A Dynamic Tetracationic Macrocycle Exhibiting Photoswitchable Molecular Encapsulation

• DOI: 10.1021/jacs.8b10526
• Publication Date: 2018-11-26T19:15:53Z
• Authors: Huang Wu; Yong Chen; Long Zhang; Ommid Anamimoghadam; Dengke Shen; Zhichang Liu; Kang Cai; Cristian Pezzato; Charlotte L. Stern; Yu Liu; J. Fraser Stoddart
• Keywords: Encapsulation

Designing macrocycles with appropriate molecular recognition features that allow for the integration of suitable external stimuli to control host–guest processes is a challenging endeavor which enables containers solubilize, stabilize, and separate chemical entities in an externally controllable manner. Herein, we introduce photo- thermal-responsive elements into semi-rigid tetracationic cyclophane, OPVEx2Box4+, composed oligo(p-phenylenevinylene) pyridinium units biphenylene-bridged 4,4-bipyridinium extended viologens adopts rectangle-like geometry. It transpires when photoactive unit incorporated macrocyclic scaffold, its reversibility dramatically improved, configurations cyclophane can go back forth between (EE)- (EZ)-isomers upon alternating blue light irradiation heating. When macrocycle found (EE)-configuration, it capable binding various π-electron-rich guests—e.g., anthracene perylene—as well as π-electron-deficient 9,10-anthraquinone 5,12-tetracenequinone—through charge-transfer van der Waals interactions. irradiated light, (EE)-isomer be transformed successfully (EZ)-isomer, resulting switching off affinity guest molecules, are bound once again The use heat interactions involving multi-responsive host guests provides us new opportunity design construct more-advanced switches machines.