エナチオセレクティブ・ラジカルカップリングによるオレフィンの触媒的非対称的還元性アザリレーション
Yajuan Li1, Cuijie Han1, Yanyan Wang2
1International S&T Cooperation Base of Chiral Chemistry, Henan University, Kaifeng 475004, Henan, P. R. China.
Journal of the American Chemical Society
|April 26, 2022
まとめ
この研究は,最初のエナチオセレクティブ光触媒的還元性アザアリレーションを導入し,価値あるキラルイミンを含むアザアレン誘導体を生み出します. この新しい方法は,高収量とエナチオ選択性を得るために二重キラル触媒を使用しています.
科学分野:
- 有機化学
- 光触媒
- 非対称合成
背景:
- 可視光光触媒は,イミンを含むアザレン誘導体を合成するための還元性アザリレーションを可能にします.
- 既存の方法は,地域選択性や軽度な条件などの利点がありますが,過激なカップリングの課題のために,エナチオ選択性が欠けています.
研究 の 目的:
- 最初のエナチオセレクティブ光触媒的還元性アザリレーション法を開発する.
- 根本結合のステップでステレオ化学を制御する 課題を克服するために
主な方法:
- キラル水素結合と光敏感剤の触媒を組み合わせた二重触媒システムを使用します.
- 簡単に入手できる"シンコナ"アルカロイド由来バイ機能触媒を用いる.
主要な成果:
- 最初のエナチオセレクティブ光触媒的還元性アザリレーションを達成した.
- 多種多様なアサイクロンおよびサイクロンエノンを用いて,幅広いエナチオ濃縮アザレンの多様性を合成しました.
- 高い収穫量とエナティオメール過量 (ee) が得られた.
結論:
- チラルの水素結合/光敏感剤触媒は,エナチオ選択的還元性アザリレーションのための有効なプラットフォームを提供します.
- 開発された方法は,価値あるキラルアザレン誘導体にアクセスするための強力な戦略を提供します.
- 高いエナチオ選択性を達成するには,キラル触媒の慎重な選択が不可欠です.
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