Chiral Macrocycles Research Articles

5]Helicene Based π-Conjugated Macrocycles with Persistent Figure-Eight and Möbius Shapes: Efficient Synthesis, Chiral Resolution and Bright Circularly Polarized Luminescence.

π-Conjugated chiral shape-persistent molecular nanocarbons hold great potential as chiroptical materials, though their synthesis remains a considerable challenge. Here, we present a simple approach using Suzuki coupling of a [5]helicene building block with various aromatic units, enabling the one-pot synthesis of a series of chiral macrocycles with persistent figure-eight and Möbius shapes. Single-crystal structures of 7 compounds were solved, and 22 enantiomers were separated by preparative chiral HPLC. A notable pyrene-bridged figure-eight macrocycle, with its rigid, fully π-conjugated and overcrowded structure, exhibited pure excimer emission and outstanding circularly polarized luminescence (CPL) properties, including a large dissymmetric factor (|glum|=3.8×10-2) and significant CPL brightness (BCPL=710.5 M-1cm-1). This method provides a versatile synthetic platform for producing various chiral D2-symmetric figure-eight macrocycles and singly or triply twisted Möbius macrocycles with C2 and D3 symmetry, offering tunable chiroptical properties for CPL applications.

5]Helicene Based π‐Conjugated Macrocycles with Persistent Figure‐Eight and Möbius Shapes: Efficient Synthesis, Chiral Resolution and Bright Circularly Polarized Luminescence

Abstractπ‐Conjugated chiral shape‐persistent molecular nanocarbons hold great potential as chiroptical materials, though their synthesis remains a considerable challenge. Here, we present a simple approach using Suzuki coupling of a [5]helicene building block with various aromatic units, enabling the one‐pot synthesis of a series of chiral macrocycles with persistent figure‐eight and Möbius shapes. Single‐crystal structures of 7 compounds were solved, and 22 enantiomers were separated by preparative chiral HPLC. A notable pyrene‐bridged figure‐eight macrocycle, with its rigid, fully π‐conjugated and overcrowded structure, exhibited pure excimer emission and outstanding circularly polarized luminescence (CPL) properties, including a large dissymmetric factor (|glum|=3.8×10−2) and significant CPL brightness (BCPL=710.5 M−1cm−1). This method provides a versatile synthetic platform for producing various chiral D2‐symmetric figure‐eight macrocycles and singly or triply twisted Möbius macrocycles with C2 and D3 symmetry, offering tunable chiroptical properties for CPL applications.

Anion Recognition-Directed Supramolecular Catalysis with Functional Macrocycles and Molecular Cages.

ConspectusThe development of supramolecular chemistry has provided a variety of host molecules and noncovalent tools for boosting catalytic processes, stimulating the emergence and advance of supramolecular catalysis, among which macrocyclic and cage-like compounds have attracted great attention due to their possession of an enzyme-mimetic cavity and recognition ability. While the privileged scaffolds such as crown ethers, cyclodextrins, cucurbiturils, calixarenes, and metal-coordinated cages have been widely used, their skeletons usually do not contain a directional binding site; binding and activation mainly rely on cation-associated interactions or hydrophobic effects. In this context, the recent advance of anion supramolecular chemistry has drawn our attention to developing an anion recognition-directed approach by using tailor-made functionalized macrocycles and cages. Anions are important widely existing species in both biological and chemical systems and play an important role in regulating the structure and function of enzymes. We envisioned that by taking advantage of anions, including their rich variety, diverse geometry, and multiple interaction sites, the sophisticated cooperation of multiple noncovalent interactions can be manipulated in a confined cavity for directing efficient and selective catalysis.Following this concept, we initiated our study by introducing typical thiourea H-bonding groups to design and synthesize a series of bis-thiourea macrocycles, especially chiral macrocycles, by incorporating chiral linkers. Taking advantage of the obtained strong, cooperative anion binding, a macrocycle-enabled counteranion trapping strategy was developed, which afforded greatly enhanced catalytic efficiency and excellent stereocontrol in acid-catalyzing reactions. Furthermore, inspired by sulfate-induced macrocyclic dimerization assembly, we built a substrate-induced assembly system, enabling an induced-fit cooperative activation network for efficient and enantioselective catalysis. In addition, anion recognition-driven chirality gearing with a more sophisticated trithiourea cage was revealed, which could provide a basis for implementing anion-triggered allosteric catalysis within the induced helical space. Not limited to hydrogen bonding, the emerging anion-π interactions were largely exploited. A series of triazine-based prism cages containing three V-shaped electron-deficient π-cavities were constructed, and their anion-π binding properties were studied. Based on this system, cooperative anion-π activation was established for driving highly efficient and selective catalysis, which paved a way to push anion-π interactions toward more practical and useful catalyst design.These results demonstrated that the anion-recognition direction can serve as a powerful, versatile approach for boosting highly efficient and selective supramolecular catalysis. It is feasible not only for employing exogenous anions (e.g., counteranion) as a handle but also for recognition and regulation of anionic active intermediates/transition states, from use in conventional H-bonding to emerging anion-π recognition.

