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The unique structure of [2.2]paracyclophane (PCP) with its rigidity, stability, and planar chirality has gained significant attention in polymer and material research. In this work, the incorporation of amino‐functionalized PCPs within polymers of intrinsic microporosity (PIMs) is reported for the first time. Three different PCP‐PIMs were prepared via a Tröger's base formation mechanism, and their structures characterized via solid‐state NMR, MALDI‐TOF, and SEM. Their porosity was evaluated using gas adsorption (N2 and CO2) based on theoretical calculations such as Brunauer–Emmett–Teller (BET), NLDFT pore size distribution (PSD) and ideal IAST CO2/N2 selectivity (15/85), a crucial separation when considering the capture of CO2 from flue gas. The surface areas were found to be between 200–230 m2 g−1 while the selectivity for CO2/N2 ranged from 46 to 70. [ABSTRACT FROM AUTHOR]

The prototypical example of a (cyclo)phane, [2.2]paracyclophane (PCP), has proven to be a versatile stereogenic moiety within the design of circularly polarized thermally activated delayed fluorescence (CP‐TADF) emitters; however, the exploration of other cyclophanes within CP‐TADF emitter design has been largely neglected. Here, a comparative study of the photophysical and optoelectronic properties of two cyclophane emitters, (1,7)tBuCzpPhTrz and its isomer (1,4)tBuCzpPhTrz, is presented. The carbazolophane‐triazine compound (1,7)tBuCzpPhTrz, obtained via an unprecedented intramolecular rearrangement, is the first example of a planar chiral TADF emitter deviating from the PCP scaffold. Significant geometrical change of the enclosed carbazole in (1,7)tBuCzp results in an attenuation of the donor strength, while the merits of rigidity and steric bulk remain. In particular, the full width at half maximum (FWHM) of the photoluminescence spectrum in toluene of (1,7)tBuCzpPhTrz is reduced by 34% and blue‐shifted by 20 nm compared to that of (1,4)tBuCzpPhTrz. In doped films, the compounds reach high photoluminescence quantum yields (ΦPL) of 91 and 81%, respectively. The chiroptical properties reveal dissymmetry factors |gPL| of up to 5 × 10−4. These results demonstrate the impact of the cyclophane for the development of CP‐TADF materials and add to the currently limited scope of available planar chiral donors. [ABSTRACT FROM AUTHOR]

[2.2]Paracyclophanes ([2.2]PCs) with substituents at specific positions possesses planar chirality and stands as a promising building unit for the development of chiroptical materials associated with polarized light. However, one of the easily accessible starting materials, bromo‐substituted [2.2]PC, shows low reactivity, and effective methods for π‐extension of planar chiral [2.2]PC are limited. Herein, an effective π‐extension method has established for chiral [2.2]PC with four substitutions from 4,7,12,15‐tetrabromo[2.2]PC. This has led to tetrakis(trimethylsilylphenyl)‐[2.2]PC that serves as a versatile building resource for radial‐type chiral π‐conjugated compounds with a [2.2]PC core. In this study, synthesizing compounds are further succeeded with the introduction of carbazole (Cbz4‐[2.2]PC and tBuCbz4‐[2.2]PC) and investigated their chiroptical properties and chiral induction ability in achiral π‐conjugated polymers. A thin film of [Poly[9,9‐dioctylfluorenyl‐2,7‐diyl)‐alt‐(benzo[2,1,3]thiadiazol‐4,7‐diyl)]] (F8BT) with 3wt% Cbz4‐[2.2]PC prepared by spin‐coating exhibits circularly polarized luminescence (CPL) properties with a high dissymmetry factor (|glum| = 0.01), which is much higher than that of Cbz4‐[2.2]PC in CH2Cl2 solution. By contrast, the doped film of F8BT with 3wt% tBuCbz4‐[2.2]PC exhibited only weak CPL properties. In addition, these chiral compounds show facile redox properties owing to the presence of carbazole units. Furthermore, Cbz4‐[2.2]PC undergoes electropolymerization to produce an insoluble thin film on the electrode. [ABSTRACT FROM AUTHOR]

