Zhang Chi, Wang Hongye, Zhong Jie, Lei Ye, Du Renfeng, Zhang Yang, Shen Libo, Jiao Tianyu, Zhu Yulu, Zhu Haiming, Li Haoran, Li Hao
Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Sci Adv. 2019 Nov 1;5(11):eaax6707. doi: 10.1126/sciadv.aax6707. eCollection 2019 Nov.
By using click chemistry, a hexacationic cage was synthesized. The cage contains two triscationic π-electron-deficient trispyridiniumtriazine (TPZ) platforms that are bridged in a face-to-face manner by three ethylene-triazole-ethylene linkers. A diversity of π-electron-rich guests can be recognized within the pocket of the cage, driven by host-guest π-π interactions. The cage cavity acts as a protecting group, preventing an anthracene guest from undergoing Diels-Alder reaction. Under ultraviolet (UV) light, the pyridinium C─N bonds in TPZ platforms are polarized and weakened, resulting in the occurrence of cage decomposition via β-elimination. Guest recognition could help to prevent this UV-stimulated cage decomposition by suppressing the excitation of the TPZ units.
通过点击化学合成了一种六阳离子笼。该笼包含两个三阳离子缺π电子的三吡啶基三嗪（TPZ）平台，它们通过三个乙烯 - 三唑 - 乙烯连接基面对面桥连。在主客体π-π相互作用的驱动下，笼的口袋内可以识别多种富π电子的客体。笼腔起到保护基团的作用，防止蒽客体发生狄尔斯 - 阿尔德反应。在紫外（UV）光下，TPZ平台中的吡啶鎓C─N键极化并减弱，导致笼通过β-消除反应分解。客体识别可以通过抑制TPZ单元的激发来帮助防止这种紫外线刺激的笼分解。