Four-Membered Ring-Embedded Cycloarene Enabling Anti-Aromaticity and Ultra-Narrowband Emission.

The synthesis of fully fused π-conjugated cycloarenes embedded with nonbenzenoid aromatics is challenging. In this work, the first example of four-membered ring-embedded cycloarene (MF2) was designed and synthesized in single-crystal form by macrocyclization and ring fusion strategies. For comparison, single bond-linked chiral macrocycle MS2 without two fused four-membered rings and its linear-shaped polycyclic benzenoid monomer L1 were also synthesized. The pronounced anti-aromaticity of four-membered rings significantly adjusts the electronic structures and photophysical properties of cycloarene, resulting in an enhancement of the photoluminescence quantum yield (PLQY) from 10.66 % and 10.74 % for L1 and MS2, respectively, to 54.05 % for MF2, which is the highest PLQY among the reported cycloarenes. Notably, owing to the embedded anti-aromatic four-membered rings that reduce structural displacements, MF2 exhibits an ultra-narrowband emission with a single-digit full-width at half-maximum (FWHM) of only 7 nm (0.038 eV), which sets a new record among all reported organic narrowband luminescent molecules, and represents the first example of ultra-narrowband emission in conventional polycyclic aromatic hydrocarbons (PAHs) devoid of heteroatoms.

Synthesis and spectroscopic studies of triazole-based macroheterocycles containing eudesmane-type sesquiterpenoid moieties

Chiral recognition is one of the most important and fascinating areas in supramolecular chemistry. Chiral macrocycles, especially chiral macrocyclic hosts, having stable structures, adjustable internal cavities to encapsulate and complexation have been developed during the last decade. Attention has been paid on the synthesis of covalently linked of rigid units on the side chain of macrocycles with active binding motifs. In this study, new synthetic protocols has been developed for preparation of optically active triazole-based macrocyclic compounds in which eudesmane-type sesquiterpene lactones act as pendent moieties by the implementation of the copper(I)-catalyzed azid-alkyne cycloaddition strategies. The described protocols provided mild reaction conditions, high yields and high atom- and step-economy. New macrocycles with hanging dihydroisoalantolactone units, different combinations of heteroatoms, and ring sizes in the range of 16–36 atoms were characterized by NMR and UV–vis spectroscopy and mass spectrometry analysis. The molecular structures and intermolecular interactions of two new macrocyclic compounds were elucidated using single-crystal X-ray crystallography. Upon addition of Mg(II) or Zn(II) cations to these novel ligands, using titration experiments we observed the formation of 1:1 (16:Mg2+) complexes and 1:1 to 2:1 (16:Zn2+) complexes, respectively, according to stoichiometry. The result suggests that dihydriisoalantolactone and triazole units within the molecules formed complexes with Mg (II) and Zn (II) ions in solution.

Synthesis and characterization of a chiral spirobifluorene cyclic hexamer

Abstract A new chiral macrocycle 1-[6], consisting of six chiral spirobifluorene units linked in a cyclic arrangement, was successfully synthesized via a homo-coupling of the corresponding acyclic trimer. Notably, this chiral cyclic hexamer exhibited flexibility in solution, and both low-temperature nuclear magnetic resonance (NMR) experiments and density functional theory (DFT) calculations suggest that its stable structure is not the hexagonal D6-symmetric structure but rather the figure-eight-shaped D2-symmetric structure. In this D2-symmetric structure, the opposing bifluorenyl units are π-stacked, and it is suggested that this π-stacked region undergoes rapid dissociation and reformation at room temperature. The HOMO is distributed over the π-stacked region, with a HOMO-LUMO gap of 4.02 eV. The macrocycle exhibited strong violet fluorescence. The absorption dissymmetry factor |gabs| was 7.4 × 10−3, which is larger compared to the series of chiral smaller macrocycles 1-[n] (n = 3 to 5). Additionally, the CPL efficiency, indicated by a BCPL value of 189 M−1 cm−1, is relatively high among chiral organic luminescent molecules.

