Manipulation of molecular geometry using photoresponsive units is a powerful tool in supramolecular chemistry, smart materials, and photopharmacology. Current synthetic chemistry offers many responsive molecules that perform such a task. However, the incorporation of various photoresponsive units in a single molecule to achieve several geometrical changes remains scarce, particularly when they are in close proximity. The development of such systems is limited by challenges arising from selectively addressing the photoresponsive moieties and the analysis of complex mixtures. Here, we overcome these challenges by constructing a novel hetero‐photochromic azobenzene‐oxindole dyad (AOD). Both chromophores can be addressed and quantified in solution by in‐situ NMR irradiation analysis. Additionally, this method allows us to unravel the intricate photokinetic relationships between the two chromophores leading to the observation of an unprecedented molecular motion; an azobenzene E à Z à E isomerization at a single wavelength due to the oxindole influence. By functionalizing the azobenzene ring we showed that the responsiveness of the system is maintained in seven distinct AODs. Overall, the photochromic dyad offers dramatic geometrical changes over its four isomers, making it a useful tool for further applications in which such behavior is desired such as host‐guest systems, responsive materials, photopharmacology and molecular machines.

中文翻译：

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偶氮苯-氧吲哚光致变色二元组


使用光响应单元纵分子几何形状是超分子化学、智能材料和光药理学中的强大工具。当前的合成化学提供了许多执行此类任务的响应性分子。然而，将各种光响应单元掺入单个分子中以实现多种几何变化仍然很少，尤其是当它们非常接近时。这种系统的开发受到选择性处理光响应部分和复杂混合物分析所带来的挑战的限制。在这里，我们通过构建一种新的异质-光致变色偶氮苯-氧吲哚二元组 （AOD） 来克服这些挑战。两种发色团都可以通过原位 NMR 辐照分析在溶液中进行寻址和定量。此外，这种方法使我们能够解开两个发色团之间错综复杂的光动力学关系，从而观察到前所未有的分子运动;由于氧吲哚的影响，偶氮苯 E à Z à E 在单个波长上的异构化。通过对偶氮苯环进行功能化，我们表明系统的响应性在 7 个不同的 AOD 中保持不变。总体而言，光致变色二元组在其四种异构体上提供了巨大的几何变化，使其成为需要这种行为的进一步应用的有用工具，例如主客体系统、响应材料、光药理学和分子机器。