In this study, featuring di[2.2]paracyclophane (DpCp) amine derivatives as electron donors and 4‐(4,6‐diphenyl‐1,3,5‐triazin‐2‐yl)phenyl (Trz) as the electron acceptor, four thermally activated delayed fluorescence (TADF) molecules are disclosed. The C2 symmetric molecules, DpCpN‐Trz and DpCpCz‐Trz, bearing a chair‐like planar chiral di[2.2]paracyclophane moiety, are obtained as optically pure enantiomers (R/S)‐C‐DpCpN‐Trz and (R/S)‐C‐DpCpCz‐Trz. And the compounds B‐DpCpN‐Trz and B‐DpCpCz‐Trz with a bridge‐like di[2.2]paracyclophane skeleton are meso‐compounds, thus without optically activity. All emitters show blue emissions peaking from 464 to 485 nm, accompanied by high photoluminescence quantum efficiency (up to 93%). The enantiomers (R/S)‐C‐DpCpN‐Trz and (R/S)‐C‐DpCpCz‐Trz exhibit symmetric circularly polarized photoluminescence spectra with dissymmetry factors (|gPL|) ranging from 3.8 × 10−4 to 6.7 × 10−4 in toluene and films. The organic light‐emitting diodes (OLEDs) fabricated with these emitters achieve maximum external quantum efficiencies of up to 19.5%. Notably, the circularly polarized OLEDs (CP‐OLEDs) with (R/S)‐C‐DpCpN‐Trz and (R/S)‐C‐DpCpCz‐Trz demonstrate |gEL| factors of up to 7.6 × 10−4. This study demonstrates a feasible way to design TADF materials and enantiomers by incorporating DpCp derivatives for CP‐OLEDs. [ABSTRACT FROM AUTHOR]

Many of the functions and features of practically useful materials are the province of molecular‐level chemistry and their modulation at different length‐scale. This report illustrates the molecular‐level chemistry behind functions and features of the [2.2]paracyclophane‐based materials with a particular focus on the most recent explorations on through‐space conjugated small‐molecule organic emitters, π‐stacked macrocyclic molecules and polymers, poly(p‐phenylenevinylene)s featuring well‐defined donor‐acceptors sequence control, and surface engineering of technologically‐relevant parylenes that finds broad applications across the field of chemical science and technology. This report largely deals with the potential and opportunities associated with molecular features and functions of planar chirality, conformational behaviors, strain‐induced non‐planarity of the aromatics, the profound impacts of through‐space conjugation and π‐electron interactions/delocalization on optoelectronic properties of the π‐conjugated organic emitters, polymers and extended structures consisting of cyclophanes. A special focus is put on the concept of supramolecular polymers using chemically‐programmed chiral cyclophanes via non‐covalent stacking and controlled conformational arrangements. Illustrating cyclophane as precursors/monomers and fabrication strategies for their incorporation in structurally‐controlled (poly(p‐xylylene)s formed via chemical vapor deposition polymerization and post‐deposition fabrication for interface engineering is described. Demonstrating a rather different approach of electronically‐dictated ring‐opening metathesis polymerization employing strained cyclophane‐diene precursors that generate conjugated poly(p‐phenylenevinylene)s with well‐defined (i.e., low dispersity) and donor‐acceptor sequence control is also discussed. This report will serve as an indispensable one‐stop reference for organic, and polymer chemists, as well as material scientists working with cyclophanes for research innovations. [ABSTRACT FROM AUTHOR]

Optically active A‐shaped cyclic molecules are synthesized by incorporating a planar chiral [2.2]paracyclophane unit to form a helical structure. These molecules exhibit large molar absorption coefficients, moderate photoluminescence (PL) quantum efficiencies, and high circularly polarized luminescence (CPL) anisotropy factors, resulting in high CPL brightness values (BCPL values). According to the time‐dependent density functional theory (TD‐DFT) theoretical studies, extended π‐conjugated moieties act as light‐harvesting units, and emissions occur from the helical skeletons. The TD‐DFT calculations reproduce the experimentally determined absorption, PL, circular dichroism, and CPL properties of the A‐shaped cyclic molecules. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals (vdW) semiconductors play a key role in developing nanoscale nonlinear optical devices. 2D Ruddlesden-Popper lead halide perovskites (RPPs) expand the potential of using 2D vdW semiconductors in nonlinear optical applications because they exhibit electrically switchable and chiral second-order optical nonlinearity originating from the emergence of ferroelectricity and chirality. However, electrically switchable chiral nonlinear optics has not yet been realized because of the difficulty in electrically manipulating chiral structures. Here, we demonstrate that chiral second-harmonic generation (SHG) can be electrically induced and switched in an achiral biaxial ferroelectric 2D RPP. We observe reversible and continuous electrical switching of SHG circular dichroism and large nonlinear chiroptical activity. Polarization-resolved SHG imaging reveals that electrical poling induces the ferroelectric multidomain structure arising from the biaxial nature of the material, and the planar chirality appears. Our findings show a simple electrical control of the nonlinear chiroptical responses and establish chiral nonlinear optics based on ferroelectric 2D RPPs. [ABSTRACT FROM AUTHOR]

