A new type of macrocyclic arenes, named pagoda[4]arene (P4) and i-pagoda [4]arene (i-P4), were conveniently synthesized by the TFA-catalyzed one-pot condensation of 2,6-dimethoxylanthracene and paraformaldehyde in dichloromethane at room temperature. P4 and i-P4 showed unique square pagoda structures and fixed conformations in solution and also exhibited strong blue fluorescence. Moreover, P4 and i-P4 with deep and rich-electron cavities could not only encapsulate n-hexane and one or two dichloromethane molecules in the solid state but also showed strong binding abilities toward neutral dinitriles with different chain lengths and various nitrogen-containing heterocyclic salts to form 1:1 stable host−guest complexes in both solution and the solid state. In particular, it was also found that with the increase in the alkyl chain length of the dinitriles, the association constants for their complexes with both P4 and i-P4 were markedly increased from glutaronitrile to octanedinitrile as a result of the deep cavities of the macrocycles and multiple intermolecular interactions. Since P4 and i-P4 had stable planar chirality, their efficient resolutions were further achieved by HPLC with a chiral column. Interestingly, the two enantiomers showed mirror-imaged CD signals and excellent CPL properties, which could allow them to have potential applications in chiral luminescent materials.

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Study of enantioselective recognition in water by synthetic chiral macrocyclic receptors is undoubtedly of theoretical and practical significance, but it is a big challenge to achieve the enantioselective recognition with both high enantioselectivity and high affinity in water probably due to the deficiency of such water‐soluble macrocyclic receptors with stable chiral cavities. Herein, we report a new class of chiral macrocyclic arenes named octopus[3]arenes. The enantiomeric macrocycles are composed of three homochiral ethenoanthracene subunits, and they can be synthesized by two pathways and then easily converted into water‐soluble octopus[3]arenes P‐1 and M‐1. Notably, P‐1 and M‐1 with the rigid hexagonal structures and stable chiral hydrophobic cavities exhibit highly enantioselective recognition towards three pairs of chiral ammonium salts in water with the association constant up to 106 M−1 and the S/R selectivity up to 12.89.

In this review, we summarize the recent advances in newly reported macrocyclic arenes, focusing on their synthetic strategies and applications.

Supramolecular tessellation has gained increasing interest in supramolecular chemistry for its structural aesthetics and potential applications in optics, magnetics and catalysis. In this work, a new kind of supramolecular tessellations (STs) have been fabricated by the exo-wall interactions of pagoda[4]arene (P4). ST with rhombic tiling pattern was first constructed by P4 itself through favorable π···π interactions between anthracene units of adjacent P4. Notably, various highly ordered STs with different tiling patterns have been fabricated based on exo-wall charge transfer interactions between electron-rich P4 and electron-deficient guests including 1,4-dinitrobenzene, terephthalonitrile and tetrafluoroterephthalonitrile. Interestingly, solvent modulation and guest selection played a crucial role in controlling the molecular arrangements in the co-crystal superstructures. This work not only proves that P4 is an excellent macrocyclic building block for the fabrication of various STs, but also provides a new perspective and opportunity for the design and construction of supramolecular two-dimensional organic materials.

A pair of inherently chiral belt-shaped conjugated macrocycles were conveniently synthesized starting from 2,7-fluoren[3]arene triflate, and they not only exhibited green fluorescence, but also showed circularly polarized luminescence with |glum|...

Planar chiral organic fluorescent materials that exhibit high chiral stability, high efficiency and circularly polarized luminescence (CPL) concurrently remain an unresolved issue despite their promising applications in optical encryption and...

Although the chemistry of macrocyclic arenes has seen rapid development in recent years, the synthesis of new macrocyclic arenes from aromatic rings with no directing groups remains a challenge. In this work, a new macrocyclic arene, naphth[4]arene (NA[4]A), composed of four naphthalene rings bridged by methylene groups, was synthesized using macrocycle‐to‐macrocycle conversion. NA[4]A shows 1,3‐alternate and 1,2‐alternate conformations in the solid state, which can be selectively obtained. By supramolecular co‐assembly of NA[4]A and 1,2,4,5‐tetracyanobenzene (TCNB) in different concentrations and temperatures, two conformation‐dependent crystalline luminescent co‐assemblies 1,2‐NTC and 1,3‐NTC can be selectively prepared. Interestingly, the two charge‐transfer crystalline assemblies containing NA[4]A with different conformations show bright yellow and green fluorescence, and also display high photoluminescence quantum yields (PLQYs) of 45 % and 43 %. Furthermore, they exhibit color‐tunable two‐photon excited upconversion emission.