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Updated: Jun 12, 2025

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

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

Published on: June 21, 2017

(Z) - スカンジウム触媒によるアリルC-H活性化による1,1-非置換アルケンの選択的異体化

Shao-Jie Lou^1,2, Pan Wang³, Xin Wen³

¹Advanced Catalysis Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

Journal of the American Chemical Society

|September 20, 2024

まとめ

この研究は,1,1-非置換アルケンの (Z) -三置換アルケンを選択的に合成するための新しい方法を導入しています. この新しいアプローチは,一般的な選択性の課題を克服し,有価な有機化合物への効率的な経路を提供します.

科学分野:

有機化学
カタリシス
合成方法論

背景:

1,1-非置換アルケンは,1,3-水素シフトによって三置換アルケンに変換することができる.
このイソメリゼーションは,しばしば,望ましくないE/Z混合物または熱力学的に好ましい (E) -アルケーンを生成する,挑戦的な地域およびステレオ選択性の問題を引き起こす.

研究の目的:

1,1-非置換アルケンの高 (Z) 選択性イソメリゼーションを三置換 (Z) アルケンに発展させる.
制御されたアルケンの合成のためのアリルC-H結合の地域およびステレオ特異的活性化を達成する.

主な方法:

ハーフ・サンドイッチスカンジウム触媒を用いた
選択性を制御する大容量の添加物として2-テルト・ブチルキノリンを使用しています.
このメカニズムを解明するためにデュテリウムラベル実験と密度関数理論 (DFT) の計算を行った.

主要な成果:

1,1-非置換アルケンの前例のない (Z) 選択的異体化が達成された.
C=C結合の転置を促進し,ステリック阻害による選択性を支配する2テート-ブチルキノリンの重要な役割を示した.
高い地域性およびステレオ選択性を持つ様々なアサイクロンおよびエンドサイクロン (Z) - 三置換アルケンを合成しました.

結論:

挑戦的な (Z) 三置換アルケンを合成するための効率的で選択的なプロトコルを開発した.
この方法は,広範囲の基板と100%の原子効率を示しています.
この反応は,前例のないメカニズムで,地域化学的およびステレオ化学的制御のための触媒添加シネージを伴う.

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