アニリンとフェノールのリガンド促進メタ-CH塩素化
Hang Shi1, Peng Wang1, Shin Suzuki1
1Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
Journal of the American Chemical Society
|November 3, 2016
まとめ
この研究は,ノルボレンネを用いたアニリンとフェノルのメタ-C-H塩化のための新しいパラジウム触媒法を導入する. 反応は様々なヘテロサイクルを許容し,効率的な変換のために新しいピリドンベースのリガンドを使用します.
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,複雑な分子合成に原子経済的なアプローチを提供します.
- メタセレクティブC-H機能化は,特にアニリンやフェノールなどの電子豊富な芳香系には困難である.
- パラジウム触媒は,CHの活性化と機能化のための強力なツールとして登場しました.
研究 の 目的:
- アニリンとフェノルのための新しいパラジウム触媒メタ-C-H塩化反応を開発する.
- 高いメタ選択性を達成するために,適切な媒介体とリガンドを含む主要な反応成分を特定する.
- 開発された塩素化の方法の範囲と合成の有用性を実証する.
主な方法:
- パラジウム触媒反応は,ノルボルネンを媒介物として使用する.
- 反応条件の最適化,触媒,リガンド,溶媒,温度を含む.
- ピリドンベースの新しいリガンドのスクリーニングは,メタ選択性にとって重要です.
- 様々なアニリン,フェノール,ヘテロサイクルの化合物による基板範囲の調査.
- 塩素化製品の特徴と,その後の変換の探求.
主要な成果:
- アニリンとフェノールのパラジウム触媒メタ-C-H塩素化の成功開発.
- ノルボルネンは,メタポジションに塩素を誘導する有効な媒介物として特定された.
- 新しいピリドン基リガンドは,高収量と選択性の達成に不可欠であると特定されました.
- 反応は幅広い基板範囲を示し,多様な機能群と一般的なヘテロサイクル (インドール,チオフェン,インダゾール) を容認した.
- 塩素化された製品は,その後の様々な変形を経て,この方法の合成の多用途性を示した.
結論:
- アニリンとフェノールの新しく効率的なパラジウム触媒メタC-H塩化が確立された.
- 開発された方法は,電子豊富なアロマティックスのメタポジションに塩素原子を導入するための貴重なツールを提供します.
- 媒介体としてのノルボレンとピリドンベースの新しいリガンドの使用は,反応の成功と広範な適用性の鍵です.
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