Strategies for Constructing Macrocyclic Arene-Based Color-Tunable Supramolecular Luminescent Materials.

Over the past decades, supramolecular luminescent materials (SLMs) have attracted considerable attention due to their dynamic noncovalent interactions, versatile functions, and intriguing applications in many research fields. From construction to application, great efforts and progress have been made in color-tunable SLMs in recent years. In order to realize multicolor luminescence, various design strategies have been proposed.

Advances in circularly polarized luminescence materials based on chiral macrocycles.

Development of circularly polarized luminescence (CPL) materials utilizing supramolecular strategies has recently attracted increasing interest in supramolecular chemistry and materials science. Chiral macrocycles, especially chiral macrocyclic hosts, have stable structures, adjustable internal cavities to encapsulate different guests, and host-guest complexation to induce special photophysical properties. Consequently, various CPL materials based on chiral macrocycles have been developed during the last decade.

Naphth[4]arene: Synthesis, Conformations, and Application in Color-Tunable Supramolecular Crystalline Assemblies.

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.

Complexation with pagoda[]arene ( = 4, 5) protects ferrocenium from oxidation.

The complexation behaviors of pagoda[]arenes ( = 4, 5) with ferrocene, ferrocenium and analogues cobaltocenium were studied. The inclusion complexes of pagoda[]arenes can protect ferrocenium from oxidation in organic solvents and improve the stability and oxygen resistance of ferrocenium.

Recent advances in the synthesis and applications of macrocyclic arenes.

Macrocyclic arenes including calixarenes, resorcinarenes, cyclotriveratrylene, pillararenes and so on have emerged as highly attractive synthetic macrocyclic hosts due to their unique structures, facile functionalization, and broad range of applications. In recent years, there has been growing interest in the development of novel macrocyclic arenes composed of various aromatic building blocks bridged by methylene groups, which have found applications in various research areas. Consequently, the development of novel macrocyclic arenes has become a frontier and hot topic in supramolecular and macrocyclic chemistry.

Pagoda[]arenes ( = 4, 5): Extremely Strong Binders for the Tropylium Cation.

Herein, host-guest complexation between pagoda[]arenes ( = 4, ; = 5, ) and tropylium cation () was investigated in detail. It was found that both and showed surprisingly strong binding affinities toward the tropylium cation with association constants of more than 10 M for the 1:1 host-guest complexes. The theoretical calculations showed different host-guest complexion ways for complexes @ and @ and the strong π···π interactions and multiple C-H···π interactions play a very important role in the formation of these stable complexes, respectively.

Inherently chiral belt-shaped conjugated macrocycles with strong fluorescence and circularly polarized luminescence.

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 a || of 2.0 × 10.

A novel thermally activated delayed fluorescence macrocycle.

A novel luminescent macrocycle has been conveniently synthesized, which displays flexible conformations and interesting solid-state host-guest properties. Besides, the macrocycle exhibits excellent thermally activated delayed fluorescence (TADF) emission with a photoluminescence quantum yield of 80%, which represents the highest value among reported TADF macrocycles.

Enantiomeric Water-Soluble Octopus[3]arenes for Highly Enantioselective Recognition of Chiral Ammonium Salts in Water.

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.

Supramolecular tessellations by the exo-wall interactions of pagoda[4]arene.

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.

D-π*-A type planar chiral TADF materials for efficient circularly polarized electroluminescence.

Planar chiral organic fluorescent materials that exhibit high chiral stability, high efficiency and circularly polarized luminescence (CPL) currently remain an unresolved issue despite their promising applications in optical encryption and 3D-display. Herein, a pair of new donor-chiral π-acceptor (D-π*-A) type planar chiral thermally activated delayed fluorescence (TADF) enantiomers, namely /-PXZ-PT, are developed. Such a D-π*-A type structure completely suppresses the racemisation of the planar chirality, making it possible to prepare circularly polarized organic light-emitting diodes (CP-OLEDs) by vacuum deposition processing.

Helic[1]triptycene[3]arene: Synthesis, Complexation, and Formation of [2]Rotaxane Shuttle.

A new macrocyclic arene, helic[1]triptycene[3]arene , was conveniently synthesized in 37% yield by a one-pot reaction starting from 2,6-dimethoxyl-3,7-dihydroxymethyltriptycene. Macrocycle showed fixed conformation in solution and could form 1:1 complexes with a series of neutral guests, secondary ammonium salts, and tertiary ammonium salts in both solution and solid states. The association constants between and the neutral guests were between (1.

Pagoda[4]arene and -Pagoda[4]arene.

A new type of macrocyclic arenes, named pagoda[4]arene () and pagoda[4]arene (-), were conveniently synthesized by the TFA-catalyzed one-pot condensation of 2,6-dimethoxylanthracene and paraformaldehyde in dichloromethane at room temperature. and showed unique square pagoda structures and fixed conformations in solution and also exhibited strong blue fluorescence. Moreover, and - with deep and rich-electron cavities could not only encapsulate -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.