メタテシス触媒の解作用:ルテニウム-アミノフォスフィン複合体の実験的および計算的研究
Crystal K Chu1, Tzu-Pin Lin1, Huiling Shao2
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis , California Institute of Technology , Pasadena , California 91125 , United States.
Journal of the American Chemical Society
|April 7, 2018
まとめ
アミノフォスフィンのリガンドを持つルテニウム触媒は,P-N結合により,より速い開始率を示します. リガンド構造は,オレフィン転移とポリメリゼーションにおける触媒活性に大きく影響する.
科学分野:
- 有機金属化学
- カタリシス
- ポリマー科学
背景:
- ルテニウム触媒はオレフィン転移に不可欠である.
- アミノフォスフィンのリガンドは,触媒の活性を調節することができます.
- リンガンド解離を理解することは,触媒の開始の鍵です.
研究 の 目的:
- 第2世代のルテニウムオレフィン転化触媒に対するアミノフォスフィンリガンド構造の影響を調査する.
- フォスフィンの解離と再結合の速度を決定する.
- リンガンドの構造と触媒の開始と活性を相関させる.
主な方法:
- アミノフォスフィンのリガンド構造の系統的な変化
- フォスフィン解離 (k1) と再結合 (k-1) の速度を決定する運動学的研究.
- X線結晶学と密度関数理論 (DFT) の計算.
- リング開きメタテシスポリメリゼーション (ROMP) 実験
主要な成果:
- P-N結合を組み込むことは,親複合体と比較して触媒の開始を加速する.
- Tris (アミノ) フォスフィンのリガンドはより強い結合を示し,開始加速を静止させます.
- リガンド解離は,ステリック,誘導,および構成因子の影響を受けます.
- リガンドの形状の変化は,最も早く発起する触媒の急速な解離に不可欠である.
- ROMPの反応速度は,触媒の開始速度とよく相関する.
結論:
- リガンド構造は,ルテニウム触媒の開始とオレフィン転移の活性に決定的な影響を及ぼします.
- アミノフォスフィンのリガンドは,触媒の設計のために調節可能な性質を提供します.
- 計算と実験データにより,より効率的なルテニウム触媒の開発の洞察が得られます.
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