アルケンのヒドロアミン化におけるロジウムフォスフィン-π-アレン中間物質
Zhijian Liu1, Hideaki Yamamichi, Sherzod T Madrahimov
1Department of Chemistry, University of Illinois, Urbana, Illinois 61801-3602, USA.
Journal of the American Chemical Society
|February 12, 2011
まとめ
この研究では,ロジウム触媒による分子内ヒドロアミネーションが,アミンが協調アルケーンに核愛性攻撃することによって発生することを明らかにしています. 反応経路は異常で,可逆性アミン添加に続いて速度を制限するプロトネーションが伴う.
科学分野:
- 有機金属化学 有機金属化学
- 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:
- 内分子ヒドロアミネーションは,有機合成における重要な反応である.
- ロジウム複合体は,様々な有機変異の効果的な触媒である.
研究 の 目的:
- アルケンのロジウム触媒による分子内ヒドロアミナ化とアミンの詳細なメカニズムを解明する.
- 活性な触媒物種と中間物質を特定するために.
主な方法:
- ビアリルダイアルキルホスフィンのリガンドを含むロジウム複合体を用いたメカニズム研究.
- ステレオ化学を決定するために,内部オレフィンにデュテラートアミンを添加する.
- イソトープ効果測定を含む運動学的研究.
主要な成果:
- 活性な触媒は,フォスフィンリガンドを κ(1), η(6) 形式で結合している.
- 反応は,C=C結合にN-H結合のトランス添加を経由して進みます.
- 協調アルケーンに対するアミンの核好性攻撃は逆転可能であり,速度制限プロトネーションが続く.
結論:
- このメカニズムは,調整されたアルケーンに対するアミンの核好性攻撃を含み,典型的なロジウム触媒経路とは異なる.
- 観察されたメカニズムは,パラジアムによって触媒化されたアミドのN-H結合添加と類似性を共有しています.
- この研究は,ロジウム触媒アルケンの機能化に関する新しい洞察を提供します.
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