触媒非対称タンデム反応のためのキラルリン酸による高安定性Zr(IV) 基の金属有機フレームワーク
Wei Gong1, Xu Chen1, Hong Jiang1
1School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites , Shanghai Jiao Tong University , Shanghai 200240 , China.
Journal of the American Chemical Society
|April 16, 2019
まとめ
チラルのリン酸は,リガンド設計戦略を用いて,安定したジルコニウム金属有機フレームワーク (Zr-MOFs) で成功裏に固定されました. これらの異質な触媒は,様々な非対称反応の酸性および選択性を高め,グリーン化学のための有望な経路を提供します.
科学分野:
- 材料科学
- カタリシス
- 有機化学
背景:
- 異質なブロンステッド酸触媒は化学合成に不可欠ですが,高孔性,結晶性,および安定性を備えるのは困難です.
- 既存の方法は,構造的整合性を保ちながら,触媒サイトを効果的に統合するのに苦労します.
研究 の 目的:
- 頑丈なジルコニウムベースの金属有機フレームワーク (Zr-MOF) の内にあるキラルリン酸触媒を固定するための新しいリガンド設計戦略を開発する.
- 非対称なタンデム反応におけるこれらの異質な触媒の触媒性能を調査する.
主な方法:
- エナチオピュア・スピロビンダンを基にしたキラル多孔性Zr(IV) -MOFの合成.
- MOFの構造,多孔性,および安定性の特徴
- 非対称性アセテライゼーション,フリーデル・クラフトス,およびアイソ・ピクテス・スペングラー反応における触媒活性およびエナチオ選択性の評価.
主要な成果:
- 同じトポロジーを有する2つのキラルZr-MOFが,異なるチャネルサイズで,優れた水,酸,塩基耐性を示す.
- ホモゲネスな同類と比較して,固定されたリン酸のブロンステッド酸度が有意に増加していることが示されています.
- 2つの構成要素と3つの構成要素の非対称なタンデム反応の両方で高反応性およびエナチオ選択性を達成し,同質なシステムと比較して比較可能または優れた結果が得られます.
結論:
- リガンド設計戦略は,Zr-MOFにキラルリン酸を効果的に導入し,金属の調整を防止し,安定性を高める.
- その結果生じる異質な触媒は,高い活性,選択性,安定性,再利用性を示し,環境に優しい微細化学合成に有望である.
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