AUTHOR=Su Hang , Chen Wei , Li Liang , Li Bin , Zhang Zhi-Yuan , Li Chunju 

TITLE=Coordination-Driven Poly[2]Pseudorotaxanes in Highly Polar Organic Solvent

JOURNAL=Frontiers in Chemistry

VOLUME=8

YEAR=2020

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.00579

DOI=10.3389/fchem.2020.00579

ISSN=2296-2646

ABSTRACT=<p>Self-assembly of polypseudorotaxanes in high-polar organic solvents is difficult due to remarkably weak interactions between macrocycles and axles. Reported here is a novel metal-coordinated poly[2]pseudorotaxane constructed by pillar[5]arene, 1,4-bis(4-pyridyl pyridinium)butane, and [PdCl<sub>2</sub>(PhCN)<sub>2</sub>] in highly polar organic solvent of dimethyl sulfoxide (DMSO). Utilizing a combination of <sup>1</sup>H NMR, NOESY, DOSY, DLS, SEM, and viscosity measurements, the formation of polypseudorotaxane was shown to be dependent on the concentration of [2]pseudorotaxanes/[PdCl<sub>2</sub>(PhCN)<sub>2</sub>] and temperature. Furthermore, a temperature-responsive supramolecular gel with reversibly gel–sol transformation was obtained via spontaneous assembly of the polypseudorotaxanes at high concentrations.</p>