Aggregation-Induced-Emission-Active Macrocycle Exhibiting Analogous Triply and Singly Twisted Möbius Topologies

Molecules with Möbius topology have drawn increasing attention from scientists in a variety of fields, such as organic chemistry, inorganic chemistry, and material science. However, synthetic difficulties and the lack of functionality impede their fundamental understanding and practical applications. Here, we report the facile synthesis of an aggregation-induced-emission (AIE)-active macrocycle (TPE-ET) and investigate its analogous triply and singly twisted Möbius topologies. Because of the twisted and flexible nature of the tetraphenylethene units, the macrocycle adjusts its conformations so as to accommodate different guest molecules in its crystals. Moreover, theoretical studies including topological and electronic calculations reveal the energetically favorable interconversion process between triply and singly twisted topologies. Twisted sister: A novel aggregation-induced-emission-active macrocycle, TPE-ET, was synthesized by a simple one-step modified Sonogashira cyclization. TPE-ET adjusts its conformation by virtue of different guest molecules, resulting in intriguing triply and singly twisted Möbius topologies. DFT calculations reveal that the interconversion of these conformations is energetically favorable.