title: Cinchona alkaloid squaramide catalyzed enantioselective hydrazination/cyclization cascade reaction of α-isocyanoacetates and azodicarboxylates: synthesis of optically active 1,2,4-triazolines.
abstract: An efficient enantioselective hydrazination/cyclization cascade reaction of α-substituted isocyanoacetates to azodicarboxylates catalyzed by Cinchona alkaloid derived squaramide catalysts has been investigated, affording the optically active 1,2,4-triazolines in excellent yields (up to 99%) and good to excellent enantioselectivities (up to 97% ee) under mild conditions.
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, People's Republic of China.
authors.forename: Mei-Xin
authors.initials: MX
authors.lastname: Zhao
authors.forename: Hong-Lei
authors.initials: HL
authors.lastname: Bi
authors.forename: Hao
authors.initials: H
authors.lastname: Zhou
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.forename: Min
authors.initials: M
authors.lastname: Shi
mesh_terms: D000085:Acetates / Q000737:chemistry*; D000577:Amides / Q000737:chemistry*; D001391:Azo Compounds / Q000737:chemistry; D002384:Catalysis; D002930:Cinchona Alkaloids / Q000737:chemistry*; D003500:Cyclization; D003998:Dicarboxylic Acids / Q000737:chemistry*; D017953:Isocyanates / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D014230:Triazoles / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000085:Acetates; D000577:Amides; D001391:Azo Compounds; D002930:Cinchona Alkaloids; D003998:Dicarboxylic Acids; D017953:Isocyanates; D014230:Triazoles