As the cucurbit[n]uril (CB[n]) homologue with the largest cavity size, cucurbit[10]uril (CB[10]) can encapsulate big guests to form interesting host–guest complexes/assemblies. Herein, we report the preparation and fluorescence properties of CB[10]-based [2]rotaxane (CB[10]·1) formed from cucurbit[10]uril and dumbbell-like guest 1. This [2]rotaxane (CB[10]·1) is assembled by C═O···N+ ion–dipole interactions between oxygen atoms of the carbonyl fringed portals of CB[10] and the positively charged pyridinium units of 1 via the slipping method under heating at 95 °C in DMSO. In contrast, other cucurbit[n]uril (CB[n], n = 6–8) homologues cannot form rotaxanes with 1 due to their smaller cavities. The dumbbell-like guest 1 is a poor emitter in DMSO. Interestingly, the formation of CB[10]·1 renders the restriction of intramolecular rotation of TPE, which features a strong fluorescent intensity, long lifetime, and high quantum yield. Furthermore, CB[10]·1 is shown to aggregate plate-like structures with various sizes in different solvents (DMSO, THF, or CHCl3), resulting in a stepwise aggregation-induced emission enhancement effect. This kind of CB[10]-based [2]rotaxane may be used to fabricate luminescent systems with unique emission properties.

A crystalline nanotubular framework was constructed by cucurbit[8]uril (CB[8]) molecules in the presence of a molecular chaperone. Compared with amorphous CB[8], the framework exhibits highly selective adsorption for CO2 over N2, CH4, and H2.

•A square [5]molecular necklace was formed from CB[8] and carbazole derivative.•The pH-responsive behaviors of square [5]MN are comprehensively investigated.•CB[8] container as molecular linkers for self-assembly system is presented.The formation of square 5-member molecular necklace ([5]MN) is presented by utilizing the host–guest recognition-driven self-assembly between CB[8] and carbazole derivative 1·2Cl−, which bears two 4,4′-bipyridin-1-ium (BP) arms with a orthogonal geometry. The self-assembly and stimuli-responsive behaviors of square [5]MN are comprehensively investigated by NMR (1H, COSY, NOSEY, and DOSY), UV–vis, DLS, and SEM methods.

Hydrophobic monofunctionalized cucurbit[7]uril derivatives (1 and 2) were synthesized by clicking CB[7]-azide with propargylated alkylamines. Compounds 1 and 2 form self-inclusion complexes that are transformed into vesicle-type assemblies by addition of guests (3–5) as confirmed by 1H and DOSY NMR, SEM, TEM, and fluorescence spectroscopy.

Hydrophobic monofunctionalized cucurbit[7]uril derivatives (1 and 2) were synthesized by clicking CB[7]-azide with propargylated alkylamines. Compounds 1 and 2 form self-inclusion complexes that are transformed into vesicle-type assemblies by addition of guests (3–5) as confirmed by 1H and DOSY NMR, SEM, TEM, and fluorescence spectroscopy.

A crystalline nanotubular framework was constructed by cucurbit[8]uril (CB[8]) molecules in the presence of a molecular chaperone. Compared with amorphous CB[8], the framework exhibits highly selective adsorption for CO2 over N2, CH4, and H2.