有機金属イリジウム複合体による分子酸化触媒の過程における前駆体変換
Ulrich Hintermair1, Stafford W Sheehan, Alexander R Parent
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
Journal of the American Chemical Society
|July 5, 2013
まとめ
Cp* (ペンタメチルcyclopentadienyl) は,イリジウム酸化触媒における犠牲の置換リガンドとして作用する. 失われると,水とCH-酸化触媒のための活性青のジ-イリジウム (IV) 種を形成する.
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
- 無機化学 無機化学とは
背景:
- 均質な酸化触媒は,最適な活動と安定性のために,しばしば特定のリガンド設計を必要とします.
- イリジウム複合体は,酸化反応における触媒的多用性で知られている.
研究 の 目的:
- [Cp*Ir ((III)) ((ケラート)) X) ]酸化触媒におけるCp*リガンドの役割を調査する.
- 活性触媒種の構造と反応性を解明する.
主な方法:
- UV-visおよび1H NMRスペクトロスコピーのスペクトロスコピーは,
- マススペクトロメトリー (MALDI-MS)
- エレクトロフォレシス,TEM-EDX,XPS,17O NMR,共振-ラマンスペクトロスコーピー
- 密度関数理論 (DFT) の計算
主要な成果:
- Cp*リガンドは迅速かつ不可逆的に失われ,活性青色の溶液が形成されます.
- 活性種は bis-μ-oxo di-iridium (IV) 複合体として特定されています.
- ディ-イリジウム (IV) 複合体は,誘導期間なしで水とCH酸化を触媒化する.
- DFT計算は,静止状態の電子構造についての洞察を提供します.
結論:
- Cp*は犠牲のプレースホルダーリガンドとして機能し,触媒の活性化を促進します.
- 特定された二イリジウム (IV) 種は,安定した,高度に活性な触媒形態を表しています.
- [ケラート]の前駆物質は,酸化反応の効果的な前触媒である.
さらに関連する動画
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