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アシンメトリック・ピアス・ヒドロシルレーション
Lars Süsse1, Julia Hermeke1, Martin Oestreich1
1Institut für Chemie, Technische Universität Berlin , Strasse des 17. Juni 115, 10623 Berlin, Germany.
Journal of the American Chemical Society
|May 24, 2016
まとめ
新型キラルボラン触媒は,アセトフェノン誘導体の高度にエナチオセレクティブな水酸化を可能にします. この突破的な非対称反応は,ルイス塩基を必要とせずに99%のエナティオメール過剰 (ee) を達成する.
科学分野:
- 有機金属化学
- 非対称な触媒
背景:
- 効率的な非対称な触媒方法の開発は,エナチオメリックに純粋な化合物を合成するために不可欠です.
- ボラン触媒,特にB ((C6F5) 3) 基は,カルボニル水酸化反応において有望であることが示されている.
- 高いエナチオ選択性を達成するには,しばしば追加のルイス塩基または複雑な触媒システムが必要です.
研究 の 目的:
- アセトフェノンの誘導体の水酸化のための新しい,高度にエナチオセレクティブな触媒システムを開発する.
- ピアーズのB ((C6F5) 3) 触媒化されたカルボニル水溶解の非対称的な変種を調査する.
- 触媒構造と反応条件が,高エナティオメール過量 (ee) を達成する上で果たす役割を調査する.
主な方法:
- 単一のC6F5群を特徴とする軸性キラル,サイクルボラン触媒の合成.
- トライヒドロシランを用いたアセトフェノン誘導体のエナンチオセレクティブ水酸化におけるキラルボラン触媒の適用
- 反応条件の最適化により,エナンチオセレクティブ性と産出量を最大化します.
主要な成果:
- チラルボラン触媒は,アセトフェノン誘導体の高度にエナチオセレクティブな水酸化を成功裏に促進し,最大99%のEEを達成しました.
- 反応は追加のルイス基を必要とせずに効率的に進行した.
- 3,3'-非置換されたビナフチル骨幹からのステリック・コンゲッションと反応性三水素シランの使用は,成功の重要な要因として特定されました.
結論:
- 非対称なカルボニル水酸化には,軸性キラル,サイクルボラン触媒が有効である.
- この方法は,エナチオメリックに濃縮された製品へのルイス塩基のない経路を提供することで,非対称な触媒の重要な進歩を表しています.
- 触媒の設計と還元剤の選択は,この新しい反応で高いエナチオ選択性を達成するために重要です.
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