オキシアルリルカチオン触媒:エナチオセレクティブの電離活性化モード
Chun Liu1, E Zachary Oblak1, Mark N Vander Wal1
1Merck Center for Catalysis, Princeton University , Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|January 23, 2016
まとめ
新しい触媒法により,ラセミック前駆体からキラルカルボニル化合物を非対称に合成することができる. このオキシアリルカチオンの化学アプローチは,α-トシロキシケトンのα-インドロカルボニルへの変換において高いエナチオ選択性を達成する.
科学分野:
- 有機化学
- カタリシス
- 非対称合成
背景:
- オキシアリルカチオン化学は,カルボカチオン反応性を理解するための枠組みを提供します.
- 非対称な触媒は,エナチオメリックに純粋な化合物を合成するために不可欠です.
研究 の 目的:
- 非対称的なLUMO低下触媒のための一般的な活性化モードを開発する.
- レーセミックα-トシロキシケトンの光学的に濃縮されたα-インドロカルボニルへのエナチオセレクティブ変換を達成する.
主な方法:
- オキシアリルカチオン化学の原理を用いた.
- 新しいアミノアルコールの触媒を用いて 電子に富んだインドルヌクレオフィルを用いた.
- 反応メカニズムの解明のために運動研究を行った.
主要な成果:
- ラセミカルα-トシロキシケトンを光学的に濃縮されたα-インドロカルボニルに成功裏に変換した.
- 速度決定段階として,触媒介によるα-トシロキシケトン脱プロトン化が特定された.
- 抗差別性オキシアリルカチオンの形成が示された.
結論:
- オキシアリルカチオン化学に基づく非対称合成のための新しい触媒システムを確立した.
- 開発された方法は,キラル α-インドールカルボニル化合物を生産するための実行可能な経路を提供します.
- 反応メカニズムの理解は,エナチオセレクティブのS ((N)) 1経路の洞察を提供します.
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