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Ketones as directing groups in photocatalytic sp3 C-H fluorination.

ABSTRACT: The ubiquitous ketone carbonyl group generally deactivates substrates toward radical-based fluorinations, especially sites closest to it. Herein, ketones are used instead to direct aliphatic fluorination using Selectfluor, catalytic benzil, and visible light. Selective ?- and ?-fluorination are demonstrated on rigid mono-, di-, tri-, and tetracyclic (steroidal) substrates employing both cyclic and exocyclic aliphatic ketones as directing groups.

SUBMITTER: Bume DD

PROVIDER: S-EPMC5637129 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Ketones as directing groups in photocatalytic sp3 C-H fluorination.

Bume Desta Doro DD Pitts Cody Ross CR Ghorbani Fereshte F Harry Stefan Andrew SA Capilato Joseph N JN Siegler Maxime A MA Lectka Thomas T

Chemical science 20170811 10

The ubiquitous ketone carbonyl group generally deactivates substrates toward radical-based fluorinations, especially sites closest to it. Herein, ketones are used instead to direct aliphatic fluorination using Selectfluor, catalytic benzil, and visible light. Selective β- and γ-fluorination are demonstrated on rigid mono-, di-, tri-, and tetracyclic (steroidal) substrates employing both cyclic and exocyclic aliphatic ketones as directing groups. ...[more]

PMID: 29147517

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