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Direct asymmetric amination of ?-branched cyclic ketones catalyzed by a chiral phosphoric acid.

ABSTRACT: Here we report the direct asymmetric amination of ?-substituted cyclic ketones catalyzed by a chiral phosphoric acid, yielding products with a N-containing quaternary stereocenter in high yields and excellent enantioselectivities. Kinetic resolution of the starting ketone was also found to occur on some of the substrates under milder conditions, providing enantioenriched ?-branched ketones, another important building block in organic synthesis. The utility of this methodology was demonstrated in the short synthesis of (S)-ketamine, the more active enantiomer of this versatile pharmaceutical.

SUBMITTER: Yang X

PROVIDER: S-EPMC4562282 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Direct asymmetric amination of α-branched cyclic ketones catalyzed by a chiral phosphoric acid.

Yang Xiaoyu X Toste F Dean FD

Journal of the American Chemical Society 20150226 9

Here we report the direct asymmetric amination of α-substituted cyclic ketones catalyzed by a chiral phosphoric acid, yielding products with a N-containing quaternary stereocenter in high yields and excellent enantioselectivities. Kinetic resolution of the starting ketone was also found to occur on some of the substrates under milder conditions, providing enantioenriched α-branched ketones, another important building block in organic synthesis. The utility of this methodology was demonstrated in ...[more]

PMID: 25719604

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