塩基触媒によるハロゲン移転によって可能になったヘテロアレンの核性C-Hエーテル化
Thomas R Puleo1, Danielle R Klaus1, Jeffrey S Bandar1
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States.
Journal of the American Chemical Society
|August 4, 2021
まとめ
この研究では,2-ハロチオフェンを用いたN-ヘテロアレンのC-Hエステル化のための新しい方法が導入されています. このアプローチは,基本条件下でアルコールを様々なN-ヘテロアレンと効率的かつ地域選択的に結合することを可能にします.
科学分野:
- 有機化学
- 合成化学
背景:
- 直接的なC−H機能化は,現代の有機合成における重要な戦略である.
- N-ヘテロアレンのエーテル化は合成化学における重要な課題である.
研究 の 目的:
- N-ヘテロアレンを直接C-Hエステル化するための一般的で効率的なプロトコルを開発する.
- 様々なN-ヘテロアレンを持つアルコールの地域選択的酸化結合を可能にします.
主な方法:
- 2ハロチオフェンからNヘテロアレンへのハロゲン移転の触媒として,三酸化カリウムを使用する.
- N-ヘテロアリルハリド中間物質の形成に続いて,塩基誘導によるアルコールの置換.
- 低コストの2ハロチオフェンを主要反応剤として使用する.
主要な成果:
- N-ヘテロアレンを直接C-Hエステル化するための一般的なプロトコルが確立された.
- アルコールと1,3-アゾール,ピリジン,ディアジン,ポリアジンとの地域選択的酸化結合が達成された.
- 反応は基本的な条件下で効率的に進行します.
結論:
- 開発された方法は,N-ヘテロアレンでC-O結合形成への直接的な経路を提供します.
- 2-ハロチオフェンの使用は,N-ヘテロアレン機能化のための費用対効果の高い多用途なアプローチを提供します.
- このプロトコルは,機能化されたN-ヘテロアレンにアクセスするための合成ツールボックスを拡張します.
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