title: Asymmetric Friedel-Crafts alkylation of α-substituted β-nitroacrylates: access to β(2,2)-amino acids bearing indolic all-carbon quaternary stereocenters.
abstract: A highly enantioselective Friedel-Crafts alkylation reaction of indoles with acyclic α-substituted β-nitroacrylates is developed under the catalysis of Ni(ClO4)2-bisoxazoline complex at 1 mol % catalyst loading, affording chiral indolic β-nitroesters bearing all-carbon quaternary stereocenters in excellent yields and ees of up to 97%. Transformation of one of the products to β(2,2)-amino ester and tetrahydro-β-carboline through nitro reduction and sequential Pictet-Spengler cyclization was exemplified.
authors.affiliation: College of Chemical Engineering and Material Sciences, Zhejiang University of Technology , Chaowang Road 18#, Hangzhou310014, China.
authors.forename: Jian-Quan
authors.initials: JQ
authors.lastname: Weng
authors.forename: Qiao-Man
authors.initials: QM
authors.lastname: Deng
authors.forename: Liang
authors.initials: L
authors.lastname: Wu
authors.forename: Kai
authors.initials: K
authors.lastname: Xu
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.forename: Ren-Rong
authors.initials: RR
authors.lastname: Liu
authors.forename: Jian-Rong
authors.initials: JR
authors.lastname: Gao
authors.forename: Yi-Xia
authors.initials: YX
authors.lastname: Jia
mesh_terms: D000478:Alkylation; D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry*; D003500:Cyclization; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D009574:Nitro Compounds / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D056831:Coordination Complexes; D007211:Indoles; D009574:Nitro Compounds; D002244:Carbon; D009532:Nickel