An unprecedented chemodivergent strategy for parallel kinetic resolution (PKR) is disclosed through which two planar chiral products bearing different structures were simultaneously afforded with opposite stereoselectivities. Two achiral esters are activated by one single chiral N‐heterocyclic carbene (NHC) catalyst to react with the different enantiomers of the racemic imine substrate in a parallel fashion. Two products bearing distinct structures and opposite stereoselectivities are respectively afforded from the same reaction system in good to excellent yields, enantio‐ and diastereoselectivities. Control experiments and kinetic studies are carried out to probe the kinetic and dynamic properties during the reaction progress. The planar chiral pyridine and lactam products show interesting applications in both asymmetric synthesis and pesticide development. [ABSTRACT FROM AUTHOR]

Resonant dielectric planar structures can interact selectively with light of particular helicity thus providing an attractive platform for “chiral flat optics”. The absence of mirror‐symmetry planes defines geometric chirality, and it remains the main condition for achieving strong circular dichroism. For planar optical structures such as photonic‐crystal slabs and metasurfaces, breaking the out‐of‐plane mirror symmetry is especially challenging, as it requires to fabricate meta‐atoms with a tilt, variable height, or vertically shifted positions. Although transparent substrates formally break out‐of‐plane mirror symmetries, their optical effect is typically subtle being rarely considered for enhancing optical chirality. Here it is revealed that low‐refractive‐index substrates can induce up to maximum intrinsic optical chirality in otherwise achiral metastructures so that the transparency to waves of one helicity is combined with resonant blocking of waves of the opposite helicity. This effect originates from engineering twisted photonic eigenstates of different parities. The perturbation analysis developed in terms of the resonant‐state expansion reveals how the eigenstate coupling induced by a substrate gives rise to a pair of chiral resonances of opposite handedness. The general theory is confirmed by the specific examples of light transmission in the normal and oblique directions by a rotation‐symmetric photonic‐crystal slab placed on different transparent substrates. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of functionalized three-dimensional benzophenone analogues derived from [2.2]paracyclophane (pCp). The potential use of these compounds as photocatalysts is disclosed. Benzophenone and its derivatives are well-known photoactive compounds that have been extensively employed over the years as catalysts to promote a variety of transformations activated by light. The development of differently substituted three-dimensional versions of such compounds may significantly expand the range of their applications in photocatalysis. Exploitation of the planar chirality of substituted paracyclophanes may also lead to significant innovations in different fields. [2.2]Paracyclophane-based benzophenone derivatives incorporating reactive ester or amide functions at their pseudo-gem position are successfully prepared in a selective manner. Examples of both racemic and enantiopure compounds are reported. As a proof of concept, the catalytic activities of the newly synthesized molecules are compared to that of benzophenone in a known photooxidation reaction. [ABSTRACT FROM AUTHOR]

Macrolactonization is a challenging process where high dilution and temperatures can extend reaction times and promote reagent degradation. Biocatalysis is a versatile strategy for synthesis but not traditionally associated within the toolbox of organic chemists for macrocyclization. Macrolactonization has been investigated using modern methods employing both catalysis and stoichiometric activation strategies on 20 different substrates with differing ring sizes and types (cyclophanes, macrolactones, macrodiolides) and structural features at the reaction site (central vs. planar chirality; primary vs. secondary alcohols). The data demonstrates that of all protocols examined, the biocatalytic route was superior, providing the highest average yields across all classes of macrocycles studied. From the stoichiometric activation strategies investigated, the Yamaguchi macrolactonization was the most versatile in terms of ring size and nature. Despite the advantages of biocatalytic macrolactonization, advances in developing supported, versatile non-enantioselective lipases would actually represent a useful tool in molecular synthesis. [ABSTRACT FROM AUTHOR]

