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A combination of directing groups and chiral anion phase-transfer catalysis for enantioselective fluorination of alkenes.

ABSTRACT: We report a catalytic enantioselective electrophilic fluorination of alkenes to form tertiary and quaternary C(sp3)-F bonds and generate ?-amino- and ?-aryl-allylic fluorides. The reaction takes advantage of the ability of chiral phosphate anions to serve as solid-liquid phase transfer catalysts and hydrogen bond with directing groups on the substrate. A variety of heterocyclic, carbocyclic, and acyclic alkenes react with good to excellent yields and high enantioselectivities. Further, we demonstrate a one-pot, tandem dihalogenation-cyclization reaction, using the same catalytic system twice in series, with an analogous electrophilic brominating reagent in the second step.

SUBMITTER: Wu J

PROVIDER: S-EPMC3752255 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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A combination of directing groups and chiral anion phase-transfer catalysis for enantioselective fluorination of alkenes.

Wu Jeffrey J Wang Yi-Ming YM Drljevic Amela A Rauniyar Vivek V Phipps Robert J RJ Toste F Dean FD

Proceedings of the National Academy of Sciences of the United States of America 20130806 34

We report a catalytic enantioselective electrophilic fluorination of alkenes to form tertiary and quaternary C(sp3)-F bonds and generate β-amino- and β-aryl-allylic fluorides. The reaction takes advantage of the ability of chiral phosphate anions to serve as solid-liquid phase transfer catalysts and hydrogen bond with directing groups on the substrate. A variety of heterocyclic, carbocyclic, and acyclic alkenes react with good to excellent yields and high enantioselectivities. Further, we demons ...[more]

PMID: 23922394

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