Recent Advances on Catalytic Atroposelective Synthesis of Planar‐Chiral Macrocycles

AbstractPlanar‐chiral skeletons widely exist in natural products, bioactive compounds, and other functional molecules. Although significant progress has been made in the field of asymmetric synthesis of centrally or axially chiral molecules over the past years, enantioselective constructing of planar chirality is still a big obstacle and numerous efforts have been made in this field. Previous works have mainly focused on the assembly of planar‐chiral [2,2]‐paracyclophanes and metallocenes. This Minireview describes recent advancements in asymmetric catalytic synthesis of planar‐chiral macrocycles, including ansa chain construction, plane formation and asymmetric transformation strategies. It is anticipated that this Minireview will sever as a source of inspiration for developing new unconventional procedures for access to planar‐chiral skeletons.

Recent Advances on Catalytic Atroposelective Synthesis of Planar-Chiral Macrocycles.

Planar-chiral skeletons widely exist in natural products, bioactive compounds, and other functional molecules. Although significant progress has been made in the field of asymmetric synthesis of centrally or axially chiral molecules over the past years, enantioselective constructing of planar chirality is still a big obstacle and numerous efforts have been made in this field. Previous works have mainly focused on the assembly of planar-chiral [2,2]-paracyclophanes and metallocenes. This Minireview describes recent advancements in asymmetric catalytic synthesis of planar-chiral macrocycles, including ansa chain construction, plane formation and asymmetric transformation strategies. It is anticipated that this Minireview will sever as a source of inspiration for developing new unconventional procedures for access to planar-chiral skeletons.

Chiral Macrocycles for Enantioselective Recognition.

The efficient synthesis of chiral macrocycles with highly enantioselective recognition remains a challenge. We have addressed this issue by synthesizing a pair of chiral macrocycles, namely, R/S-BINOL[2], achieving total isolated yields of up to 62% through a two-step reaction sequence. These macrocycles are readily purified by column chromatography over silica gel without the need for chiral separation, thus streamlining the overall synthesis. R/S-BINOL[2] demonstrated enantioselective recognition toward chiral ammonium salts, with enantioselectivity (KS/KR) values reaching up to 13.2, although less favorable separations were seen for other substrates. R/S-BINOL[2] also displays blue circularly polarized luminescence with a |glum| value of up to 2.2 × 10-3. The R/S-BINOL[2] macrocycles of this study are attractive as chiral hosts in that they both display enantioselective guest recognition and benefit from a concise, high-yielding synthesis. As such, they may have a role to play in chiral separations.

Four‐Membered Ring‐Embedded Cycloarene Enabling Anti‐Aromaticity and Ultra‐Narrowband Emission

AbstractThe synthesis of fully fused π‐conjugated cycloarenes embedded with nonbenzenoid aromatics is challenging. In this work, the first example of four‐membered ring‐embedded cycloarene (MF2) was designed and synthesized in single‐crystal form by macrocyclization and ring fusion strategies. For comparison, single bond‐linked chiral macrocycle MS2 without two fused four‐membered rings and its linear‐shaped polycyclic benzenoid monomer L1 were also synthesized. The pronounced anti‐aromaticity of four‐membered rings significantly adjusts the electronic structures and photophysical properties of cycloarene, resulting in an enhancement of the photoluminescence quantum yield (PLQY) from 10.66 % and 10.74 % for L1 and MS2, respectively, to 54.05 % for MF2, which is the highest PLQY among the reported cycloarenes. Notably, owing to the embedded anti‐aromatic four‐membered rings that reduce structural displacements, MF2 exhibits an ultra‐narrowband emission with a single‐digit full‐width at half‐maximum (FWHM) of only 7 nm (0.038 eV), which sets a new record among all reported organic narrowband luminescent molecules, and represents the first example of ultra‐narrowband emission in conventional polycyclic aromatic hydrocarbons (PAHs) devoid of heteroatoms.