We present an improved and convenient synthesis of [2.2]paracyclophane‐imidazoline N,O‐ligands with central and planar chirality in seven steps starting from [2.2]paracyclophane. The utility of these ligands in organozinc additions to aldehydes is described. The asymmetric ethylation of aldehydes proceeded with enantioselectivities of up to 97 % ee, while the asymmetric arylation of aldehydes gave up to 95 % ee (R) and 82 % ee (S) using (S,S,SP)‐UCD‐Imphanol and (S,S,RP)‐UCD‐Imphanol, respectively. [ABSTRACT FROM AUTHOR]

It has been known since the 1990s that the introduction of a ferrocenyl–type substituent into compounds with proven biological activity can improve their properties. More recently, it was also shown that a carbon bridge connecting the two cyclopentadienyl rings in ferrocene derivatives could enhance the biological properties of the new compounds compared to those without them. However, the synthesis of ferrocenes with this additional linker, known as ansa–ferrocenes, is more difficult due to advanced synthetic protocols and the phenomenon of planar chirality in ring–substituted compounds. As a result, research into the formation of hybrids, conjugates and other ansa–ferrocene derivatives has not been widely conducted. This review discusses the potential biological properties of these units, covering scientific articles published between 1980 and 2024. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We report herein a series of macrocycles in which the densely π‐stacked charge‐transfer (CT) donor/acceptor with naphthalenediimides (NDIs) or perylene diimide (PDI) as acceptor moiety pairing various donor moieties are locked by covalent bond. The X‐ray crystallography of C8BDT‐NDI reveals a short intramolecular π‐stacking distance around 3.4 Å and the existence of intermolecular donor/acceptor π‐stacking (3.7 Å). The intramolecular CT is highly dependent on the electron‐donating ability of donor moiety and replacing carbazole (C8KZ) with benzo[1,2‐b:4,5‐b′]dithiophene (C8BDT) or dihydroindolo[3,2‐b]indole (C8DN) redshift CT absorption into NIR region. Notably, both C8BDT‐NDI and C8DN‐NDI demonstrate excellent photothermal performance, which is a result of the active non‐radiative pathways. Interestingly, the different molecular symmetry between donor and acceptor moiety in cyclophanes endow C8BDT‐NDI and C8DN‐NDI with intrinsic planar chirality. The enantiomeric C8BDT‐NDI shows chiral selectivity for incident light, i.e., when irradiated by left‐circularly polarized light, (R)‐C8BDT‐NDI is more sensitive and a higher maximum stable temperature is achieved. While, enantiomeric C8DN‐NDI pack with different orientations forming M‐ and P‐handedness helix, respectively, demonstrating molecular planar chirality being transferred and amplified through molecular assembly. These results provide insight into the intramolecular charge transfer in enforced D/A π‐stacks in which CT interactions and planar chirality would be engineered through structural control. [ABSTRACT FROM AUTHOR]

A pair of racemic oxacalix[4]arenes featuring planar chirality and a mesomer with a symmetric plane were conveniently synthesized under mild conditions via a one‐pot dynamic SNAr reaction and separated in 20 % and 49 % yields, respectively. X‐ray single crystal analyses confirmed their structures unambiguously. The racemic mixture could further be resolved using HPLC on a chiral column. Time‐dependent products distribution and interconversion between products with CsF as a catalyst were revealed by 1H NMR studies, convincing the dynamic nature of SNAr reaction. [ABSTRACT FROM AUTHOR]

Pd(II)‐catalyzed enantioselective C−H activation has emerged as a versatile platform for constructing point, axial, and planar chirality. Herein, we present an unexpected discovery of a Pd‐catalyzed enantioselective cascade β,γ‐methylene C(sp3)−H diarylation of free carboxylic acids using bidentate chiral mono‐protected amino thioether ligands (MPAThio), enabling one‐step synthesis of a complex chiral 9,10‐dihydrophenanthrene scaffolds with high enantioselectivity. In this process, two methylene C(sp3)−H bonds and three C(sp2)−H bonds were activated, leading to the formation of four C−C bonds and three chiral centers in one pot. A plausible catalytic pathway starts with enantioselective β,γ‐dehydrogenation to form chiral β,γ‐cyclohexene. Intriguingly, this olefin serves as a norbornene‐type reagent (presumably assisted by the carboxyl directing effect), relaying two successive Catellani arylation reactions and a C−H arylation reaction to furnish chiral 9,10‐dihydrophenanthrenes along with meta‐selective homocoupling products of iodoarene. [ABSTRACT FROM AUTHOR]

