コバルト複合体によって触媒化されたアルケンの非対称性エポキシデーション
Qianwen He1, Mao-Ping Pu1, Zheng Jiang1
1Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
Journal of the American Chemical Society
|July 5, 2023
まとめ
研究者はアルケンのエナチオセレクティブエポキシデーションのための新しいキラルコバルト触媒を開発しました. この突破は"オキソ壁"の課題を克服し,独特のキラルN,N-二酸化物による効率的な非対称合成を可能にします.
科学分野:
- 有機金属化学
- 非対称な触媒
- 有機合成
背景:
- アルケンのエポキシデーションのためのノンヘムキラルマンガンおよび鉄酸素触媒が確立されている.
- クイラルコバルト-酸素触媒は,この変換のために開発されていない.
研究 の 目的:
- 三置換アルケンのエナンチオセレクティブエポキシデーションのための最初のキラルコバルト複合体を報告する.
- コバルト触媒によるエポキシデーションにおけるテトラ酸素ベースのキラルN,N'-二酸化リガンドの役割を調査する.
主な方法:
- PhIOを酸化剤として使用したエナンチオセレクティブエポキシデーション.
- スペクトル検査 (HRMS,UV-vis) と磁気感受性測定
- 密度関数理論 (DFT) の計算と運動研究.
主要な成果:
- キラルコバルト複合体は,循環性および非循環性三置換アルケンのエナチオセレクティブエポキシデーションを成功裏に触媒化した.
- クォーテットCo ((III) - オキシルタウトメールの形成が活性Co-O種として確認された.
- キラルなN,N'-二酸化物リガンドは,中間形成とエナチオセレクティブの酸素転送に不可欠でした.
結論:
- 開発されたキラルコバルト触媒は,オクソ壁の制限を効果的に克服します.
- この研究は,コバルト触媒によるエポキシデーションにおけるエナンチオセレクティビティのメカニズムと起源を解明する.
- この研究は,非対称合成におけるキラルコバルト触媒に新しい道を開きます.
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