オキシムエステルによる芳香C-H結合のパラジウム触媒アミネーション
1Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|March 2, 2010
まとめ
研究者らは,オキシムエステルを使用して,直接の芳香C-H結合アミネーションのための新しい方法を開発しました. このパラジウム触媒反応は,温和な条件下でインドール産物を形成し,新しい合成経路を提供する.
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
- 合成方法論 合成方法論
背景:
- 直接的なC-H結合の機能化は,合成化学の重要な分野である.
- アロマティックC-Hアミネーションのための効率的で選択的な方法の開発は,依然として課題です.
- パラジウム触媒は,C-H活性化と機能化のための多用途な経路を提供します.
研究 の 目的:
- アロマティックなC−H結合の直接アミネーションのための新しい,概念的に新しいアプローチを導入する.
- 酸化還元中性条件下でのオキシムエステルと芳香C-H結合の反応を調査する.
- パラジウム種を含む触媒機構を調査するために.
主な方法:
- オキシームエステルをアミネート剤として利用する.
- パラジウム触媒を低負荷 (1モル%) で使用する.
- レドックス中性条件下で反応を行う.
- 中間パラジウム複合体を分離し,特徴づけること.
主要な成果:
- アロマティックなC-H結合の直接アミネーションが成功しました.
- インドール産物は,オキシムエステルと芳香C-H結合の反応によって形成された.
- 触媒プロセスは,低パラジウム触媒負荷で動作します.
- Pd(0) 種にN-O結合の異常な初期酸化添加が提案された.
- N-X結合の酸化添加から生じるPd(II) コンプレックスが初めて分離されました.
結論:
- 直接のアロマティックC-Hアミネーションのための新しい効率的な方法が確立されました.
- 反応は,最初のN-O結合の酸化添加をパラジウムに伴う提案されたメカニズムを通じて進行します.
- 重要なパラジウム中間物の分離は,提案された触媒サイクルのための証拠を提供します.
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