Pressure-driven,solvation-directed planar chirality switching of cyclophano-pillar[5]arenes (molecular universal joints) |
| |
| Authors: | Jiabin Yao Hiroaki Mizuno Chao Xiao Wanhua Wu Yoshihisa Inoue Cheng Yang Gaku Fukuhara |
| |
| Affiliation: | Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, State Key Laboratory of Biotherapy, Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610064 China.; Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 Japan.; Department of Applied Chemistry, Osaka University, Suita 565-0871 Japan.; JST, PRESTO, 4-1-8 Honcho, Kawaguchi Saitama 332-0012 Japan |
| |
| Abstract: | Planar chiral cyclophanopillar[5]arenes with a fused oligo(oxyethylene) or polymethylene subring (MUJs), existing as an equilibrium mixture of subring-included (in) and -excluded (out) conformers, respond to hydrostatic pressure to exhibit dynamic chiroptical property changes, leading to an unprecedented pressure-driven chirality inversion and the largest ever-reported leap of anisotropy (g) factor for the MUJ with a dodecamethylene subring. The pressure susceptivity of MUJs, assessed by the change in g per unit pressure, is a critical function of the size and nature of the subring incorporated and the solvent employed. Mechanistic elucidations reveal that the in–out equilibrium, as the origin of the MUJ''s chiroptical property changes, is on a delicate balance of the competitive inclusion of subrings versus solvent molecules as well as the solvation of the excluded subring. The present results further encourage our use of pressure as a unique tool for dynamically manipulating various supramolecular devices/machines.Pressure switches the in/out conformation of cyclophano-pillararenes with accompanying inversion of the chiroptical properties. |
| |
| Keywords: | |
|
|
