水性酸におけるルテニウム触媒C-H水酸化により,アミン誘導体の選択的機能化が可能
James B C Mack1, John D Gipson2, J Du Bois1
1Department of Chemistry, Stanford University , 337 Campus Drive, Stanford, California 94305, United States.
Journal of the American Chemical Society
|June 30, 2017
まとめ
新しい触媒法により,アミンを含有する分子でも,水性酸で選択的なsp3C-H水酸化が可能になる. このルテニウム触媒によるプロセスは,N-酸化よりもC-H酸化を好み,複雑な分子合成のための貴重なツールを提供します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- C−H結合の選択的機能化は有機合成における重要な課題である.
- アミンを含む基質の酸化は,しばしば望ましくないN-酸化副作用を引き起こす.
- 持続可能性のために,水性媒体で動作する触媒システムを開発することが望ましい.
研究 の 目的:
- sp3 C-H 水酸化のための新しい触媒プロトコルを特定し,最適化し,評価する.
- 基本的なアミン機能群で基質を酸化する方法を開発する.
- 水酸化反応の選択性とステレオ化学的結果を調査する.
主な方法:
- 水性酸性条件でバイピリジン (bis) ルテニウム (Ru) 触媒を使用した.
- アミン誘導体とテルペン誘導体の範囲をテストした.
- 触媒の安定性と反応性を評価するために,予備的な運動研究を行った.
主要な成果:
- 選択的三次およびベンジル sp3 C-H 水酸化が達成され,アミン基板のN-酸化を上回る.
- テルペン由来基板では同様の反応傾向が観察された.
- 反応媒体のイオン化強度にもかかわらず,キラル三次中心のエナンチオ固有の水酸化が実証された.
- 予備的な動力学は,シス-およびトランス-ル触媒の構成安定性を示した.
結論:
- 開発されたRu-触媒プロトコルは,水性酸中のアミン含有化合物のsp3C-H水酸化のための選択的方法を提供します.
- この方法は,広範囲の基板と高いステレオ化学制御を示しています.
- 触媒の安定性と選択性は 複雑な分子合成と薬剤発見の可能性を秘めています
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