高スピンの鉄イミド複合体からの触媒C-H結合アミナーション
Evan R King1, Elisabeth T Hennessy, Theodore A Betley
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
Journal of the American Chemical Society
|March 17, 2011
まとめ
巨大な二ピロメタンリガンドを持つ新しい鉄複合体は,C-Hアミネーションとオレフィンアジリジネーションを触媒化する. 高スピンの鉄 (III) イミドラジカルの中間物質が特定され,これらの反応における触媒活性が説明されました.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 合成化学 合成化学とは
背景:
- ディピロメタンリガンドは,移行金属複合体のための多用途の支架です.
- 鉄複合体は,有機変換の触媒としてますます調査されています.
- 反応メカニズム,特に急性中間物質を含む反応メカニズムを理解することは,触媒設計において極めて重要です.
研究 の 目的:
- 新種の鉄複合体をステリカルに要求される二ピロメタンリガンドで合成する.
- これらの複合体のC-Hアミネーションとオレフィンアジリジネーションにおける触媒的活性を調べる.
- 主要な中間物質の特定を含む,触媒のメカニズムを解明する.
主な方法:
- 1,9-非置換-5-メシチルジピロメテンのリガンドの合成. 大量のアリルまたはアルキル基を持つ.
- NMR,X線結晶学,Mössbauer光譜学などの技術を用いた4座標と3座標の鉄複合体の製造と特徴付け.
- C-Hアミネーションとオレフィンアジリジネーションを含む触媒反応は,運動学的研究と同位体効果測定を行う.
主要な成果:
- 3つの新しい二ピロメタンリガンドとその対応する鉄複合体を成功裏に合成した.
- 独特の3座標の高スピン鉄複合体とステリカルに重荷を負ったアリル置換リガンドを分離した.
- 室温でのC-Hアミネーション (12回トルーエンのターンオーバー) とオレフィンアジリジネーション (>85%のスタイレンへの変換) で触媒活性が実証されています.
- 高スピンのFe (III) イミドラジカル中間物質が特定され,光譜データと運動同位体効果 (12.8 (III) 5) と24 (III) 3) によって証明されました.
結論:
- ステリカルに要求される二ピロメタンリガンドは,異常な鉄の調整複合体の形成を可能にします.
- 単離された高スピンFe (III) イミドラジカルは,触媒アミネーションとアジリディネーション経路における重要な中間物質として提案されています.
- これらの鉄イミド複合体のユニークな電子構造は,観察された触媒反応性に貢献しています.
さらに関連する動画
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If the pH is low or the solution is too acidic, the reaction slows down in the...
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If the pH is low or the solution is too acidic, the reaction slows down in the...
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Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
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