Redox‐Triggered Chirality Switching and Guest‐Capture/Release with a Pillar[6]arene‐Based Molecular Universal Joint

• Published in: Angewandte Chemie International Edition Vol. 59; no. 21; pp. 8094 - 8098
• Main Authors: Xiao, Chao, Wu, Wanhua, Liang, Wenting, Zhou, Dayang, Kanagaraj, Kuppusamy, Cheng, Guo, Su, Dan, Zhong, Zhihui, Chruma, Jason J., Yang, Cheng
• Format: Journal Article
• Language: English
• Published: Germany 18.05.2020
• Subjects: chirality inversion; electrochemistry; molecular universal joint; pillararene; supramolecular chemistry; molecular universal joint; electrochemistry; pillararene; supramolecular chemistry; chirality inversion
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201916285

A chiral electrochemically responsive molecular universal joint (EMUJ) was synthesized by fusing a macrocyclic pillar[6]arene (P[6]) to a ferrocene‐based side ring. A single crystal of an enantiopure EMUJ was successfully obtained, which allowed, for the first time, the definitive correlation between the absolute configuration and the circular dichroism spectrum of a P[6] derivative to be determined. The self‐inclusion and self‐exclusion conformational change of the EMUJ led to a chiroptical inversion of the P[6] moiety, which could be manipulated by both solvents and changes in temperature. The EMUJ also displayed a unique redox‐triggered reversible in/out conformational switching, corresponding to an occupation/voidance switching of the P[6] cavity, respectively. This phenomenon is an unprecedented electrochemical manipulation of the capture and release of guest molecules by supramolecular hosts. The ins and outs of it: Redox reaction of a chiral electrochemically responsive molecular universal joint leads to a self‐inclusion/exclusion conformational switching. This results in an unprecedented electrochemically controlled binding and release of guest molecules.