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Updated: May 1, 2026

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Published on: April 10, 2015

オレフィンメタテシスに関連するルテニウム複合体におけるカルボキシラート補助C(sp3) -H活性化

Jeffrey S Cannon¹, Lufeng Zou, Peng Liu

¹Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.

Journal of the American Chemical Society

|April 16, 2014

まとめ

ルテニウム (II) ベンジリデン複合体は,協調したメタリオン-デプロトネーション機構によってC-H活性化を受けます. このカルボキシラート補助プロセスは,高度に秩序付けられた移行状態を含み,動的同位体効果によって確認されています.

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
反応メカニズム反応メカニズム

背景:

ルテニウム(II) ベンジリデンの複合体は,オレフィンメタテシスの重要な中間物質である.
C-H活性化メカニズムの理解は,触媒の設計と最適化に不可欠です.

研究の目的:

ルテニウム (((II)) ベンジリデン複合体のC-H活性化の詳細なメカニズムを解明する.
C-H活性化を促進するカルボキシラートリガンドの役割を調査する.

主な方法:

直接的なC-H活性化観察のためのルテニウム二炭酸塩化合物の低温合成.
主要運動イソトープ効果の測定を含む運動学的研究 (k ((H)) / k ((D)).
反応経路と移行状態の幾何学を決定するための計算モデリング.

主要な成果:

リガンド交換とは独立して,C-H活性化ステップの直接観察.
1次流動力学と負の活性化エントロピー (ΔS‡ = -5.2 ± 2.6 eu) は,高度に秩序付けられた移行状態を示しています.
実験データは,カルボキシラート補助を含む6つ構成のリングメカニズムを計算した結果と一致しています.
有意な一次運動同位体効果 (k ((H)) / k ((D)) =8.1 ± 1.7) が測定されました.

結論:

C-Hの活性化は,分子内協調メタリオン-デプロトネーションメカニズムを経由して行われます.
カーボキシラートリガンドは重要な役割を果たし,デプロトネーションを容易にするために擬似アピカル幾何学を採用します.
触媒の性能は,カルボキシラート電子とルテニウムリガンド環境の修正によって調整できます.

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