Cp*Rh (III) /Chiral ルイス基協同触媒によるC-H活性化によるエナチオセレクティブサイクル
Takumaru Kurihara1, Masahiro Kojima1, Tatsuhiko Yoshino1,2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Journal of the American Chemical Society
|April 11, 2022
まとめ
新しい協力的触媒システムは,ベンゾラクトームを合成するために,エナチオセレクティブC-H活性化を可能にします. この方法はロジウム複合体とキラルルイス基を使用し,高収量と優れたエナチオ選択性を達成します.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- C-H活性化は有機合成における重要な戦略です.
- C-H機能化のためのエナンチオセレクティブの方法の開発は重要な課題です.
- 協力的触媒は反応性と選択性を高める 有望なアプローチです
研究 の 目的:
- C(sp2) -H活性化によるエナンチオセレクティブの [4+3]サイクル化を開発する.
- Cp*Rh (III) 複合体とキラルルイス基を用いた協力的な触媒システムを確立する.
- 高いエナチオ選択性を持つ様々なベンゾラクトームを合成する.
主な方法:
- Cp*Rh (III) コンプレックスとキラルイソカルコゲン尿素の触媒を含む協同触媒システムを使用する.
- α,β-不飽和アシルアンモニアム中間物質を生成する.
- ロジウム触媒とベンジラミン誘導体から形成された金属サイクルと反応する.
主要な成果:
- C ((sp2) -H活性化によるエナンチオセレクティブ [4+3]サイクリングの成功
- 様々なベンゾラクトームを合成して 生産性が良い.
- エナチオセレクティビティは99:1まで
結論:
- 協同触媒システムは,移行金属触媒化C-H機能化におけるエナチオ選択性を効果的に制御する.
- チラル・ルイス塩基触媒は非対称合成のための強力なツールです.
- この方法論は,エナチオメリックに富んだベンゾラクトームへの効率的なアクセスを提供します.
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