The building blocks-based molecular network (BBMN) strategy was applied to the phytochemical investigation of Cleistocalyx operculatus , leading to the targeted isolation of eighteen novel cinnamoylphloroglucinol-terpene adducts (CPTAs) with diverse skeleton types (cleistoperones A–R, 1 – 18). Their structures including absolute configurations were determined by extensive spectroscopic methods, quantum chemical calculations, and single-crystal X-ray crystallographic experiments. Cleistoperone A (1), consisting of a cinnamoylphloroglucinol motif and two linear monoterpene moieties, represents an unprecedented macrocyclic CPTA, whose densely functionalized tricyclo[15.3.1.03,8]heneicosane bridge ring skeleton contains an enolizable β , β ′-triketone system and two different kinds of stereogenic elements (including five point and three planar chiralities). Cleistoperones B and C (2 and 3) are two new skeletal CPTAs with an unusual coupling pattern between the (nor)monoterpene moiety and the cinnamoyl chain of the cinnamoylphloroglucinol unit. Cleistoperone D (4) possesses an unprecedented cage-like 6/6/6/4/6-fused heteropentacyclic scaffold. The plausible biosynthetic pathways for 1 – 18 were also proposed. Notably, compounds 1 , 4 , 7 , 8 , and 18 exhibited significant antiviral activity against respiratory syncytial virus (RSV). The most potent one, cleistoperone A (1) with IC 50 value of 1.71 ± 0.61 μmol/L, could effectively inhibit virus replication via affecting the Akt/mTOR/p70S6K signaling pathway. The BBMN strategy led to the isolation of eighteen unprecedented cinnamoylphloroglucinol-terpene adducts from Cleistocalyx operculatus. Cleistoperone A (1) showed potent anti-RSV activity via affecting the Akt/mTOR/p70S6K signaling pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Amino acids with unusual types of chirality and their derivatives have recently attracted attention as precursors in the synthesis of chiral catalysts and peptide analogues with unique properties. In this study, we have synthesized a new nido-carborane-based planar-chiral amino acid, in the molecule of which the amino group is directly bonded to the B(3) atom, and the carboxyl group is attached to the B(9) atom through the CH2S+(Me) fragment. 3-Amino-9-dimethylsulfonio-nido-carborane, prepared in three steps from 3-amino-closo-carborane in a high yield, was a key intermediate in the synthesis of the target planar-chiral amino acid. The carboxymethyl group at the sulfur atom was introduced by the demethylation reaction of the dimethylsulfonio derivative, followed by S-alkylation. The structure of new 3,9-disubstituted nido-carboranes was studied for the first time using NMR spectroscopy. The resonances of all boron atoms in the 11B NMR spectrum of 3-amino-9-dimethylsulfonio-nido-carborane were assigned based on the 2D NMR correlation experiments. The nido-carborane-based planar-chiral amino acid and related compounds are of interest as a basis for peptide-like compounds and chiral ligands. [ABSTRACT FROM AUTHOR]

As a novel type of macrocycles with attractive planar chirality, pillar[5]arenes have gained increasing research interest over the past decades, enabling their widespread applications in diverse fields such as porous materials, molecular machines, and chiral luminescence materials. However, the catalytic methodology towards the enantioselective synthesis of planar chiral pillar[5]arenes remains elusive. Here we report a novel method for the enantioselective synthesis of planar chiral pillar[5]arenes via asymmetric Sonogashira coupling, giving access to a wide range of highly functionalized planar chiral pillar[5]arenes, including both homo‐ and hetero‐rimmed ones, with excellent enantioselectivities. Attractively, the resultant planar chiral pillar[5]arenes show great potential for widespread use in many areas such as chiral luminescent materials. This work not only enables the successful synthesis of planar chiral pillar[5]arenes with abundant structural and functional diversity as key building blocks for practical applications but also enriches the asymmetric cross‐coupling methodologies in organic synthetic chemistry. [ABSTRACT FROM AUTHOR]

