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Asymmetric addition of α-branched cyclic ketones to allenamides catalyzed by a chiral phosphoric acid.

ABSTRACT: We describe the asymmetric addition of unactivated α-branched cyclic ketones to allenamides catalyzed by a chiral phosphoric acid, generating an all-carbon quaternary stereocenter with broad substrate scope and high enantioselectivity. The products are easily transformed into their corresponding 1,5- and 1,4-ketoaldehyde derivatives, which are both important building blocks in organic synthesis.

SUBMITTER: Yang X

PROVIDER: S-EPMC5155590 | biostudies-literature |

REPOSITORIES: biostudies-literature

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

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