転送水素化触媒を用いたダイオキシゲンの均質な触媒還元
Zachariah M Heiden1, Thomas B Rauchfuss
1School of Chemical Sciences, University of Illinois, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|October 26, 2007
まとめ
Cp * IrH ((rac-TsDPEN) のようなイリジウム触媒は,酸素と反応して水を形成することができ,反応速度は触媒と酸素濃度に依存します. この研究は,酸素を含む反応におけるそれらの可能性を調査しています.
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
- 反応の動力学
背景:
- Cp*IrH ((rac-TsDPEN) は,知られている触媒である.
- 分子酸素を含む反応を理解することは,新しい触媒プロセスの開発に不可欠です.
研究 の 目的:
- O2.とCp*IrH(rac-TsDPEN) の反応運動とメカニズムを調査する.
- O2と水素を含む反応におけるこのイリジウム複合体の触媒的可能性を調査する.
主な方法:
- 速度法則と定数を決定するための運動分析.
- 反応メカニズムを調査するための同位体ラベリング研究 (デュテレーション).
- 熱力学パラメータを計算するための温度依存研究.
- H2とO2とアルコールの酸化を用いた触媒実験.
主要な成果:
- 反応は第三次速度法 (触媒の第二次,O2の第一次) に従う.
- ハイドリドの位置でのデュテレーションは比率に大きな影響を与えるが,アミンのデュテレーションはそうではない.
- 触媒は,H2とO2から水の形成を促進し,アルコール酸化を触媒化する.
- 触媒の無効化は,Cp*リガンドの分解と関連しており,これはアミン-ボランによって軽減することができます.
結論:
- Cp*IrH ((rac-TsDPEN) は,従来の転送水素化とは異なるO2とのユニークな反応性を表しています.
- 触媒は,H2. 2から水の形成などの,O2を含む反応における応用の可能性を示しています.
- アミンボランは,リガンドの分解を防止することによって,触媒を安定させることができます.
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