利用超分子策略构筑具有聚集诱导发光(AIE)功能的二苯乙烯型分子开关

Stilbene-Based Molecular Switches with Aggregation Induced Emission(AIE) Function Constructed by Supramolecular Strategy

二苯乙烯型分子开关是构筑具有刺激响应行为的动力学体系的常用单元,不同于常见的四苯基乙烯类化合物,开发具有聚集诱导发光(AIE)功能二苯乙烯型分子开关是一大挑战.利用柱[5]芳烃的超分子作用构筑了一类新型的具有AIE性质的二苯乙烯型分子开关,该类分子开关具有优良的热稳定性,酸催化下能够实现定量的Z→E转化.光驱动的逆过程在光稳态(PSS)时的Z构型选择性达到87%,柱[5]芳烃的引入没有影响母体的开关性能.在混合溶剂[四氢呋喃(THF)-水]中,由于柱[5]芳烃的超分子自组装作用,形成了稳定的聚集体,从而表现出母体分子不具备的AIE性能,这种超分子策略为构筑AIE型分子开关提供了新的思路.

Stilbene derivatives have been widely used for the construction of molecular switches having stimulus-response properties.Unlike the well-known tetraphenyl ethylene derivatives that have aggregation-induced emission(AIE) properties,it is a challenge to develop a stilbene molecular switch with AIE function.In this paper,a new type of stilbene molecular switch with AIE function was constructed by the supramolecular interaction of pillar[5]arene.This type of molecular switch has excellent thermal stability,and quantitative Z→E conversion can be achieved under acid catalysis.The light-driving reverse process achieved 87% of Z-configuration selectivity in the photostable state(PSS).The introduction of pillar[5]arene did not affect the switching performance of the parent compound.In a mixed solvent [tetrahydrofuran(THF)-H2O],a stable aggregate was formed due to the supramolecular self-assembly of pillar[5]arene,which showed the AIE performance that the parent stilbene derivative did not possess.This supramolecular strategy opens a new window for building AIE-type molecular switches.