title: Catalytic Asymmetric Synthesis of Chiral γ-Amino Ketones via Umpolung Reactions of Imines.
abstract: The first direct catalytic asymmetric synthesis of γ-amino ketones was realized by the development of a highly diastereoselective and enantioselective C-C bond-forming umpolung reaction of imines and enones under the catalysis of a new cinchona alkaloid-derived phase-transfer catalyst. In a loading ranging from 0.02 to 2.5 mol %, the catalyst activates a broad range of trifluoromethyl imines and aldimines as nucleophiles to engage in chemo-, regio-, diastereo- and enantioselective C-C bond-forming reactions with acyclic and cyclic enones, thereby converting these readily available prochiral starting materials into highly enantiomerically enriched chiral γ-amino ketones in synthetically useful yields. Enabled by this unprecedented umpolung reaction of imines, conceptually new and concise routes were developed for the asymmetric synthesis of nitrogen-heterocycles such as pyrrolidines and indolizidines.
authors.affiliation: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors.forename: Lin
authors.initials: L
authors.lastname: Hu
authors.affiliation: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors.forename: Yongwei
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors.forename: Li
authors.initials: L
authors.lastname: Deng
mesh_terms: D002384:Catalysis; D007097:Imines / Q000737:chemistry*; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D007097:Imines; D007659:Ketones