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Updated: Jun 27, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
08:12

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Published on: August 16, 2018

酸塩化物の触媒的,非対称的なアルファ-フッ化:二重金属-ケテンエノラート活性化による二重金属-ケテンエノラート活性化

Daniel H Paull1, Michael T Scerba, Ethan Alden-Danforth

  • 1Johns Hopkins University, Department of Chemistry, 3400 North Charles Street, Baltimore, Maryland 21218, USA.

Journal of the American Chemical Society
|December 4, 2008
PubMed
まとめ

この研究は,光学的に活性なカルボキシル酸誘導体を生成する,酸塩化物のエナチオセレクティブアルファ-フッ化のための新しい触媒的方法を導入しています. この効率的なプロセスは,二重触媒を使用して,幅広い製品アクセシビリティのための重要な中間物質を生成します.

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Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
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Radical Substitution: Allylic Chlorination

Typically, when alkenes react with halogens at low temperatures, an addition reaction occurs. However, upon increasing the temperature or under reaction conditions that form radicals, providing a low but steady concentration of halogen radicals, allylic substitution reaction is favored. This is because allylic hydrogens are very reactive as the formed intermediate is resonance stabilized. For example, when propene is treated with chlorine in the gas phase at 400 °C, it undergoes allylic...