Planar chirality, as one of the most important manifestations of chirality, is frequently employed to constrain three‐dimensional chiral configurations. Recent advancements in the study of planar chirality by chemists have opened up innovative possibilities for designing new catalysts, developing novel drugs, and creating new optical materials. However, the flexible ansa chains present a challenge during the synthesis process of these unique planar‐chiral macrocycles, hindering chemists from achieving high enantioselectivity. In this mini review, we primarily introduce the catalytic asymmetric synthesis methods that have been reported for late‐stage functionalization of planar macrocycles to generate planar chirality. Additionally, we present several recent examples of catalytic enantioselective synthesis of mechanically planar‐chiral rotaxanes through late‐stage functionalization methods. The sources of stereoselectivity are also discussed in this mini review. We aim to inform more researchers about this field and attract chemists to engage in this important and scientifically significant area of research. [ABSTRACT FROM AUTHOR]

BACKGROUND: Potato virus Y (PVY) is a prominent representative of plant viruses. It can inflict severe damage upon Solanaceae plants, leading to global dissemination and substantial economic losses. To discover new antiviral agents, a class of planar chiral thiourea molecules through the key step of N‐heterocyclic carbene‐catalyzed nitrile formation reaction was synthesized with excellent optical purities for antiviral evaluations against plant virus PVY. RESULTS: The absolute configurations of the planar chiral compounds exhibited obvious distinctions in the anti‐PVY activities. Notability, compound (S)‐4u exhibited remarkable curative activities against PVY, with a half maximal effective concentration (EC50) of 349.3 μg mL−1, which was lower than that of the ningnanmycin (NNM) (EC50 = 400.8 μg mL−1). Additionally, The EC50 value for the protective effects of (S)‐4u was 146.2 μg mL−1, which was superior to that of NNM (276.4 μg mL−1). Furthermore, the mechanism‐of‐action of enantiomers of planar chiral compound 4u was investigated through molecular docking, defensive enzyme activity tests and chlorophyll content tests. CONCLUSION: Biological mechanism studies have demonstrated that the configuration of planar chiral target compounds plays a crucial role in the molecular interaction with PVY‐CP, enhancing the activity of defense enzymes and affecting chlorophyll content. The current study has provided significant insights into the roles played by planar chiralities in plant protection against viruses. This paves the way for the development of novel green pesticides bearing planar chiralities with excellent optical purities. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Here, we successfully synthesized four structurally analogous, self‐assembled chiral molecular tubes with relatively high yields. This achievement involved the condensation of six equivalents of enantiomerically pure trans‐cyclohexane‐1,2‐diamine (trans‐CHDA) and three equivalents of the corresponding tetraformyl precursor. Each precursor was equipped with a luminescent linker terminated by two m‐phthalaldehyde units. Even though these tetraformyl precursors are barely soluble in almost all organic solvents, the molecular tubes are highly soluble in nonpolar solvents such as chloroform, allowing us to fully characterize them in solution. The stereo‐chirality of the chiral bisamino building blocks endows the frameworks of molecular tubes with planar chirality. As a consequence, all of these molecular tubes exhibit circularly polarized luminescence (CPL) with relatively large dissymmetry values |glum| up to 7×10−3, providing an efficient method for synthesizing CPL‐active materials. [ABSTRACT FROM AUTHOR]

Highly symmetrical and aesthetically pleasing molecules have attracted the attention of organic chemists. We synthesized new highly symmetric stereogenic π-conjugated macrocycles with planar or axial chirality. Macrocyclic oligomers synthesized by Yamamoto coupling or Suzuki–Miyaura cross-coupling from the π-unit containing chirality. These cyclization reactions gave multiple oligomers in relatively high yields. We then elucidated their structures and investigated their chiroptical properties, including circular dichroism (CD) and circularly polarized luminescence (CPL). Because of the selection rule for rigid and symmetric structures, these macrocycles exhibit a high dissymmetry factor (gabs or glum) for circularly polarized light in CD or CPL. Several rigid cyclic compounds retain a highly symmetric structure in the excited state and exhibit higher glum values than common chiral organic compounds. This Account provides a brief background regarding chiroptical properties, followed by a summary of the various macrocycles synthesized in this study. We are glad if this Account will be a source of ideas not only for chemists working with π-conjugated compounds, but also for synthetic chemists working with chiral compounds, especially those engaged in asymmetric synthesis. 1 Introduction 2 Brief Description of Chiroptical Properties 3 Stereogenic Macrocycle Based on [2.2]Paracyclophane 3.1 Stereogenic Double-decker Oligothiophene 3.2 Stereogenic Biselenophene Macrocycle 3.3 Helical Oligophenylene Linked with [2.2]Paracyclophane 4 Stereogenic Macrocycle Based on Binaphthyl 4.1 Cyclic Oligomer of Chiral Binaphthyl 4.2 Doubly Twisted Binaphthyl Dimer 4.3 Cyclic Oligomer of Binaphthyl Extended with Paraphenylene 4.4 Curved Helical Paraphenylene Anchoring Chiral Binaphthyl 4.5 Binaphthyl-Hinged [5]-Helicene 5 Summary [ABSTRACT FROM AUTHOR]

