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A highly regio- and stereoselective synthesis of ?-fluorinated imides via fluorination of chiral enamides.

ABSTRACT: A highly ?-facial selective and regioselective fluorination of chiral enamides is described. The reaction involves an enantioselective fluorination exclusively at the electron-rich enamide olefin with N-F reagents such as Selectfluor and N-fluoro-benzenesulfonimide [NFSI] accompanied by trapping of the ?-fluoro-iminium cationic intermediate with water. The resulting N,O-hemiacetal could be oxidized using Dess-Martin periodinane, leading to an asymmetric sequence for syntheses of chiral ?-fluoro-imides and optically enriched ?-fluoro-ketones.

SUBMITTER: Xu YS

PROVIDER: S-EPMC4540344 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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A highly regio- and stereoselective synthesis of α-fluorinated imides via fluorination of chiral enamides.

Xu Yan-Shuang YS Tang Yu Y Feng He-Jing HJ Liu Ji-Tian JT Hsung Richard P RP

Organic letters 20150112 3

A highly π-facial selective and regioselective fluorination of chiral enamides is described. The reaction involves an enantioselective fluorination exclusively at the electron-rich enamide olefin with N-F reagents such as Selectfluor and N-fluoro-benzenesulfonimide [NFSI] accompanied by trapping of the β-fluoro-iminium cationic intermediate with water. The resulting N,O-hemiacetal could be oxidized using Dess-Martin periodinane, leading to an asymmetric sequence for syntheses of chiral α-fluoro- ...[more]

PMID: 25582419

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