シンプルで高度にZ選択的なルテニウムベースのオレフィンメタテシス触媒
Giovanni Occhipinti1, Fredrik R Hansen, Karl W Törnroos
1Department of Chemistry, University of Bergen, Allégaten 41, N-5007 Bergen, Norway.
Journal of the American Chemical Society
|February 13, 2013
まとめ
トリフェニルベンゼンエチオラートリガンドを搭載した新しいグラブス・ホヴェイダ触媒は,オレフィンメタテシスにおける高いZ選択性を示しています. この強固な触媒は,優れた周回率を達成し,Z選択性を維持し,オレフィン合成のための有望なツールを提供します.
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
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- オレフィンメタテシスは,C=C結合形成のための強力なツールです.
- Grubbs-Hoveydaの第2世代の触媒は広く使用されているが,しばしば高いZ選択性が欠けている.
- 改善されたステレオ選択性を持つ触媒の開発は,標的型合成に不可欠です.
研究 の 目的:
- 新しいグラッブス・ホヴェイダ触媒の変種を合成し,特徴づけること.
- オレフィンメタテシスにおける新しい触媒の触媒活性とZ選択性を評価する.
- 新しい触媒の性能と性質を,その親化合物と比較するために.
主な方法:
- Grubbs-Hoveyda第2世代触媒における塩化物リガンドの1段階置換.
- 2,4,6-トリフェニルベンゼンエチオラートリガンドの合成.
- 末端オレフィンのホモカップリングを含むオレフィン転移反応.
- Zの選択性と売上高の分析.
主要な成果:
- クロリドアニオンを2,4,6-トリフェニルベンゼネチオラートリガンドに置き換えることで,新しい触媒が成功して合成されました.
- 新しい触媒は顕著なZ選択性を示し,末端オレフィンホモカップリングで最大96%を達成した.
- 高い売上高 (2000年までの) と持続的なZ選択性 (>85%) が観察されました.
- 触媒は,親触媒と同じく,酸素と水に対する強度を示した.
結論:
- トリフェニルベンゼネチオラートリガンドを搭載した新しいグラブス・ホヴェイダ触媒は,Z選択オレフィンメタテシスに非常に有効です.
- この触媒は,高い効率と選択性でZ-オレフィンを合成するための貴重な代替手段を提供します.
- その頑丈さと性能特性により,様々な合成用途に適しています.
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