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Catalytic asymmetric defluorinative allylation of silyl enol ethers.

ABSTRACT: The stereocontrolled installation of alkyl fragments at the alpha position of ketones is a fundamental yet unresolved transformation in organic chemistry. Herein we report a new catalytic methodology able to construct α-allyl ketones via defluorinative allylation of silyl enol ethers in a regio-, diastereo- and enantioselective manner. The protocol leverages the unique features of the fluorine atom to simultaneously act as a leaving group and to activate the fluorophilic nucleophile via a Si-F interaction. A series of spectroscopic, electroanalytic and kinetic experiments demonstrate the crucial interplay of the Si-F interaction for successful reactivity and selectivity. The generality of the transformation is demonstrated by synthesising a wide set of structurally diverse α-allylated ketones bearing two contiguous stereocenters. Remarkably, the catalytic protocol is amenable for the allylation of biologically significant natural products.

SUBMITTER: Duran J

PROVIDER: S-EPMC10321495 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Catalytic asymmetric defluorinative allylation of silyl enol ethers.

Duran Jordi J Mateos Javier J Moyano Albert A Companyó Xavier X

Chemical science 20230524 26

The stereocontrolled installation of alkyl fragments at the alpha position of ketones is a fundamental yet unresolved transformation in organic chemistry. Herein we report a new catalytic methodology able to construct α-allyl ketones <i>via</i> defluorinative allylation of silyl enol ethers in a regio-, diastereo- and enantioselective manner. The protocol leverages the unique features of the fluorine atom to simultaneously act as a leaving group and to activate the fluorophilic nucleophile <i>vi ...[more]

PMID: 37416711

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