title: Cinchona alkaloid squaramide/AgOAc cooperatively catalyzed diastereo- and enantioselective Mannich/cyclization cascade reaction of isocyanoacetates and cyclic trifluoromethyl ketimines.
abstract: An efficient diastereo- and enantioselective Mannich-type/cyclization cascade reaction of α-substituted isocyanoacetates and cyclic trifluoromethyl ketimines cooperatively catalyzed by cinchona alkaloid-derived multi-hydrogen-bonding donor squaramide and AgOAc has been investigated, affording the optically active trifluoromethyl-substituted tetrahydroimidazo[1,5-c]quinazoline derivatives in excellent yields (up to 99%) and good to excellent stereoselectivities (up to >15:1 dr, up to 98% ee) under mild conditions.
authors.affiliation: Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology , Shanghai 200237, P.R. China.
authors.forename: Mei-Xin
authors.initials: MX
authors.lastname: Zhao
authors.forename: Hong-Lei
authors.initials: HL
authors.lastname: Bi
authors.forename: Rong-Hui
authors.initials: RH
authors.lastname: Jiang
authors.forename: Xu-Wei
authors.initials: XW
authors.lastname: Xu
authors.forename: Min
authors.initials: M
authors.lastname: Shi
mesh_terms: D000085:Acetates / Q000737:chemistry*; D002384:Catalysis; D002930:Cinchona Alkaloids / Q000737:chemistry*; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D007097:Imines / Q000737:chemistry*; D015394:Molecular Structure; D009570:Nitriles / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000085:Acetates; D002930:Cinchona Alkaloids; D006571:Heterocyclic Compounds; D007097:Imines; D009570:Nitriles; C542835:ketimine; C007170:cyanoacetic acid