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Catalytic, Enantioselective 1,2-Difluorination of Cinnamamides.

ABSTRACT: The enantio- and diastereoselective synthesis of 1,2-difluorides via chiral aryl iodide-catalyzed difluorination of cinnamamides is reported. The method uses HF-pyridine as a fluoride source and mCPBA as a stoichiometric oxidant to turn over catalyst, and affords compounds containing vicinal, fluoride-bearing stereocenters. Selectivity for 1,2-difluorination versus a rearrangement pathway resulting in 1,1-difluorination is enforced through anchimeric assistance from a N- tert-butyl amide substituent.

SUBMITTER: Haj MK

PROVIDER: S-EPMC7330813 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Catalytic, Enantioselective 1,2-Difluorination of Cinnamamides.

Haj Moriana K MK Banik Steven M SM Jacobsen Eric N EN

Organic letters 20190409 13

The enantio- and diastereoselective synthesis of 1,2-difluorides via chiral aryl iodide-catalyzed difluorination of cinnamamides is reported. The method uses HF-pyridine as a fluoride source and mCPBA as a stoichiometric oxidant to turn over catalyst, and affords compounds containing vicinal, fluoride-bearing stereocenters. Selectivity for 1,2-difluorination versus a rearrangement pathway resulting in 1,1-difluorination is enforced through anchimeric assistance from a N- tert-butyl amide substit ...[more]

PMID: 30963766

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