ディオキサゾロンの地域およびエナチオ選択的触媒 δ-C-H アミデーションは,オープンシェル銅-ニトロイド移転によって可能
Suhyeon Kim1,2, Se Lin Song1,2, Jianbo Zhang1,2
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea.
Journal of the American Chemical Society
|July 18, 2023
まとめ
この研究は,銅とキラルリガンドを用いたC-Hアミデーションのための新しい非対称な触媒方法を導入しています. このアプローチは,高度な選択性を持つキラル六つ組のラクトームを効率的に合成し,幅広い合成有用性を示しています.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- C-H機能化における地域選択性およびエナチオ選択性の制御は,複雑な分子の合成に不可欠である.
- C-Hアミデーションは窒素を含む化合物への直接的な経路を提供するが,非対称的な変種は困難である.
研究 の 目的:
- ダイオクサゾロンの δ-C ((sp3) -H アミデーションのための新しい非対称な触媒システムを開発する.
- 六つ組のラクトームの合成において高い地域選択性とエナチオ選択性を達成する.
主な方法:
- キラルビソクサゾリンのリガンドと組み合わせたCu (I) 前駆体を使用した.
- C-H機能化のために非対称な触媒を用いた.
- 実験的および計算的メカニズム研究を実施した.
主要な成果:
- 6基のラクトームの合成において,高いから優れた地域およびエナチオ選択性 (最大>19:1rrおよび>99:1er) が達成される.
- 地域選択的水素原子抽象とCu-nitrenoidsによるエナチオ決定的ラジカルリバウンドを含むメカニズムを明らかにした.
- アザサイクリック化合物へのダイアステレオ選択的機能化とアクセスを通じて,合成的有用性を実証した.
結論:
- 開発された触媒システムは,非対称 δ-C ((sp3) -H アミデーションのための効率的な方法を提供します.
- 機械的洞察は,選択性を制御するオープンシェルのクニートレノイドの役割を強調する.
- このアプローチにより,貴重なキラルラクトームと関連する生物学的化合物への迅速なアクセスが可能になります.
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