フッ化カリウムによる水素結合相移転触媒:β-フッ化アミンのエナチオセレクティブ合成
Gabriele Pupo1, Anna Chiara Vicini1, David M H Ascough1
1Chemistry Research Laboratory, University of Oxford , 12 Mansfield Road , Oxford OX1 3TA , United Kingdom.
Journal of the American Chemical Society
|January 29, 2019
まとめ
カリウムフッ素 (KF) は現在,非対称フッ素化の有効な反応剤である. 新しい水素結合相移転触媒法により,KFを用いた有価なβ-フッ素アミンの高産量合成が可能である.
科学分野:
- 有機化学
- 非対称合成
- 化化学
背景:
- カリウムフッ素 (KF) は安全で安価なフッ素化剤である.
- KFの溶解性および反応性制御が悪いため,非対称合成での使用が制限されます.
- 効率的な非対称C−F結合形成戦略の開発は極めて重要です.
研究 の 目的:
- カリウムフッ素を用いた非対称的なフッ素化のための新しい方法を開発する.
- 有機溶剤におけるKFの溶解性と反応性の課題を克服する.
- 高い産量とエナチオ選択性を有する有価なベータフローアミンを合成する.
主な方法:
- KFによる水素結合相移転触媒を用いた.
- KFを溶解するために,キラルなN-エチルビス尿素触媒を使用した.
- 反応性のためにトリコーディネートウレア-フッ素複合体を形成した.
- フロロ・ディフェニジン合成の反応を50gにスケールした.
主要な成果:
- ベータ・フルオアミンの高収量とエナチオ選択性を達成した.
- キラルビス尿素触媒の相移転触媒の有効性を実証した.
- 大量に富んだフッ素・ディフェニジンを 合成しました
- 触媒の回収率と低負荷 (0.5 mol %) を示した.
結論:
- KFによる水素結合相移転触媒は,非対称的な化のための効果的な戦略である.
- この方法は,温和でスケーラブルな条件下で貴重なベータフローアミンを入手できます.
- 開発された方法論は,エナチオセレクティブのC−F結合形成に実用的で効率的なアプローチを提供します.
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