Supramolecular Helical Nanofibers Formed by Achiral Monomers and Their Reversible Sol–Gel Transition

Abstract

Well-defined supramolecular helical nanofibers have been constructed by a rationally designed achiral monomer in aqueous solution based on the 1:2 host-guest combination between cucurbit[8]uril and a 4,4'-bipyridin-1-ium chloride (BPY ) salt derivative. The formed nanostructures could be adjusted by varying the concentration of monomer from helical nanofibers to a pH-responsive hydrogel.

Dynamic Adaptive Two-Dimensional Supramolecular Assemblies for On-Demand Filtration

“…The compound trans- 1 was synthesized. Starting with a previously reported compound 2 (Wang et al., 2017), two steps of etherification reactions were performed to yield compound 3 and 4 . Then the trifluoroacetic acid (TFA) was used to deprotect the phenylamine groups, and triethylamine was used to neutralize the mixture to expose the amino groups.…”

A Modular and Convergent Synthetic Route to Supramolecular Cyclic Dimers Based on Amidinium‐Carboxylate Interactions

“…[13] On the other hand, the attachment of a TMS-protected ethynyl group to commercial 4-iodobenzoic acid, esterification of the carboxylic acid function, and deprotection of the ethynyl group, in that order and under conditions already used previously in similar reactions, gave rise to fragment 10. [15] Then, methyl 4ethynylbenzoate 10 [15] and compound 7 [16] were subjected to a Sonogashira coupling. In order to maximize the yield of the target monocoupled product 11, an excess of 7 was used in this reaction.…”

Alkaline cations dramatically control molecular hydrogelation by an amino acid-derived anionic amphiphile

“…For example, different molecular gelators that experience transitions from cationic to neutral species upon increasing pH values have been reported. [13][14][15][16] Also, a pH decrease associated with the protonation of anions such as carboxylates can promote hydrogelation. [17][18][19] Commonly, the rationale behind pH-regulated molecular hydrogel formation is that ionic species are water soluble, precluding aggregation, while neutralisation initiates a favourable self-assembly and gelation process.…”