オーガノカタリティック・フッ素回転による三次性フッ素ステレオセンターのエナチオセレクティブ構築
Qiang Wang1, Marvin Lübcke1, Maria Biosca1
1Department of Organic Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
Journal of the American Chemical Society
|November 16, 2020
まとめ
チラルのヨウ素 (III) 触媒は新しい酸化性フッ素循環反応を可能にします. この方法では,制御された三次炭素-フッ素ステレオセンターでフッ素テトラヒドロフーランとピロリジンを作り,高いエナチオ選択性を達成します.
科学分野:
- 有機化学
- キャタリシス
- 化化学
背景:
- 酸化性フルオロサイクリングは,フッ素ヘテロサイクルの合成のための重要な変換です.
- ステレオ化学の制御は,特に三次炭素センターでは,合成化学における重要な課題です.
研究 の 目的:
- 1,1-非置換型ステロンの酸化性フルオロサイクリングのための新しい方法を開発する.
- テトラヒドロフランとピロリジン・スキャフォールド内の三次性炭素-フッ素ステレオセンターの形成において高いエナントオ制御を達成する.
主な方法:
- 酸化性フッ素回路化のために,在位で生成されたキラルヨウ素 (III) 触媒を用いる.
- ステレオ選択性を誘発するために,1-ナフチル乳酸由来ヨウ素 (III) -触媒を使用した.
- 反応機構とステレオ選択性を明らかにするために,密度関数理論 (DFT) の計算を行った.
主要な成果:
- 炭素-フッ素ステレオセンターを含むフッ素テトラヒドロフーランとピロリジンを 合成した.
- 新しく開発されたキラルヨウ素 (III) 触媒を用いて最大96%のエナティオメール過量 (ee) を達成した.
- DFT計算は反応経路とステレオ化学的結果に影響を与える要因の洞察を提供した.
結論:
- 開発された酸化性フルオロサイクリングは,エナチオメリックに富んだフッ素ヘテロサイクルのための効率的な経路を提供します.
- チラルのヨウ素 (III) 触媒システムは,三次炭素-フッ素立体センターを制御する重要な可能性を実証している.
- DFT計算によるメカニズムの理解は,将来の触媒システムの合理的な設計に役立ちます.
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