Surfactant-induced chirality transfer, amplification and inversion in a cucurbit[8]uril–viologen host–guest supramolecular system

Abstract

Chirality manipulation in supramolecules, especially in the multicomponent supramolecular structures is crucially desired. Herein, we report a feasible approach to achieve the chirality transfer, amplification, and inversion in a ternary...

Reversible Inversion of Circularly Polarized Luminescence in a Coassembly Supramolecular Structure with Achiral Sulforhodamine B Dyes

“…The binding constants k 1 ′ = 1.03 × 10 6 M –1 and k 1 ″ = 1.16 × 10 6 M –1 of L4/SRB (1:2) could be obtained by fitting the 1:2 model in the supramolecular binding calculation Web site, , and the average binding constant of L4 and SDS k 1 was 1.10 × 10 6 M –1 , which is close to the binding constants of other supramolecular systems that involved SRB in the literature . The binding constant of L4 and SDS k 2 was 9.56 × 10 5 M –1 , slightly smaller than k 1 . Therefore, SRB and SDS molecules could effectively coassemble with L4 to form stable supramolecular structures according to their large binding constant values.…”

“…We previously reported that one L4 molecule with two positively charged viologen units could coassemble with SDS molecules to form a chiral supramolecular unit. The supramolecular unit could further assemble into chiral helical fibers and show strong CD signals . Herein, we first studied the CPL activity of L4/SDS coassemblies by measuring the FL emission and CPL spectra of L4 aqueous solution (0.05 mM) titrated by different amounts of SDS aqueous solution (0.1 M).…”

“…Titanium dioxide (TiO 2 ) was purchased from EVONIK (Marl, Germany). The amphiphilic compound L4 was synthesized according to the previous literature . Ultrapure water (conductivity 18.2 mΩ/cm, Labconco Corp., Kansas City, MO) was used in all experiments.…”

“…We recently constructed a circular dichroic (CD) active coassembly system consisting of water-soluble chiral molecule L4 (Figure S-1), sodium dodecyl sulfate (SDS), and cucurbit [8]uril (CB [8]) through electrostatic and host−guest interactions. 36 The built supramolecular structure with three components could show dynamic chirality transfer, amplification, and the consequent inversion via evolutions of the supramolecular packing motifs during self-assembly. However, CPL activities were impeded in this supramolecular system because the strong host−guest interactions caused by CB [8] might constrain photoluminescence.…”

Multiple chirality inversion of pyridine Schiff-base cholesterol-based metal–organic supramolecular polymers

“…Supramolecular chirality inversion has attracted widespread attention due to its potential applications in the field of chiral optical switches, circular polarized light-emitting devices, and asymmetric catalysis. 1,2 Usually, the supramolecular chirality of supramolecular polymer-based aggregates in chemical selfassembly systems is collectively affected by the molecular chirality of the building blocks, their packing modes, [3][4][5][6][7] and the external stimuli such as solvent effect, 8,9 pH, 10 temperature, 11 light, 12 metal ions, 13,14 anions, 15 and so forth. Thus, to achieve supramolecular chirality inversion, except for exchanging the enantiomer of the building blocks in the supramolecular polymerization system, the supramolecular interactions such as hydrogen bonds, p-p stacking, metal-ligand coordination, hydrophobic effect, and host-guest interaction also play important roles in controlling the helical sense of supramolecular polymer-based aggregates.…”