A Dynamic Hydrogen‐Bonded Azo‐Macrocycle for Precisely Photo‐Controlled Molecular Encapsulation and Release |
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Authors: | Zecong Ye Zhiyao Yang Lei Wang Lixi Chen Yimin Cai Pengchi Deng Wen Feng Xiaopeng Li Lihua Yuan |
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Abstract: | A light‐responsive system constructed from hydrogen‐bonded azo‐macrocycles demonstrates precisely controlled propensity in molecular encapsulation and release process. A significant decrease in the size of the cavity is observed in the course of the E→Z photoisomerization based on the results from DFT calculations and traveling wave ion mobility mass spectrometry. These macrocyclic hosts exhibit a rare 2:1 host–guest stoichiometry and guest‐dependent slow or fast exchange on the NMR timescale. With the slow host–guest exchange and switchable shape change of the cavity, quantitative release and capture of bipyridinium guests is achieved with the maximum release of 68 %. This work underscores the importance of slow host–guest exchange on realizing accurate release of organic cations in a stepwise manner under light irradiation. The light‐responsive system established here could advance further design of novel photoresponsive molecular switches and mechanically interlocked molecules. |
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Keywords: | Photochemie Prä zise Freisetzung Supramolekulare Chemie Wasserstoffverbrü ckter Makrocyclus Wirt-Gast-Systeme |
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