パラジウム触媒によるエステルおよびアミドのアルファアリレーションは,より中立な条件下で行われます
Takuo Hama1, Xiaoxiang Liu, Darcy A Culkin
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|October 14, 2005
まとめ
パラジウム触媒による新しい方法は,より穏やかな条件でカルボニル化合物のアルファアリレーションを可能にします. これらの反応は,価値あるエステルおよびアミドを合成するために,高い収量と機能群耐性を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- 伝統的なアルファアリレーションは,しばしば,敏感な機能群と相容れない厳しい条件を必要とします.
- より穏やかで中立的な条件の開発は,より広範な合成アプリケーションにとって不可欠です.
研究 の 目的:
- カーボニル化合物のアルファアリレーションを中性条件下で行う2つの新しい手順について報告する.
- これらの新しい反応において,高収量と機能群耐性を実証する.
主な方法:
- 阻害されたフォスフィンリガンド (Q-phos) と二次性Pd (I) 複合体を持つパラジウム触媒を使用する.
- アルファ-ブロモエステル/アミドから得られた亜鉛エノラートを用い,アリルハリドと反応する.
- 2番目の方法は,亜鉛フッ化物とパラジウム触媒を用いてアリルブロミドと反応するシリルケテン/ケチミンアセタルを用いる.
主要な成果:
- アルファ-アリルエステルおよびアミドの高収量化は,1〜2モル%の触媒負荷で達成される.
- 塩基感受性グループを含む,顕著な機能的グループ耐性を示した.
- ステレオセンターの人種化なしに報告された成功したダイアステレオセレクティブカップリング.
結論:
- 開発された手順は,アルファ-アリレーションのための効率的で穏やかな経路を提供します.
- これらの方法は,パラジウム触媒によるクロスカップリング反応の範囲を拡大します.
- 中立条件は,敏感な機能群とステレオセンターを保ちます.
関連する概念動画
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