アレネ C ((sp2) -H パラジウムによる活性化とアルケニル化
Benedikt S Schreib1, Mina Son2, Françoise A Aouane1
1ETH Zurich, Vladimir-Prelog-Weg 3, HCI, 8093 Zurich, Switzerland.
Journal of the American Chemical Society
|December 16, 2021
まとめ
この研究は,ペンタ-1,2,4-トリエンのC-Hアルケニル化のための新しいパラジウム触媒法を導入した. ピコリナミド誘導基は,この反応を促進し,合成後の容易な除去が可能である.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- アレンの選択的なC ((sp2) -H結合活性化は,その固有の反応性のために困難である.
- 移行金属触媒は,アレンの制御された機能化の可能性を提供します.
研究 の 目的:
- 電子的に偏らないアレンのパラジウム触媒C-Hアルケニル化を開発する.
- アレンの選択的C-H活性化のための指向群の使用を調査する.
- ペンタ-1,2,4-トリエンの微生物を合成する
主な方法:
- ピコリナミド誘導基を用いたパラジウム触媒によるC-Hアルケニル化.
- 実験と計算による調査を含むメカニズム研究.
- ピコリナミドN,O-アセタルの取り外し可能な補助物質としての使用
主要な成果:
- ペンタ-1,2,4-トリエンの高収量 (最大94%) を達成した.
- アレニルパルダサイクルの形成とヘック型反応機構が実証された.
- アレニルカルビノール誘導体のアルケニル化にピコリナミドN,O-アセタルを成功裏に利用した.
- 製品が分解されないように 指示群の除去が容易であることが確認された.
結論:
- アルレンの効率的なPd触媒化C-Hアルケニル化を開発した.
- グループアシスタンスとHECK型カップリングを含むメカニズム的な経路を確立しました.
- 簡単に取り除くピコリナミドN,O-アセタルは,C-H活性化のための貴重な補助物質として導入されました.
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