Cp(2) LnH d(0) コンプレックスによるH−H活性化のDFT研究
1Laboratoire de Structure et Dynamique des Systèmes Moléculaires et Solides (UMR5636), Université de Montpellier 2, 34095 Montpellier Cedex 05, France.
Journal of the American Chemical Society
|July 18, 2001
まとめ
ランタニド複合体のH-H結合の活性化エネルギーは低いため,容易な反応が示唆される. ランタン酸エレクトロネガティビティは,このエネルギーに影響を与え,シグマ結合メタテシスが反応機構である.
科学分野:
- 有機金属化学 有機金属化学
- コンピューティング・ケミストリー
- 無機化学 無機化学とは
背景:
- H-H結合の活性化は,多くの触媒プロセスにおける重要なステップです.
- ランタニド複合体は,そのユニークな電子特性と潜在的触媒的用途のためにますます研究されています.
研究 の 目的:
- Cp(2) LnH複合体のH-H結合活性化に必要なエネルギーを計算する.
- 活性化エネルギーに影響を与える要因を調査し,反応機構を明らかにする.
主な方法:
- B3PW91関数を使用した密度関数理論 (DFT) の計算が採用されました.
- H-H結合の解離のための活性化エネルギーは,一連のランタニド複合体のために計算されました.
主要な成果:
- 計算された活性化エネルギーは0.5から8.0kcal/molの範囲で,H-H結合が容易に活性化することを示しています.
- 安定した酸化状態のランタナイドの電子負性は,活性化エネルギー傾向と相関する主要な要因として特定されました.
- 移行状態の幾何学は,短いH-H距離と強い金属-水素相互作用を持つほぼ線形H ((3) ((-)) リガンドを特徴としています.
結論:
- Cp(2) LnH複合体のH−H結合活性化は,エネルギー的にアクセス可能なプロセスです.
- この反応はシグマ結合の転移メカニズムによって進行する.
- ランタナイド金属の電子負性は,H-H結合活性化エネルギーの調節において重要な役割を果たします.
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