アルケンの選択的エアロビックエポキシデーションを促進するための多変性金属有機フレームワークの二重サイトの調節電荷
Hanlin Liu1,2, Wei Liu1,2, Guangxin Xue1
1CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
Journal of the American Chemical Society
|May 10, 2023
まとめ
この研究では,空気を用いた選択的アルケンのエポキシデーションのための金属有機フレームワーク (CuCo-MOF-74) の単一サイトを導入します. この触媒は,アルケンの機能化における課題を克服し,高いスタイレン酸化物の選択性と安定性を達成する.
科学分野:
- 材料科学
- キャタリシス
- 有機化学
背景:
- アルケンの有酸素性エポキシデーションは,工業用途において極めて重要です.
- 高い選択性を達成し,CC結合分裂のような副作用を回避することは,依然として重要な課題です.
研究 の 目的:
- アルケンの高度選択的有酸素エポキシデーションのための新しい触媒システムを開発する.
- 多変量金属有機フレームワーク (CuCo-MOF-74) 内のCu (I) 単一サイトの性能を製造し,調査する.
主な方法:
- CuCo-MOF-74の溶熱合成で,Cu (II) をCu (I) に部分的に還元する.
- フレームワーク内の単一のCu (I),Cu (II),およびCo (II) サイトの特徴
- 空気を酸化剤として使ってスタイレンエポキシデーションの触媒活性と選択性を試験する.
- 触媒メカニズムを解明するためのコントラスト実験と理論的計算を行う.
主要な成果:
- CuCo- MOF-74は,高いスタイレン変換でスタイレン酸化物 (87. 6%) に対する優れた選択性を示した.
- 触媒はCo-MOF-74と比較して選択性が向上し,良好な触媒の安定性を示した.
- 理論的な計算では,Cu (I) サイトは二重のCo (II) とCu (I) サイトでO2の活性化を促進し,エポキシデーションの選択性を高めることが示された.
- 触媒は他のアルケンのエポキシド化にも優れた選択性を示した.
結論:
- CuCo-MOF-74にCu(I) の単一サイトを組み込むことは,有酸素エポキシデーションの選択性を著しく高めます.
- Cu (I) とCo (II) サイト間のシナージ効果は,酸素を活性化し,望ましい反応を促進する鍵です.
- このアプローチは,他の金属有機フレームワークにおけるアルケンのエポキシデーションのための効率的な触媒を製造するための有望な戦略を提供します.
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