N-ヘテロサイクルカルベン-ジルコニウム複合体におけるカーベンとアンモニア活性化への可逆的1,2-アルキル移行
Emmanuelle Despagnet-Ayoub1, Michael K Takase1, Jay A Labinger1
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|August 8, 2015
まとめ
研究者は,制御されたCsp(3) -Csp(3) 結合活性化を可能にするジルコニウム複合体における可逆性ベンジル移行を実証した. アンモニアの添加はベンジル移動とプロトノリシスにつながり,観測可能な中間体を通してブリッジされたダイマーを形成した.
科学分野:
- 有機金属化学
- ジルコニウム触媒
- リガンドの移動
背景:
- ビス ((フェノラート) ベンジリミダゾリデンの複合体は,有機金属化学の鍵である.
- リンガンドダイナミクスを理解することは,触媒応用において極めて重要です.
研究 の 目的:
- ディベンジルジルコニウム複合体とフォスフィンとアンモニアの反応性を調査する.
- リガンドの移動とC-C結合の活性化のメカニズムを探求する.
主な方法:
- ビス ((フェノラート)) ベンジリミダゾリリデン ((ディベンジル)) ジルコニウム複合体のトリメチルフォスフィンとの反応.
- ディベンジル複合体にアンモニアを加える.
- 中間物質を観察するためのNMRスペクトロスコーピー.
主要な成果:
- トリメチルフォスフィン添加は,ジルコニウムからカルベン炭素への可逆的ベンジル移行を誘導した.
- この可逆的な移行により,Csp(3) -Csp(3) 結合が活性化されます.
- アンモニアの添加はベンジル移動とプロトノリシスをもたらし,bis (NH2) -ブリッジドジマーを形成した.
結論:
- オーガノジルコニウム複合体における制御された,可逆性アルキル移動が実証された.
- Csp(3) -Csp(3) の活性化のための新しい経路が特定されました.
- アンモニアとの反応でNMRで観察可能な中間物質を特徴づけた.
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