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Catalytic Asymmetric Synthesis of Chiral ?-Amino Ketones via Umpolung Reactions of Imines.

ABSTRACT: The first direct catalytic asymmetric synthesis of ?-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 ?-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.

SUBMITTER: Hu L

PROVIDER: S-EPMC5654742 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Catalytic Asymmetric Synthesis of Chiral γ-Amino Ketones via Umpolung Reactions of Imines.

Hu Lin L Wu Yongwei Y Li Zhe Z Deng Li L

Journal of the American Chemical Society 20161130 49

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-formi ...[more]

PMID: 27960300

Similar Datasets

Catalytic asymmetric umpolung reactions of imines.

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