イリジウム触媒によるラセミック二次アリルトリクロアセチミダートのエナンチオセレクティブフローリネーション
Qi Zhang1, David P Stockdale1, Jason C Mixdorf1
1Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States.
Journal of the American Chemical Society
|September 9, 2015
まとめ
この研究は,アリル化合物の非対称的な化のための効率的なイリジウム触媒法を導入する. この新しいアプローチは,高ステレオ選択性を持つ有価な非循環性フッ素を含む分子へのアクセスを提供します.
科学分野:
- 有機化学
- 有機金属化学
- フッ素化学
背景:
- エナチオセレクティブ・フッ素化は,キラルフッ素を含む有機分子を合成するために不可欠である.
- アリル系をエナチオセレクティブにフッ化させる以前の方法は,特にα-線形置換素を持つ二次アリル系電粒子の制限がある.
研究 の 目的:
- ラセミカル,二次アリル電子の非対称的な化のための穏やかで効率的な方法を開発する.
- 高いエナチオ選択性を持つアサイクリックアリル系にフッ素を選択的に組み込むことを可能にします.
主な方法:
- イリジウム (Ir) 触媒反応を用いた.
- 触媒としてキラル-ダイネ-リゲートされたIr複合体を使用した.
- 亜塩基としてラセミック二次アリルトリクロアセチミダート,フッ化物源としてトリエチアミントリヒドロフッ化物 (Et3N·3HF) を使用した.
主要な成果:
- ラセミカル,二次アリル電子のエナチオセレクティブ・フローリネーションを達成した.
- アサイクリックフッ素を含有する化合物が得られた.
- アシンメトリック・インダクションの 優れたレベルを示し,以前の制限を克服した.
結論:
- 開発されたIr触媒による非対称性フルオリネーションは,有価な非循環性フッ素化合物を合成するための温和で効率的な経路である.
- この方法論は,特に二次アリル基板への挑戦のために,エナンチオセレクティブフッ素化の範囲を拡大します.
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