Synthesis of Inherently Chiral Homo-heteracalixaromatics.

There is a resurgence of research interest in inherently chiral calixarenes and heteracalixaromatics. However, the examples of macrocyclic ring-expanded homocalixarenes and heterocalixaromatics of inherent chirality are not known. Here we report an efficient method to construct inherently chiral N2,O2-linked homo-heteracalixaromatics from reductive amination reactions between bis-aldehydes and aliphatic diamines. Examples of post-macrocyclization derivatization were also demonstrated. Enantiomers were obtained from resolution and did not undergo racemization at an elevated temperature. This study provides a new strategy to design novel and functional inherently chiral macrocycles that have potential applications in supramolecular chemistry.

Facile synthesis of a new chiral polyimine macrocycle and its application for enantioseparation in high-performance liquid chromatography

Macrocyclic compounds such as crown ethers and cyclodextrins play an important role in the field of chromatography and show excellent separation performance. The design of simple and convenient methods for the efficient synthesis of novel chiral macrocycles for chromatographic separation is of great significance. In this work, a novel chiral polyimine macrocycle (PIMC) was designed and synthesized by the simply one-step reaction of 2,6-diformyl-4-tert-butylphenol with (S)-(-)-1,2-propanediamine. Then, it was bonded onto silica by the thiol-ene click reaction to construct a new chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC). The chiral separation performance of the proposed CSP was examined by separating various racemates in the normal-phase (NP) and reversed-phase (RP) HPLC. In total, twelve and nine racemates, including ethers, esters, amines, alcohols, organic acids, ketones, and epoxides, were separated to varying degrees via NP-HPLC and RP-HPLC, respectively, Moreover, the CSP offered good chiral separation complementarity to Chiralcel OD-H and Chiralpak AD-H columns for resolution of these test racemates, and it can separate several racemic compounds that either cannot be separated or cannot be separated well be separated by the two commercially available columns. After the column was used for hundreds of injections, the relative standard deviations of the retention time and resolution were below 0.56 % and 0.45 %, respectively, showing the good reproducibility and stability of the CSP. This study provides a simple and convenient approach to synthesize a novel chiral macrocycle and CSP and also indicates the broad application prospects of such chiral PIMCs in HPLC chiral separation.

Preparation and evaluation of a 1,1′-bi-2-naphthol-based chiral macrocycle bonded silica chiral stationary phase for high performance liquid chromatography

Macrocycles play vital roles in supramolecular chemistry and chromatography. 1,1′-Bi-2-naphthol (BINOL)-based chiral polyimine macrocycles are an emerging class of chiral macrocycles that can be constructed by one-step aldehyde-amine condensation of BINOL derivatives with other building blocks. These macrocycles exhibit good characteristics, such as facile preparation, rigid cyclic structures, multiple chiral centers, and defined molecular cavities, that make them good candidates as new chiral recognition materials for chromatographic enantioseparations. In this study, a BINOL-based [2+2] chiral polyimine macrocycle was synthesized by one-step condensation of enantiopure (S)-2,2′-dihydroxy-[1,1′-binaphthalene]-3,3′-dicarboxaldehyde with (1R,2R)-1,2-diaminocyclohexane. The product was modified with 5-bromo-1-pentene and then attached to thiolated silica using click chemistry to construct a new chiral stationary phase (CSP). The enantioselectivity of the new CSP was explored by separating various racemates under normal phase (NP) and reversed phase (RP) high performance liquid chromatography (HPLC). Thirteen racemates and eight racemates were enantioseparated under the two separation modes, respectively, including chiral alcohols, phenols, esters, ketones, amines, and organic acids. Among them, nine racemates achieved baseline separation under NP-HPLC and seven racemates achieved baseline separation under RP-HPLC. High resolution separation was observed with benzoin (Rs = 5.10), epinephrine (Rs = 4.98), 3-benzyloxy-1,2-propanediol (Rs = 4.42), and 4,4′-dimethylbenzoin (Rs = 4.52) in NP-HPLC, and with 4-methylbenzhydrol (Rs = 4.72), benzoin ethyl ether (Rs = 3.79), 1-phenyl-1-pentanol (Rs = 3.68), and 1-(3-bromophenyl)ethanol (Rs = 3.60) in RP-HPLC. Interestingly, the CSP complemented Chiralcel OD-H, Chiralpak AD-H, and CYCLOBOND I 2000 RSP columns for resolution of these test racemates, separating several racemic compounds that could not be well separated by the three commercially available columns. The influences of injected sample amount on separation were also evaluated. It was found that the column exhibited excellent stability and reproducibility after hundreds of injections, and the relative standard deviations (n = 5) of the retention time and resolution were less than 0.49% and 0.69%, respectively. This study indicates that the BINOL-based chiral macrocycle has great potential for HPLC enantioseparation.

