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低温でアミドとイミドに塩基触媒による二機能添加. カルボニル水素化の新たな経路
Jeremy M John1, Satoshi Takebayashi, Nupur Dabral
1Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
Journal of the American Chemical Society
|May 22, 2013
まとめ
ノヨリ触媒のデプロトネーションにより,低温でアミドおよびイミドカルボニルを水素化する活性が強化されます. この研究では,触媒の詳細が示されています.
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
- アシンメトリック・シンセシス
背景:
- ノヨリ触媒は,非対称な水素化に不可欠です.
- アミドとイミドの水素化は依然として困難です.
- ルテニウムベースの触媒は,カルボニル還元の可能性を備えています.
研究 の 目的:
- 新しいノヨリ触媒の誘導体を合成し,特徴づけること.
- アミドおよびイミドの水素化におけるこれらの誘導体の触媒的活性を調べる.
- メソサイクルイミドの非対称化におけるエナンチオセレクションのメカニズムを解明する.
主な方法:
- ノヨリケトンの水素化触媒トランス-[RuH2 (((R) -BINAP) (((R,R) -dpen) ] (1a) のモノ・デデプロトネーションとデデプロトネーション
- ポタシウム (8-K) とリチウム (8-Li, 8-M'2) の金属化ルテニウム複合体の合成.
- 低温でTHF-d8でアミドおよびイミドカルボニルの水素化のための活性試験.
- メソサイクリックイミド脱対化のためのエナンチオセレクション起源の詳細な分析.
主要な成果:
- 新しい金属化ルテニウム複合体 (8-K,8-Li,8-M'2) が合成されました.
- これらの複合体は,低温でアミドおよびイミドカルボニル水素化の前例のない活性を示しています.
- 触媒8-Kは,メソサイクルイミドの非対称化において高いエナチオ選択性を示しています.
- THF-d8の低温条件は,この触媒変換に最適です.
結論:
- ノヨリ触媒のデプロトネーションにより,その活性が著しく向上し,その基板の範囲がアミドおよびイミドに拡大する.
- 開発されたルテニウム複合体は,低温水素化反応の非常に効果的な触媒である.
- エナンチオセレクションメカニズムを理解することは,将来の非対称な触媒の設計のための洞察を提供します.
関連する概念動画
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Introduction
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Acid-catalyzed hydrolysis:
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01:29Preparation of Amides
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