銅触媒エナチオコンバージェントラジカルスズキ-ミヤウラ C ((sp3) -C ((sp2) クロスカップリング
Sheng-Peng Jiang1, Xiao-Yang Dong1, Qiang-Shuai Gu2
1Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China.
Journal of the American Chemical Society
|November 4, 2020
まとめ
この研究は,新しい銅触媒のスズキ-ミヤウラ交互結合反応を導入します. 基質制御のためのユニークなリガンドシステムを用いて高いエナチオ選択性を持つキラル分子を効率的に作成します.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- スズキ・ミヤウラ・クロスカップリングは有機合成の重要な反応です
- エナチオセレクティブC ((sp3) -C ((sp2) カップリングを達成することは依然として大きな課題です.
- クロスカップリングにおけるラジカル経路は,しばしばステレオ化学的制御が欠けている.
研究 の 目的:
- C ((sp3) -C ((sp2) 結合形成のためのエナチオセレクティブ銅触媒スズキ-ミヤウラクロスカップリングを開発する.
- ラジカル中間物質を含むクロスカップリング反応におけるステレオ化学を制御する.
- キラル三次ベンジルステレオセンターでエンアンチオ濃縮化合物を合成する.
主な方法:
- キラル・シンコナ・アルカロイド由来 N,N,P-リガンドと組み合わせた 銅触媒を使用した.
- カップリングパートナーとしてラセミックアルキルハリドとオルガンボロナートエステルを使用した.
- ステレオ特異的なSN2プロセスよりも好ましいステレオアブラティブラジカル経路を調査した.
主要な成果:
- スズキ-ミヤウラ交互結合反応で高いエナチオ選択性を達成した.
- 様々なアリル/ヘテロアリルボロナートエステルとアルキルハリドを含む広範な基板範囲が実証されています.
- 開発された方法論では,良い機能的グループ耐性を示した.
結論:
- 開発された方法は,キラル三次ベンジル型ステレオセンターを持つエンアンチオ濃縮化合物への効率的なアクセスを提供します.
- キラルリガンドは,触媒の還元を促進し,中間基を制御する上で重要な役割を果たします.
- この研究は,エナチオセレクティブ・ラジカル・クロスカップリングによる非対称合成を進めている.
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