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Updated: Jul 8, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
06:46

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

ケトンとアルデヒドの直接アルドール反応のための非常に効率的な有機触媒 [修正]

Zhuo Tang1, Zhi-Hua Yang, Xiao-Hua Chen

  • 1Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, 610041, China.

Journal of the American Chemical Society
|June 23, 2005
PubMed
まとめ

チラルL-プロリンアミドは,アルドールの直接反応を効果的に触媒化する. 電子を取り除くグループは,触媒の性能を高め,様々なアルデヒドおよびケトンから高度にエナチオセレクティブのβ-ヒドロキシケトンを生成します.

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Catalysis02:50

Catalysis

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Preparation of Alkynes: Alkylation Reaction

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Introduction
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Aldehydes and Ketones with Alcohols: Hemiacetal Formation

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Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

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In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
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Catalysis

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