エチレン促進対エチレンフリーエニーネメタテシス
Anne G D Grotevendt1, Justin A M Lummiss, Melanie L Mastronardi
1Department of Chemistry; Centre for Catalysis Research & Innovation, University of Ottawa, Ottawa, ON, Canada K1N 6N5.
Journal of the American Chemical Society
|September 17, 2011
まとめ
エチレン添加は,特に阻害が少ない基板では,環閉のエニンメタテシス中に触媒の無効化を防止します. この発見は,ルテニウム触媒反応の最適化に極めて重要です.
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
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- 環を閉じるエニネメタテシスは強力な合成ツールです.
- ルテニウム (Ru) 基のグラブス触媒は,メタテシス反応に広く使用されています.
- 触媒の無効化は,これらの変換の効率を制限することができます.
研究 の 目的:
- エチレンのメタテシス中の触媒の無効化を防止するエチレンの役割を調査する.
- アセチレンエニン存在における触媒の無効化のメカニズムを理解する.
- Grubbsの触媒を用いて触媒の安定性を高めるための戦略を探求する.
主な方法:
- 第1世代と第2世代Grubbsの触媒をリングクロージング・エニーネ・メタテシスに活用した.
- カリブレーションされたガス染色体 - 炎のイオン化検出 (GC-FID) を用いて,触媒の無効化分析を行いました.
- マトリックス・アシスタント・レーザー・デソルプション/イオニゼーション・タイム・オブ・フライト (MALDI-TOF) 質量スペクトロメトリを用いて分析された反応中間物質.
主要な成果:
- 不活性大気下では,プロパルギル質量最小の基板で迅速な触媒の非活性化が観察されました.
- 低反応性で,無効化時に形成されたルテニウム (Ru(エニン) ((2)) 派生体を特定しました.
- エチレンは,不活性なRu(enyne) ((2) 種の形成を抑制し,無効化を防ぐことが実証されました.
結論:
- エチレンは,環閉エニンメタテシス中の触媒活性を維持する上で重要な役割を果たします.
- プロパルギル状態のステリック・バルクは,触媒の非活性化経路を緩和することができます.
- これらの無効化メカニズムを理解することで,触媒の設計を改善し,反応の最適化が可能になります.
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