低圧および室温下での動的運動解像度によるアミドの高度なエナントオセレクティブ水素化
Loorthuraja Rasu1, Jeremy M John1, Elanna Stephenson1
1Department of Chemistry, University of Alberta , Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|January 31, 2017
まとめ
新しい触媒システムは,動的運動解像度を使用して,アミドからキラルアルコールを効率的に生成します. この方法は,軽度の条件下で高収量と優れたエナチオ選択性を達成し,非対称な合成を進める.
科学分野:
- 有機化学
- 非対称な触媒
- 緑の化学
背景:
- 非対称な合成のための効率的な触媒システムの開発は,エナチオメリックに純粋な化合物の生産に不可欠です.
- ダイナミック・キネティック・解像度 (DKR) は,ラセミック・スタートマテリアルを単一のエナティオマーに変換するための強力な戦略を提供します.
研究 の 目的:
- 機能化されたアミドの非対称な水素化のための新しい触媒システムの開発と最適化.
- DKRによるキラルアルコールの合成において,高収量とエナチオ選択性を達成する.
主な方法:
- 最適な触媒条件を特定するために,高通量スクリーニングとラボスケールの最適化.
- 特定のルテニウム触媒トランス-RuCl2 (((S,S) -スケフソス) (((R,R) -ドペン) を,イソプロパノール (2-PrOH) に含まれるイソプロポキシド (2-PrONa) と併用した.
- 温和な条件下 (室温,4 atm H2) でα-フェノキシおよび関連アミドの水素化を行った.
主要な成果:
- Trans-RuCl2 (((S,S) -skewphos) (((R,R) -dpen),2-PrONa,および2-PrOHを含む効率的な触媒システムを開発した.
- キラルアルコールの高収量 (最大99%) と優れたエナティオメール過量 (99%e以上) を達成した.
- 室温と低水素圧力 (4 atm) でシステムの有効性を実証した.
結論:
- 開発された触媒システムは,DKRによるアミドの非対称な水素化に非常に有効です.
- この方法は,特殊なステレオ化学的制御を持つ貴重なキラルアルコールへの実用的で効率的な経路を提供します.
- この研究は,持続可能で効率的な非対称合成の方法論の発展に寄与する.
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