Water‐Soluble Pillar[n]arene Mediated Supramolecular Self‐Assembly: Multi‐Dimensional Morphology Controlled by Host Size

Abstract

We report tunable supramolecular self‐assemblies formed by water‐soluble pillar[n]arenes (WPns, n=5–7) and bipyridinium‐azobenzene guests. Nanoscale or microscale morphology of self‐assemblies in water was controlled by the host size of WPn. Supramolecular self‐assemblies could undergo morphology conversion under irradiation with UV light.

Pseudo[n,m]rotaxanes of Cucurbit[7/8]uril and Viologen‐Naphthalene Derivative: A Precise Definition of Rotaxane

“…240-241 o C. IR (cm -1 ) ν: 3104m, 3025m, 1623s, 1587m, 1508m, 1430m, 1329s, 1265m, 815m, 743w. 1 13 C NMR (100 MHz, DMSO-d 6 ) δ: 148. 9,146.2,139.6,133.5,132.3,130.4,128.9,128.8,128.2,128.1,126.8,124.6,121.7.…”

“…Recently, supramolecular chemists have used CB[n] as a macrocyclic host to synthesize many disperse rotaxanes or infinite polyrotaxanes through their unique host-guest properties. For example, one-dimensional (pseudo)rotaxanes based on CB[n] from 1 : 1 or 1 : 2 stoichiometry, [13] two-dimensional network (pseudo)rotaxanes (e.g., polyrotaxane, [14] molecular necklace [15 ]), and extended three-dimensional (pseudo)rotaxanes, [16] have been constructed to exhibit applications in cell imaging, [17] supramolecular organic framework, [18] white-light emissions, [19] and so on. Specifically, CB[8]-based pseudorotaxanes have exhibited a discrete structure of novel 2 : 2 model system of host-guest inclusions.…”

Applications of Supramolecular Polymers Generated from Pillar[n]arene-Based Molecules

“…Pillararenes and their derivatives, with macrocyclic cavities, exhibit robust recognition capacities based on supramolecular interactions, particularly for ions and biomolecules, making them a focal point in this burgeoning field. Structure modifications can be achieved using various methods, including thermal responsiveness [65][66][67], electrochemical responsiveness [68][69][70], redox reactivity [71], and the incorporation of fluorescent [72][73][74][75][76][77][78][79][80] and other functional units [81][82][83][84][85][86][87][88][89]. The chemical structures of pillar[n]arenes and guest molecules mentioned in this section are listed in Scheme 3.…”

Self-revealing kinetically captured self-assembly of a N,N′-diphenyl-dihydrodibenzo[a,c]phenazine derivative

“…The existing methods for characterizing supramolecular self-assembly mainly include scanning electron microscopy (SEM), [18][19][20][21][22] transmission electron microscopy (TEM), [23][24][25][26] atomic force microscopy (AFM), [27][28][29][30][31] confocal laser scanning microscopy (CLSM), [32][33][34] nuclear magnetic resonance (NMR) spectroscopy, [35][36][37][38][39] dynamic light scattering (DLS), [40][41][42][43] etc. Usually, these characterization methods require harsh and costly conditions for sample pretreatment before instrumental detection and analysis, as well as dehydration during preparation and scanning, which might destroy the supramolecular structure, leading to inaccurate results.…”