Department of Chemistry, University of Miami, 33146, Coral GablesMiami, FL, USA.
Photochem Photobiol Sci. 2020 Jul 1;19(7):976-986. doi: 10.1039/d0pp00115e. Epub 2020 Jun 25.
Excited state chemistry and physics of molecules, in addition to their inherent electronic and steric features, depend on their immediate microenvironments. This study explores the influence of an organic capsule, slightly larger than the reactant molecule itself, on the excited state chemistry of the encapsulated molecule. Results presented here show that the confined molecule, in fact, is not isolated and can be manipulated from outside even without direct physical interaction. Examples where communication between a confined molecule and a free molecule present outside is brought about through electronic and energy transfer processes are presented. Geometric isomerization of octa acid encapsulated stilbenes induced by energy and electron transfer by cationic sensitizers that attach themselves to the anionic capsule is examined. The fact that isomerization occurs when the sensitizer present outside is excited illustrates that the reactant and sensitizer are communicating across the molecular wall of the capsule. Ability to remotely activate a confined molecule opens up new opportunities to bring about reactions of confined radical ions and triplet excited molecules generated via long distance energy and electron transfer processes.
除了固有的电子和空间特征外，分子的激发态化学和物理性质还取决于其所处的微环境。本研究探讨了一个略微大于反应物分子本身的有机胶囊对被包裹分子激发态化学的影响。本文展示的结果表明，被限制的分子实际上并没有被隔离，如果没有直接的物理相互作用，也可以从外部进行操纵。本文还介绍了通过电子和能量转移过程，在受限分子和外部自由分子之间进行通信的例子。通过与阴离子胶囊结合的阳离子敏化剂的能量和电子转移诱导的被包裹的肉桂酸的几何异构化进行了研究。当外部存在的敏化剂被激发时，异构化发生的事实表明，反应物和敏化剂正在通过胶囊的分子壁进行通信。能够远程激活受限分子为通过远距离能量和电子转移过程生成的受限自由基离子和三重态激发分子的反应开辟了新的机会。
