ステレオエレメントを用いた分子モーターの全光化学回転

Gregory B Boursalian¹, Eise R Nijboer¹, Ruth Dorel¹

¹Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

Journal of the American Chemical Society

|September 9, 2020

まとめ

新しい分子モーターは完全に光化学的な片方向の回転を実現しますこれは珍しいことですその独特のの中心は,完全な360°分子モーターの回転サイクルを初めて結晶学的に特徴付けることを可能にします.

科学分野:

有機化学
超分子化学
写真化学

背景:

単方向の分子の回転は通常,光化学と熱学的ステップを組み合わせている.
純粋に光化学的な回転サイクルは分子モーターでは珍しくありません.
過剰に混雑したアルケンは,分子モーターの設計における一般的なモチーフである.

研究の目的:

完全に光化学的な単方向の回転を可能にする新しい第2世代の分子モーターを開発する.
分子運動に対するステレオセンターの影響を調査する
分子モーターの完全な回転サイクルを結晶学的に特徴づけること.

主な方法:

3つの新世代の分子モーターを合成した.
ロータリー動作を分析するための光化学的異体化研究.
そのメカニズムを解明するために運動分析と計算モデリングを行います
すべてのダイアステレオメア状態の構造を決定するX線結晶学.

主要な成果:

新しい分子モーターは完全に光化学的な片方向の回転を示しています
4つのダイアステロエーマー状態は全て光化学的手段によって相互変換される.
混雑したアルケーンベースのモーターの完全な360°回転のためのすべてのダイアステレオメア状態の最初のX線結晶構造が得られた.
ステレオセンターの熱反転は,回転サイクルにショートカットを提供します.

結論:

開発された分子モーターは,純粋に光化学的な回転サイクルを達成する上で重要な進歩を表しています.
ステレオセンターは独特の軸性キラリティを導入し,新しいメカニズム的経路を可能にします.
結晶学的な洞察は分子モーターの動作を原子レベルで前例のない理解を提供します
熱エピメリゼーションは分子運動機能を制御する新しい戦略を提供します

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