キラルカチオンによって誘導されるエナンチオセレクティブの遠隔C-H活性化
Georgi R Genov1, James L Douthwaite1, Antti S K Lahdenperä1
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Science (New York, N.Y.)
|March 14, 2020
まとめ
研究者は,アニオンのバイピリジンリガンドとキラルカチオンを含むイリジウム複合体を用いて,エナンチオセレクティブC-Hボリレーションのための新しい方法を開発した. この戦略は,非対称化反応における非対称的誘導を可能にし,キラル触媒への新しいアプローチを提供します.
科学分野:
- 有機金属化学
- 非対称な触媒
- 合成有機化学
背景:
- チラルのカチオンは,確立された有機触媒である.
- キラルカチオンを用いたエナチオセレクティブ移行金属触媒は十分に研究されていない.
- キラルアニオンによる 逆電荷戦略は成功しています
研究 の 目的:
- エナチオセレクティブ・トランジションメタル・カタリシスの新しい戦略を開発する.
- チラルカチオンとペアリングされたアニオンリガンドを利用する.
- C-Hボリレーション反応における非対称的誘導を達成する.
主な方法:
- ビピリジン・リガンドのアニオン型変異
- イリジウム複合体の形成とアニオンリガンド
- イリジウム複合体をキラル・キニン系カチオンと組み合わせる
- デシンメトライゼーションのためのエナンチオセレクティブC-Hボリレーションの適用.
主要な成果:
- アシンメトリック誘導のためのイオンペア化イリジウム複合体の成功応用.
- 炭素とリン酸中心のジミナル・ダイアリルモチーフの非対称化が実証された.
- 遠距離非対称制御でエナンチオセレクティブC-Hボリレーションを達成した.
結論:
- 報告された戦略は,アニオンリガンドとキラルカチオンを用いたエナンチオセレクティブ触媒の新たな経路を提供する.
- このアプローチは,幅広いリガンドに適用可能である.
- 非対称な触媒における電荷逆転の可能性を強調する.
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