コバルト触媒による水素原子移転とラジカル・ポラー・クロスオーバーによるアルケンの触媒とシルアンの制御によるエナチオセレクティブ水素機能化
Kousuke Ebisawa1, Kana Izumi1, Yuka Ooka1
1Faculty of Pharmacy, Musashino University, 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
Journal of the American Chemical Society
|July 11, 2020
まとめ
この研究では,コバルト触媒を用いたキラルテトラヒドロフランを合成するための新しい触媒法が導入されました. 反応
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- テトラヒドロフーランは,多くの生物学的活性のある天然製品の重要な構造モチーフです.
- これらの化合物の効率的なエナチオセレクティブ合成は,有機化学における重要な課題である.
研究 の 目的:
- テトラヒドロフランの新種の触媒エナチオ選択合成を開発する.
- トランジション金属触媒化水素原子移転 (TM-HAT) とラジカル・ポラー・クロスオーバー (RPC) を含む反応のメカニズムを解明する.
主な方法:
- 非結合アルケンの水酸化のためにキラルコバルト触媒を使用する.
- 主要な反応剤として*N*-フッ素-2,4,6-コリジニウムテトラフッ素ボラートとディエチルシランを使用しています.
- シランのステリック阻害,添加率,溶媒効果,温度を含む反応パラメータを調査する.
主要な成果:
- テトラヒドロフーランの効率的な合成を達成し,優れたエナチオ選択性 (最大94%) を示した.
- 製品の絶対的な構成は,シランの固体阻害に大きく依存していることが判明した.
- 立体化学的結果に影響を与える2つの競合する選択的メカニズムを特定し,実験データと計算データによって支持された.
結論:
- 開発された方法は,エナチオメリックに濃縮されたテトラヒドロフーランへの多用途な経路を提供します.
- この研究は,シラン構造によって決定される競合する経路を含む,前例のないメカニズム的シナリオを明らかにしています.
- この研究は,移行金属で触媒化された急性反応におけるステレオ化学の制御に関する新しい洞察を提供します.
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