アシンメトリック・トランスファー・ヒドロゲネーション反応のための新しいクラスである"縛られた"ルテニウム (((II)) 触媒
Jérôme Hannedouche1, Guy J Clarkson, Martin Wills
1Asymmetric Catalysis Group, Department of Chemistry, University of Warwick, Coventry, CV4 7AL.
Journal of the American Chemical Society
|January 30, 2004
まとめ
ルテニウムダイマー4は,効率的なケトン還元のために,モノメリック非対称移転水素化触媒2に変換します. この強力な触媒は,キノコ酸/トリエチラミンを使用して,高収量とエナチオ選択性 (98%eeまで) を達成します.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・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:
- ルテニウム複合体は,有機変換における触媒として広く研究されている.
- アシンメトリック・トランスファー・ヒドロゲネーションは,キロアルコールをケトンから合成するための重要な方法である.
- 効率的で頑丈な触媒の開発は,実用的な応用のために不可欠です.
研究 の 目的:
- ルテニウム二重体 (4) が単体触媒 (2) に直接変換される過程を調査する.
- ケトンの非対称的転移水素化における触媒2の有効性を評価する.
- サブストラット特有の用途のための触媒改変の可能性を調査する.
主な方法:
- ルテニウムジマー4を単体触媒に直接変換する 2.
- ケトン還元は,ヒ素源として,甲酸/トリエチラミン中の触媒2を用いてケトン還元.
- 反応変換とエナチオ選択性 (ee) の分析.
主要な成果:
- ルテニウムダイマー4は,反応条件下で直接単体触媒2に変換される.
- Catalyst 2は,高いエナチオ選択性 (98% eeまで) を有する定量ケトン還元を実現します.
- 低触媒負荷 (0.25-0.5 mol %) が有効である.
結論:
- モノメリックルテニウム触媒2は,非対称ケトン還元のための非常に効果的で堅固な単一反応剤触媒です.
- 触媒システムは,広範な適用性とさらなる最適化の可能性を示しています.
- (1R,2S) - ノルエフェドリンから派生した類似した触媒も合成され,研究された.
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