マグネシウム触媒による水酸化アミネーションにおける協調したC-NとC-H結合形成
James F Dunne1, D Bruce Fulton, Arkady Ellern
1Department of Chemistry and U.S. Department of Energy Ames Laboratory, Iowa State University, Ames, Iowa 50011, United States.
Journal of the American Chemical Society
|December 2, 2010
まとめ
マグネシウム前触媒は,分子内ヒドロアミネーションとサイクリングを促進します. 反応は2つの基質の移行状態を経由して進行し,速度を制限するサイクル化ステップの前に触媒基質結合が先行する.
科学分野:
- オーガノメタリック化学
- カタリシス カタリシス カタリシス
- 有機合成による有機合成です.
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.
- そのような変化のための効率的な前触媒の開発は極めて重要です.
- 反応メカニズムを理解することは,触媒の最適化に不可欠です.
研究 の 目的:
- 協調的に飽和したマグネシウム複合体の触媒活性を調査する.
- 分子内ヒドロアミネーション/サイクリングのメカニズムを解明する.
- 触媒サイクルにおける速度を制限するステップを特定するために.
主な方法:
- マグネシウム前触媒,To(M) MgMe.の合成と特徴づけ
- 速度の法則と反応の順序を決定するための運動学的研究.
- 触媒の静止状態の分離と研究.
- 実験観察に基づくメカニズム提案.
主要な成果:
- マグネシウム複合体To(M) MgMeは,50 °Cでの分子内ヒドロアミネーション/サイクリングの活性前触媒である.
- この反応はミカエリス-メンテン運動に従っており,可逆的な触媒-基板関連性を示しています.
- 隔離可能な静止状態 (マグネシウムアミドアルケネ) は単分子サイクルではなく,基板添加によって活性化されます.
- ターンオーバーを制限するステップのために,2つの基板,6つのセンターの移行状態が提案されています.
結論:
- 触媒サイクルには,マグネシウム触媒と基板の初期可逆結合が含まれています.
- 売上を制限するステップは,提案された6センターの移行状態内で協調したプロセスです.
- この研究は,マグネシウム触媒による水酸化アミネーション/循環反応のメカニズム的な洞察を提供します.
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