Enantiomerically Resolvable Inherent Chirality Induced by Strong Para-Steric Hindrance in Cycloparaphenylene-Based Carbon Nanohoops.

The chemical modification of the achiral carbon nanohoops to break the symmetry will result in inherently chiral structures with interesting optical properties. Herein, we report two novel π-extended chiral macrocycles, cyclo[10]paraphenylene-pyrene ([10]CPP-2Pyrene) and cyclo[10]paraphenylene-hexa-peri-hexabenzocoronene ([10]CPP-2HBC). The large substituents on the nanohoop peripheries effectively prevented free rotation and the racemization process. The conformation of each enantiomer is stable enough to be resolved by recycling HPLC.

BINOL-Based Chiral Macrocycles and Cages.

Chirality, a fundamental principle in chemistry, biology, and medicine, is prevalent in nature and in organisms. Chiral molecules, such as DNA, RNA, and proteins, are crucial in biomolecular synthesis, as well as in the development of functional materials. Among these, 1,1'-binaphthyl-2,2'-diol (BINOL) stands out for its stable chiral configuration, versatile functionality, and commercial availability. BINOL is widely employed in asymmetric catalysis and chiral materials. This review mainly focuses on recent research over the past five years concerning the use of BINOL derivatives for constructing chiral macrocycles and cages. Their contributions to chiral luminescence, enantiomeric separation, transmembrane transport, and asymmetric catalysis were examined.

Polycationic Open‐Shell Cyclophanes: Synthesis of Electron‐Rich Chiral Macrocycles, and Redox‐Dependent Electronic States

Abstractπ‐Conjugated chiral nanorings with intriguing electronic structures and chiroptical properties have attracted considerable interests in synthetic chemistry and materials science. We present the design principles to access new chiral macrocycles (1 and 2) that are essentially built on the key components of main‐group electron‐donating carbazolyl moieties or the π‐expanded aza[7]helicenes. Both macrocycles show the unique molecular conformations with a (quasi) figure‐of‐eight topology as a result of the conjugation patterns of 2,2’,7,7’‐spirobifluorenyl in 1 and triarylamine‐coupled aza[7]helicene‐based building blocks in 2. This electronic nature of redox‐active, carbazole‐rich backbones enabled these macrocycles to be readily oxidized chemically and electrochemically, leading to the sequential production of a series of positively charged polycationic open‐shell cyclophanes. Their redox‐dependent electronic states of the resulting multispin polyradicals have been characterized by VT‐ESR, UV/Vis‐NIR absorption and spectroelectrochemical measurements. The singlet (ΔES‐T=−1.29 kcal mol−1) and a nearly degenerate singlet‐triplet ground state (ΔES−T(calcd)=−0.15 kcal mol−1 and ΔES−T(exp)=0.01 kcal mol−1) were proved for diradical dications 12+2⋅ and 22+2⋅, respectively. Our work provides an experimental proof for the construction of electron‐donating new chiral nanorings, and more importantly for highly charged polyradicals with potential applications in chirospintronics and organic conductors.

Polycationic Open-Shell Cyclophanes: Synthesis of Electron-Rich Chiral Macrocycles, and Redox-Dependent Electronic States.

