Cu (II) 触媒によるインドルの直接的および部位選択的アリレーションは,温和な条件下で行われます
Robert J Phipps1, Neil P Grimster, Matthew J Gaunt
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK CB2 1EW.
Journal of the American Chemical Society
|June 12, 2008
まとめ
新しい銅触媒反応により,C2またはC3位置でのインドルの選択的アリレーションが可能になる. このC-H結合機能化の方法は,幅広い範囲を提供し,インドルによって制御されます.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 薬用化学 薬用化学について
背景:
- インドール誘導体は,医薬品や天然製品に多く含まれています.
- インドルのサイト選択的機能化は,合成的な課題であり続けています.
- C-Hアクティベーションは,インドール・スキャフォルドの機能化に直接的な経路を提供します.
研究 の 目的:
- インドルアリレーションのための新しいサイト選択方法を開発する.
- インドルのC2対C3アリレーションの制御を達成するために.
- 銅で触媒化されたC-H機能化のメカニズムを探求する.
主な方法:
- 銅 (((II) 触媒によるC-H結合の機能化.
- C2またはC3の位置におけるインドルのサイト選択的アリレーション.
- 提案されたCu (III) - アリル中間物質を含むメカニズム研究.
主要な成果:
- インドルアリレーションのための新しいCu (II) -触媒化されたプロセスを開発しました.
- N置換に基づくC2またはC3アリレーションの高いサイト選択性を達成しました.
- 広範な基板範囲と機能的グループ耐性を実証した.
- Cu (III) - アリル種とC3からC2への移動を含むメカニズムを提案した.
結論:
- 開発された方法は,C2-およびC3-アリレートインドールを合成するための多用途な経路を提供します.
- インドル窒素のN置換は,アリレーション部位の選択性を制御する鍵です.
- このC-H機能化のアプローチは,さらなる合成処理に適しています.
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