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ビスタブル [2] カテナンのスイッチングを制御するには,ドナー-受容体とラジカル-ラジカル相互作用を組み合わせる必要があります

Zhixue Zhu¹, Albert C Fahrenbach, Hao Li

¹Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.

Journal of the American Chemical Society

|July 10, 2012

まとめ

2つの新しいリドックス活性ビスタブル [2] カテナンが合成され,ドナー-受容体またはラジカル-ラジカル相互作用によって誘発される翻訳性同位体間の切り替えのための設計を示しました. これらの機械的に相互接続された分子 (MIMs) は,分子スイッチのための新しい可能性を提供します.

科学分野:

超分子化学超分子化学
マテリアルサイエンス材料科学
有機化学オーガニック・ケミストリー

背景:

機械的に相互接続された分子 (MIM) は,非共性結合によりユニークな性質を備えています.
レドックス活性成分は,分子システムにおける制御可能なスイッチングを可能にします.
応答性分子構造の設計において,ドナー-受容体相互作用は鍵となる.

研究の目的:

新種のリドックス活性ビスタブル [2]カテナンを合成し,特徴づけること.
提供者-受容者,およびラジカル-ラジカル相互作用によって引き起こされるスイッチングメカニズムを調査する.
これらのMIMの潜在能力を分子電子と反応性材料で探求する.

主な方法:

Cu(I) -触媒化されたアジド-アルキンサイクロアディションを用いたドナー-受容体テンプレート誘導合成.
構造的決定のための単結晶X線結晶学.
ダイナミック (1) H NMRスペクトロスコーピー,サイクルボルトメトリー,UV/VISスペクトロエレクトロ化学,および機械学的研究のためのEPRスペクトロスコーピー.

主要な成果:

1,5-ダイオキシナフタレンと4,4'-バイピリジニウム単位を組み込んだ2つのビスタブル [2] カテナンの成功合成.
異なる分子間相互作用によって引き起こされる翻訳性同位体間のリドックス活性スイッチングの実証.
結晶構造は,還元された状態で根幹と根幹の相互作用を確認し,スイッチングメカニズムを検証しました.

結論:

合成された [2] カテナンは,リドックス活性ビスタブルMIMの汎用的な設計戦略を例示しています.
ラジカル-ラジカル認識は,MIMにおける分子スイッチングを制御するための有効なメカニズムです.
これらの発見は,高度な反応性材料と分子デバイスの開発のための基盤を提供します.

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