コバルト触媒による1,1-非置換アリルアルケンのエナチオセレクティブ水酸化
Lei Zhang1, Ziqing Zuo, Xiaolong Wan
1State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry , 345 Lingling Road, Shanghai 200032, China.
Journal of the American Chemical Society
|October 18, 2014
まとめ
私たちは,非対称な水酸化のための新しいコバルト触媒を開発し,価値あるボロナートエステルを効率的に生産しました. この方法は,抗炎症薬ナプロクセンの効率的な合成を可能にします.
科学分野:
- 有機金属化学 有機金属化学
- アシンメトリック・カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- イミノピリジン-オクサゾリン (IPO) リガンドは,協調化学における多用途の支架である.
- 非対称な水溶解は,キラル分子を合成するための重要な変換です.
研究 の 目的:
- IPOリガンドで新しいコバルト複合体を合成する.
- 1,1-非置換アリルアルケンの非対称な水酸化のためにこれらの触媒を適用する.
- この方法論を用いてナプロクセンの効率的な合成を開発する.
主な方法:
- 新型イミノピリジン-オクサゾリンのリガンドを含むコバルト複合体の合成.
- コバルト触媒を用いた1,1-非置換アリルアルケンの非対称な水酸化.
- ナプロキセンの合成に,水解化製品の適用.
主要な成果:
- 新型コバルト-IPO触媒は,非対称な水力採掘で高収量と優れたエナチオ選択性 (最大99.5% ee) を達成しました.
- 独占的な地域選択性が観察され,α-アルキル-β-ピナコロラトボランを生成しました.
- ナプロクセンへの効率的な合成経路が実証されました.
結論:
- 開発されたコバルト-IPO触媒は,アリルアルケンの非対称な水酸化に非常に効果的です.
- この触媒システムは,キラルボロナートエステルを合成するための実用的なアプローチを提供します.
- この方法論は,価値ある医薬品化合物であるナプロクセンへの効率的な経路を提供します.
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