プラチナ触媒による分子内水素酸化:アルケンのPt-N結合への挿入の証拠
Jessica M Hoover1, Antonio Dipasquale, James M Mayer
1Department of Chemistry, University of Washington, Campus Box 351700, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|March 26, 2010
まとめ
ディカチオンプラチナ (II) 複合体はアルケンの水素酸化を触媒化し,効率的にN-アミノラクトームを形成する. この発見は,価値あるヘテロサイクリック化合物の新しい合成経路を提供します.
科学分野:
- 有機金属化学 有機金属化学
- オーガニック・シンセシス オーガニック・シンセシス
- カタリシス カタリシス カタリシス
背景:
- アルケンの分子内水素酸化は,窒素を含むヘテロサイクルを合成するための重要な変換です.
- この反応のための効率的で選択的な触媒システムの開発は,有機化学の重要な目標です.
研究 の 目的:
- アルケンの分子内水溶解化のための触媒としてのディカチオン (bpy) Pt (II) 複合体の可能性を調査する.
- 反応条件を最適化し,触媒機構を解明する.
主な方法:
- プラチナ (((bpy)Cl (((2) を含む,プラチナ (((II)) 触媒のスクリーニングは,シルバートリフルオロメタン硫酸塩酸塩 (AgOTf) で行われます.
- 温度,触媒負荷,溶媒などの反応パラメータの最適化 (DMF-d(7)).
- 触媒介質の特徴付けと,N-H活性化とアルケンの挿入を含むメカニズム研究.
主要な成果:
- Pt(bpy) Cl(2) (10 mol %) とAgOTf (20 mol %) は,代用されたヒドラジドの5つ,6つ構成のN-アミノラクトームへの変換を効果的に触媒化する.
- この反応は,5-エクソサイクライゼーション製品のみを産生し,高い地域選択性を示します.
- 触媒的に有能な静止状態であるPt-amidate複合体とPt-alkyl複合体を特定しました.
結論:
- ディカチオンのPt (II) 複合体は,アルケンの分子内水素酸化のための効率的な触媒である.
- 触媒サイクルには,N-Hの活性化,アルケンのPt-N結合への挿入,そしてPt-アミド酸塩触媒の再生が含まれます.
- この方法論は,N-アミノラクトームへの新しい選択的経路を提供します.
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