レドックス活性カチオン宿主による有機金属カチオンの吸収,捕獲および放出
Iram F Mansoor1, Kaitlyn G Dutton1, Daniel A Rothschild1
1Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 123 Bevier Road, Piscataway, New Jersey 08854, United States.
Journal of the American Chemical Society
|October 1, 2021
まとめ
研究者らは金属有機ナノケージを開発し ゲストを不利な状態に 閉じ込めました この突破は 微妙な刺激を使って ゲストの解放を正確に制御し ホスト-ゲストの化学反応に 新たな道を開きます
科学分野:
- 超分子化学
- 材料科学
- ナノテクノロジー
背景:
- ホスト・ゲストの化学反応は,通常,ゲストの吸収と放出のために熱力学的に有利な相互作用に依存します.
- ナノケージの設計では インタラクションをオン/オフにすることで ゲストの親和感を制御することが 重要な課題です
研究 の 目的:
- 熱力学的に不利な環境で 客を捕まえる金属有機ナノケージを設計する
- 機動的効果と微妙な刺激を使って ゲストの解放を制御する
主な方法:
- ポルフィリン壁のカチオンナノプリズムの合成 (1aおよび1bホスト).
- ホストをズウィテリオン状態に還元し,金属有機カチオン (Cp*2Co+とCp2Co+) を迅速に吸収する.
- メタステーブルな複合体を形成するために,銀 (I) イオン (Ag+) を使用した宿主の再酸化.
- 結合親和性と安定化メカニズムを分析するための実験的および密度関数理論 (DFT) 研究.
主要な成果:
- 還元宿主1aと1bはCp*2Co+とCp2Co+の有機金属カチオンを素早く吸収する.
- Ag+による再酸化はゲストを捕まえて,メタステーブルなカチオン-イン-カチオン複合体 (Cp*2Co@1aとCp2Co@1b) を形成し,1ヶ月以上持続する.
- PF6-アニオンは,静電相互作用と形状の変化によってCp*2Co@1aを運動的に安定させる.
- フェロセニウム (Fc+) を再酸化に使用すると,Ag+と比較して200倍以上の解離が加速されます.
結論:
- 熱力学的に不利な状態の ゲストを金属有機ナノケージに閉じ込める新しい方法を示した.
- メタステーブルな宿主-ゲスト複合体の安定化における運動効果と特殊なカウンターイオンの役割を強調した.
- 熱力学的に有利なシステムよりも微妙な刺激に反応できるということを示した.
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