チラルのα,α-非置換ケトンへの簡潔な経路として,三要素非対称性アリルアルキレーションを特納性触媒で可能にした
Zhenghui Kang1, Wenju Chang2, Xue Tian1
1Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
Journal of the American Chemical Society
|December 6, 2021
まとめ
この研究は,キラルケトンを合成するための新しい3つの成分のアリレーション反応を導入しています. この方法は協力的な触媒システムを用いて複雑な分子を効率的に生成し,非対称合成を進める.
科学分野:
- 有機化学
- キャタリシス
- 非対称合成
背景:
- マルチコンポーネント反応 (MCR) は合成において価値があります.
- アルドル,マンニッヒ,マイケル添加物による一時的なオニウムイリドの検知が確立された.
- オニウムイリドの非対称な触媒的置換型は以前は知られていなかった.
研究 の 目的:
- 新しい3つのコンポーネントのアリレーション反応を開発する.
- オニウムイリドの非対称な触媒置換型の検知を実現する.
- キラル α,α-非置換ケトンを合成する.
主な方法:
- 三次協力型触媒システムを採用している.
- アキラルPd複合体,Rh2~OAc,4とキラルリン酸 (CPA) を利用する.
- 反応するα-ディアゾカルボニル化合物,アルコール,アルリル炭酸.
主要な成果:
- SN1型トラッピングプロセスを通した3つの成分非対称性アリルアルキル化の最初の例.
- Pd-アルリル種とエノール中間物の収束.
- キラルのα,α-非置換ケトンへの迅速なアクセス
- 高いから優れたエナチオ選択性が得られた.
結論:
- 開発された方法は,キラル α,α-非置換ケトンへの効率的な経路を提供します.
- 実験的および計算的研究により,反応メカニズムが解明されました.
- Xantphos リガンドの決定的な役割とエナチオ選択性の起源を特定しました.
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