Confinement within molecular cages can dramatically modify the physicochemical properties of the encapsulated guest molecules, but such host-guest complexes have mainly been studied in a static context. Combining confinement effects with fast guest exchange kinetics could pave the way toward stimuli-responsive supramolecular systems—and ultimately materials—whose desired properties could be tailored “on demand” rapidly and reversibly. Here, we demonstrate rapid guest exchange between inclusion complexes of an open-window coordination cage that can simultaneously accommodate two guest molecules. Working with two types of guests, anthracene derivatives and BODIPY dyes, we show that the former can substantially modify the optical properties of the latter upon noncovalent heterodimer formation. We also studied the light-induced covalent dimerization of encapsulated anthracenes and found large effects of confinement on reaction rates. By coupling the photodimerization with the rapid guest exchange, we developed a new way to modulate fluorescence using external irradiation.

限制在分子笼内可以显着改变封装客体分子的物理化学性质，但这种主客体复合物主要在静态环境中进行研究。将限制效应与快速客体交换动力学相结合，可以为刺激响应超分子系统（最终是材料）铺平道路，其所需特性可以快速且可逆地“按需”定制。在这里，我们展示了可以同时容纳两个客体分子的开窗配位笼的包合物之间的快速客体交换。使用两种类型的客体，蒽衍生物和 BODIPY 染料，我们表明前者可以在形成非共价异二聚体时显着改变后者的光学性质。我们还研究了封装蒽的光诱导共价二聚化，发现限制对反应速率有很大影响。通过将光二聚化与快速客体交换相结合，我们开发了一种使用外部辐射调节荧光的新方法。