リガンド促進メタCHアミネーションとアルキニレーション
Peng Wang1, Gen-Cheng Li1, Pankaj Jain1
1Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States.
Journal of the American Chemical Society
|October 8, 2016
まとめ
研究者は,アニリンとフェノルのための新しいメタ-C-Hアミネーションとアルキニレーション方法を開発した. これらの変換は,改変されたノルボネン媒介体とユニークなピリジンリガンドを使用し,ヘテロサイクルを含む多様な基質の効率的な機能化を可能にします.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 直接的なC-H機能化は,従来の方法と比較してより効率的な合成経路を提供します.
- メタ選択的なC-H機能化は,有機合成における重要な課題である.
- アニリンとフェノール誘導体は,医薬品と材料科学における重要な構成要素です.
研究 の 目的:
- アニリンとフェノール基板のための新しいメタ-C-Hアミネーションとアルキニレーション反応を開発する.
- C-H機能化に挑戦するための一時的なメディエーター戦略を導入する.
- 多種多様なアロマティックおよびヘテロアロマティック化合物に適用できる多用途な方法の確立.
主な方法:
- 変異したノルボレン (メチルビサイクロ[2.2.1]ヘプト-2-エネ-2-カルボキシラート) を一時的な媒介剤として使用した.
- 特別に設計された3アミノ-2-ヒドロキシピリジン/ピリドン型リガンドを使用した.
- メタ-C-H アミネーションとメタ-C-H アルキニレーションの反応条件を調査した.
主要な成果:
- アニリンとフェノールのメタ-CHアミナ化とメタ-CHアルキニル化が初めて報告されました.
- 様々なアニリンおよびフェノール誘導体を含む広範な基板の適用範囲が実証されています.
- インドル,インドリン,インダゾールなどのヘテロサイクリック基板にメソドロジーを成功裏に適用し,中等から高収量製品を得ました.
結論:
- 開発された方法は,メタ機能化されたアニリンとフェノールに前例のないアクセスを提供します.
- 修正されたノルボレンネ媒介体とピリジンリガンドの組み合わせは,反応の成功の鍵です.
- この研究は,特にメタ選択的変換のC-H機能化のためのツールキットを拡張します.
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