パラジウムによって触媒化されたスタイレンの非対称な分子間フッ素配列を誘導する
Eric P A Talbot1, Talita de A Fernandes, Jeffrey M McKenna
1Novartis Institutes for Biomedical Research , Horsham,West Sussex, RH12 5AB, United Kingdom.
Journal of the American Chemical Society
|March 13, 2014
まとめ
研究者らは,パラジウム触媒を用いたキラルモノフッ素化合物の生成のための新しい方法を開発しました. この三要素反応は,価値ある sp3 C-F 結合を合成するための温和で効率的な方法を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- フッ素化化学 フッ素化化学
背景:
- 直接的なC-H化は,有機合成における重要な課題であり続けています.
- 非対称な触媒は,エナティオメリカルに純粋な化合物を生成するために極めて重要です.
- C−F結合形成のための触媒的方法の開発は,非常に求められています.
研究 の 目的:
- 軽度で効率的な触媒的非対称性のあるスタイレンの直接的なフッ素アリレーションを開発する.
- 高い収量とエナチオセレクティブ性を持つキラル単化化合物を合成する.
- パラジアム (IV) - フッ化物の中間体を含む反応機構を解明する.
主な方法:
- パラジウムで触媒化された三要素結合反応.
- フッ素の源として,Selectfluorを使用した.
- カップリングパートナーとしてスタイレンとボロン酸を使用した.
主要な成果:
- キラルモノフッ素化合物の良好な収量を達成しました.
- 製品における高いエナティオメール過剰 (ee) が得られた.
- 触媒的非対称性フルオロアリレーションによってsp3 C-F結合を成功して合成した.
結論:
- スタイレンの新しく軽い触媒的非対称な直接フッ素アリレーションが確立されました.
- 開発された方法は,価値あるキラル単化分子へのアクセスを提供します.
- Pd(IV) -フッ素の中間物質を含む提案されたメカニズムが,観察された変換を説明しています.
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