移行金属のない触媒二重結合メタテシス
Stephen A Bell1, Tara Y Meyer, Steven J Geib
1Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Journal of the American Chemical Society
|September 5, 2002
まとめ
イミノフォスフォランは,カルボジミドC=N結合のメタテシスを触媒化し,金属触媒によるオレフィンメタテシスを模倣する. 隔離されたダイアザホスフェチジンの中間物質は,反応機構と運動を明らかにします.
科学分野:
- オーガノフォスファルス 化学 化学
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- 金属触媒によるオレフィンメタテシスは,有機合成の礎石である.
- 似たような変換のための非金属触媒の開発は非常に望ましい.
- イミノフォスフォランは,新しい触媒経路の探索のためのユニークなプラットフォームを提供します.
研究 の 目的:
- カルボジミドC=N結合メタテシスにおけるイミノフォスファランの触媒活性を調べる.
- この新しい触媒プロセスのメカニズムを解明する.
- 反応中間物質を特徴づけ,運動パラメータを決定する.
主な方法:
- イミノフォスフォラン (X(3) P=NR) の合成と特徴付け.
- C=N結合メタテシスを研究するために,イミノフォスフォランとカルボジミドの反応.
- ディアザフォスフェチジン中間物質の分離と構造的決定.
- 足し算と消去のステップの運動学的研究.
主要な成果:
- イミノフォスフォランは,カルボジミドのC=N結合メタテシスを効果的に触媒化する.
- ディアザフォスフェチジン中間物質は,成功裏に分離され,特徴づけられました.
- オレフィンメタテシスに類似した詳細な添加/除去メカニズムが提案されました.
- 加算 (k ((add) = 1.7 x 10 ((-3) M s ((-1)) と除去 (k ((elim) = 4.0 x 10 ((-4) s ((-1)) の速度定数は決定されました.
- 1.44 TO/P/hの触媒回転頻度 (TOF) は,運動データと一致していた.
結論:
- イミノフォスフォランは,カルボジミドメタテシスに有効な非金属の代替品を提供します.
- 反応は [2+2] サイクル添加と除去を経て進行し,メタテシスの重要な特徴を保ちます.
- そのメカニズムと動力学を理解することは,触媒の最適化と新しい合成方法の開発を容易にする.
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