π-Conjugated chiral nanorings with intriguing electronic structures and chiroptical properties have attracted considerable interests in synthetic chemistry and materials science. We present the design principles to access new chiral macrocycles (1 and 2) that are essentially built on the key components of main-group electron-donating carbazolyl moieties or the π-expanded aza[7]helicenes. Both macrocycles show the unique molecular conformations with a (quasi) figure-of-eight topology as a result of the conjugation patterns of 2,2',7,7'-spirobifluorenyl in 1 and triarylamine-coupled aza[7]helicene-based building blocks in 2. This electronic nature of redox-active, carbazole-rich backbones enabled these macrocycles to be readily oxidized chemically and electrochemically, leading to the sequential production of a series of positively charged polycationic open-shell cyclophanes. Their redox-dependent electronic states of the resulting multispin polyradicals have been characterized by VT-ESR, UV/Vis-NIR absorption and spectroelectrochemical measurements. The singlet (ΔES-T=-1.29 kcal mol-1) and a nearly degenerate singlet-triplet ground state (ΔES-T(calcd)=-0.15 kcal mol-1 and ΔES-T(exp)=0.01 kcal mol-1) were proved for diradical dications 12+2⋅ and 22+2⋅, respectively. Our work provides an experimental proof for the construction of electron-donating new chiral nanorings, and more importantly for highly charged polyradicals with potential applications in chirospintronics and organic conductors.

Macrocycle‐Based Charge Transfer Cocrystals with Dynamically Reversible Chiral Self‐Sorting Display Chain Length‐Selective Vapochromism to Alkyl Ketones

AbstractChirality‐driven self‐sorting plays an essential role in controlling the biofunction of biosystems, such as the chiral double‐helix structure of DNA from self‐recognition by hydrogen bonding. However, achieving precise control over the chiral self‐sorted structures and their functional properties for the bioinspired supramolecular systems still remains a challenge, not to mention realizing dynamically reversible regulation. Herein, we report an unprecedented saucer[4]arene‐based charge transfer (CT) cocrystal system with dynamically reversible chiral self‐sorting synergistically induced by chiral triangular macrocycle and organic vapors. It displays efficient chain length‐selective vapochromism toward alkyl ketones due to precise modulation of optical properties by vapor‐induced diverse structural transformations. Experimental and theoretical studies reveal that the unique vapochromic behavior is mainly attributed to the formation of homo‐ or heterochiral self‐sorted assemblies with different alkyl ketone guests, which differ dramatically in solid‐state superstructures and CT interactions, thus influencing their optical properties. This work highlights the essential role of chiral self‐sorting in controlling the functional properties of synthetic supramolecular systems, and the rarely seen controllable chiral self‐sorting at the solid‐vapor interface deepens the understanding of efficient vapochromic sensors.

Macrocycle-Based Charge Transfer Cocrystals with Dynamically Reversible Chiral Self-Sorting Display Chain Length-Selective Vapochromism to Alkyl Ketones.

Chirality-driven self-sorting plays an essential role in controlling the biofunction of biosystems, such as the chiral double-helix structure of DNA from self-recognition by hydrogen bonding. However, achieving precise control over the chiral self-sorted structures and their functional properties for the bioinspired supramolecular systems still remains a challenge, not to mention realizing dynamically reversible regulation. Herein, we report an unprecedented saucer[4]arene-based charge transfer (CT) cocrystal system with dynamically reversible chiral self-sorting synergistically induced by chiral triangular macrocycle and organic vapors. It displays efficient chain length-selective vapochromism toward alkyl ketones due to precise modulation of optical properties by vapor-induced diverse structural transformations. Experimental and theoretical studies reveal that the unique vapochromic behavior is mainly attributed to the formation of homo- or heterochiral self-sorted assemblies with different alkyl ketone guests, which differ dramatically in solid-state superstructures and CT interactions, thus influencing their optical properties. This work highlights the essential role of chiral self-sorting in controlling the functional properties of synthetic supramolecular systems, and the rarely seen controllable chiral self-sorting at the solid-vapor interface deepens the understanding of efficient vapochromic sensors.

Circularly Polarized Luminescent π‐Conjugated Chiral Nanorings and Nanobelts

AbstractMolecular chirality plays a pivotal role across the disciplines of chemical and physical sciences, as well as holding significant implications in the realms of medicine and technology. Chiral macrocycles have attracted recent interests in synthetic chemistry, material science, and supramolecular chemistry. Due to the cyclic arrangements of stereogenic elements or special orientations confined in the rigid structures, π‐conjugated chiral macrocycles are expected to be highly luminescent, and configurationally stable, and thus serve to develop high‐performance chiroptical materials. Given the rapid progress achieved in this new area in recent years, it is significant to highlight new concepts and breakthroughs. This minireview will offer the overview of a wide range of π‐conjugated chiral macrocycles from traditional molecules which include the axially, helically, and planar chiral skeletons to the new chiral nanobelts with a focus on the structure‐function relationship between chiral molecules and the unique chiroptical properties.