触媒エナチオセレクティブ水素化のための頑丈なキラルZrベースの金属有機フレームワークのトポロジーベースの機能化
Hong Jiang1, Wenqiang Zhang1, Xing Kang1
1School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Journal of the American Chemical Society
|May 5, 2020
まとめ
安定したキラルジルコニウムベースの金属有機フレームワーク (MOF) を開発し,効率的な非対称な水素化のためのイリジウム触媒をサポートしました. MOFトポロジーは,異質なカタリシスの新しい戦略を提供して,触媒性能を決定します.
科学分野:
- 材料科学
- カタリシス
- 有機化学
背景:
- 繊細な化学薬品と医薬品のグリーン合成には,堅固なサポートされた触媒の開発が不可欠です.
- チラルの金属有機フレームワーク (MOF) は,金属触媒を支えるための調整可能な構造を提供します.
- ジルコニウム (Zr) ベースのMOFは,その安定性と合成の多用途性のために有望である.
研究 の 目的:
- 異なるトポロジーを持つ安定したキラルZrベースのMOFの設計と合成.
- 支持されたイリジウム (Ir) 複合体のネットワーク構造に依存する非対称な触媒性能を調査する.
- 安定したMOFサポーターを使用して異質な非対称な触媒を進める.
主な方法:
- 5つのキラルZr-MOFを構成するために,調節合成とイソレティキュラー拡張戦略が採用されました.
- Zr-MOFは,様々な水溶液における化学的安定性によって特徴づけられた.
- MOFにイリジウム・リン触媒を組み込むために,合成後の改変が使用された.
主要な成果:
- オープンケージを備えた2つのキラルMOFは,最大98%のエナチオメール過剰 (ee) でα-デヒドロアミノ酸エステルの水素化を効率的に触媒化しました.
- 小さいケージを備えた*ith*トポロジーを持つ3つのキラルMOFは,イリジウム触媒を効果的にサポートすることができなかった.
- Zr-MOFにIr-phosphorus触媒を組み込むことで,安定性,耐久性,ステレオ選択性が向上した.
結論:
- チラルZr-MOFは,異質非対称な触媒の非常に安定した支柱として機能する.
- MOFフレームワークのトポロジーは,触媒活動と選択性に大きく影響します.
- この研究は,高度な触媒アプリケーションのためのフレームワークトポロジーに基づく高度なキラルセンターの設計に関する洞察を提供します.
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