アリファティックアミンによる好ましい水素アミノアルキル化のためのサイクルウレートタンタール触媒:基板制御反応に対するメカニズム的洞察
Pargol Daneshmand1, Sorin-Claudiu Roşca1, Rosalie Dalhoff1
1Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
Journal of the American Chemical Society
|August 14, 2020
まとめ
新しいタンタール触媒は,活性化されていないアルケンを二次アミンで効率的にアミナ化します. この画期的な発見により 薬剤の改変における応用により 難しい基底でも より迅速で効果的な水素アミノアルキル化が可能になりました
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- 活性化されていないアルケンの触媒アミネーションは,有機合成における重要な課題である.
- ハイドロアミノアルキル化のための効率的な触媒の開発は,価値あるアミンを含む化合物にアクセスするために不可欠です.
研究 の 目的:
- 活性化されていないアルケンを二次アミンで効率的かつ触媒的にアミナ化する新しいタンタール触媒を開発する.
- 新しいシステムによって触媒化された水素アミノアルキル化反応のメカニズムを調査する.
主な方法:
- N,O-ケラートサイクリックウレートタンタル触媒の合成と特徴付け.
- 構造の決定のためのX線結晶学.
- 運動同位体効果 (KIE) とハメット分析を含む運動研究.
主要な成果:
- 最適化されたタンタール触媒は,様々なアリルとアルキルアミンの1オクテンの水素アミノアルキル化に高い活性を示した.
- N-アルキル二次アミン基板に挑戦すると,触媒活性が増加することが観察された.
- ターンオーバー周波数は60h−1に達し,触媒の5mol%の負荷で完全な変換は約20分で達成された.
- 機理学的な研究により,アザメタラサイクル中間物質のプロト解が触媒周回を制限することが明らかになった.
- 電子が豊富なアミン基板は,触媒の周回を促進することが判明した.
結論:
- 非活性化アルケンの二次アミンによる水素アミノアルキル化のための高活性タンタル触媒が開発された.
- 触媒はチャレンジする基板に効果があり,薬物の後期改変の可能性があります.
- 反応メカニズムの理解は,さらなる触媒設計と最適化のための洞察を提供します.
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