メカニカル・ポイント・キラル・ロタキサンによる非対称な触媒
Yusuf Cakmak1, Sundus Erbas-Cakmak1, David A Leigh1
1School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
Journal of the American Chemical Society
|February 3, 2016
まとめ
ロタキサンにおける機械的点キラリティは,非対称な触媒を可能にします. このメカノキロゲネシスアプローチは,エナミンとイミニウム活性化経路を通じて,エナチオセレクティブの有機触媒作用を提供します.
科学分野:
- 超分子化学
- 有機化学
- カタリシス
背景:
- メカニカル・ポイント・キラリティは,立体化学における新しい概念です.
- ロタキサンは分子操作のための ユニークな構造的プラットフォームを提供します
- 非対称な触媒は,エナチオメリックに純粋な化合物を合成するために不可欠です.
研究 の 目的:
- 機械的な点キラリティを [2]ロタキサンで非対称な触媒で利用する.
- 機械的にキラルなロタキサンを用いたエナンチオセレクティブ・オルガノカタリススを達成する.
- エナミンとイミニウム活性化の効率を調査する.
主な方法:
- 糸にボリュームのある [2]ロタキサンの合成
- マクロサイクルのシャットリングを防ぐことにより,ロタキサンエナンティオメアの安定化.
- 機械的にキラルロタキサンを有機触媒として使用する.
主要な成果:
- 安定したロタキサンエナティオマーが生成されました.
- ロタキサンはエナチオセレクティブの有機触媒作用を示した.
- エナミンの活性化は71:29のエナティオメール比 (er) まで達成された.
- イミニウム活性化は68:32のエナティオメール比 (er) まで達成された.
結論:
- ロタキサンにおける機械的点キラリティは,非対称な触媒の実行可能な戦略である.
- メカノキロゲネシスは,エナチオ選択的器官触媒化のための強力なツールを提供します.
- 開発されたロタキサンシステムは,将来の触媒用途に希望を示しています.
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