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A quadrangular prismatic tricyclooxacalixarene cage 1 based on tetraphenylethylene (TPE) was efficiently synthesized by a one-pot S(N)Ar condensation reaction. As a result of the porous internal structure in the solid state, cage 1 exhibited a good CO2 uptake capacity of 12.5 wt% and a high selectivity for CO2 over N2 adsorption of 80 (273 K, 1 bar) with a BET surface area of 432 m(2) g(-1). Formation of cage 1 led to the fluorescence of TPE being switched on in solution. The system was employed as a single-molecule platform to study the mechanism of aggregation-induced emission (AIE) by examining the restriction of intramolecular rotation (RIR)., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel TPE-based expanded oxacalixarene with typical aggregation-induced emission properties was synthesized by the SNAr reaction of dihydroxytetraphenylethylene with 2,6-dichloropyrazine. The conformation of the oxacalixarene is adjusted by the encapsulated guests (benzene or THF), which results in different supramolecular grid structures in the solid state.

An amphiphilic calix[4]arene bearing branched 3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide groups at the upper rim was synthesized and could increase the solubility of naproxen and ibuprofen in water through hydrogen bonding and π-π stacking interactions. The interactions between amphiphilic calix[4]arene and carboxylic acids such as naproxen and ibuprofen could reverse the direction of the branched substituents and change the shape and size of calixarene micelles from solid to hollow or linear ones.

Chiral calix[4]arenes bearing long tertiary alkyl groups at the upper rim and S-1-phenylethylamine groups at the lower rim can form heat-set gels and egg-like vesicles enantioselectively with d-2,3-dibenzoyltartaric acid in cyclohexane, which is the first example of heat-set gels resulting from difference in interactions between two component gelators: in addition, the diameter of vesicles decreased with the increase in length of alkyl groups, which could be used to control the size of the vesicles.

Chiral para-tert-butylcalix[4]arene bearing (S)-alpha-methylbenzylamine groups at lower rim only self-assembles with one of two enantiomers of 2,3-dibenzoyltartaric acid into coiled nanofibers and the coiled nanofibers only stack with the nanofibers having the same handedness to construct bigger ribbon-like fibers bearing porosity.

Calixarenes bearing optically pure alpha,beta-amino alcohol groups at their lower rim exhibit exceptional and efficient chiral recognition ability in discrimination of racemic mandelic acid, 2,3-dibenzoyltartaric acid and 2-hydroxy-3-methylbutyric acid. [structure: see text]