Since their discovery, [2.2]paracyclophane (pCp) and its derivatives have fascinated the scientific community due to their original molecular architecture and unusual electronic behavior. Over the years, significant efforts have been devoted to the development of substituted pCps for a variety of applications in different fields, ranging from organic synthesis and asymmetric catalysis to polymer chemistry and material science. This review describes a series of useful approaches that allow chemists to selectively decorate pCps, control the planar chirality that these molecules can display as soon as they are functionalized, and tune their photophysical behaviors. For each of these aspects of paracyclophane chemistry, selected examples of major advances are presented, and possible directions for future research are outlined. The application of pCp as central core for the development of uncommon 3D luminophores is finally highlighted. Emphasis is placed on the potential use of planar chiral luminescent paracyclophanes as antennas or ligands for the design of multifunctional lanthanide complexes, a quite underdeveloped but highly promising area for future research endeavors. [ABSTRACT FROM AUTHOR]

Colloidal crystal engineering with DNA allows one to design diverse superlattices with tunable lattice symmetry, composition, and spacing. Most of these structures follow the complementary contact model, maximizing DNA hybridization on building blocks and producing relatively close-packed lattices. Here, low-symmetry kagome superlattices are assembled from DNA-modified gold bipyramids that can engage only in partial DNA surface matching. The bipyramid dimensions and DNA length can be engineered for two different superlattices with rhombohedral unit cells, including one composed of a periodic stacking of kagome lattices. Enabled by the partial facet alignment, the kagome lattices exhibit lattice distortion, bipyramid twisting, and planar chirality. When conjugated with Cy-5 dyes, the kagome lattices serve as cavities with high-density optical states and large Purcell factors along lateral directions, leading to strong dipole radiation along the z axis and facet-dependent light emission. Such complex optical properties make these materials attractive for lasers, displays, and quantum sensing constructs. [ABSTRACT FROM AUTHOR]

Optical chirality sensing has gained significant attention in recent years. Within this field, the quest for stereodynamic chiroptical probes capable of detecting cryptochiral guests presents a formidable challenge. Macrocycles exhibiting planar chirality have emerged as promising candidates for amplifying the chirality of cryptochiral guests. In this study, we demonstrate that the formation of host‐guest complexes between cryptochiral molecules and planar chiral prismarenes triggers electronic circular dichroism (ECD) signals via host‐guest complexation‐induced chirality amplification. The absolute configuration of the most stable chiral macrocyclic host‐guest complex has been established by resorting to both exciton model and DFT computations. Furthermore, we demonstrated that this supramolecular chirality sensing system can be employed to determine the enantiomeric composition of scalemic mixtures by measuring the ECD bands intensity. The information described here opens the way for the use of prismarenes as stereodynamic probes for sensing of cryptochiral guests. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL), as an important chiroptical phenomenon, can not only directly characterize excited-state structural information about chiroptical materials but also has great application prospects in 3D optical displays, information storage, biological probes, CPL lasers and so forth. Recently, chiral organic small molecules with CPL have attracted a lot of research interest because of their excellent luminescence efficiency, clear molecular structures, unique flexibility and easy functionalization. Planar chiral organic compounds make up an important class of chiral organic small molecular materials and often have rigid macrocyclic skeletons, which have important research value in the field of chiral supramolecular chemistry (e.g., chiral self-assembly and chiral host–guest chemistry). Therefore, research into planar chiral organic compounds has become a hotspot for CPL. It is time to summarize the recent developments in CPL-active compounds based on planar chirality. In this feature article, we summarize various types of CPL-active compounds based on planar chirality. Meanwhile, we overview recent research in the field of planar chiral CPL-active compounds in terms of optoelectronic devices, asymmetric catalysis, and chiroptical sensing. Finally, we discuss their future research prospects in the field of CPL-active materials. We hope that this review will be helpful to research work related to planar chiral luminescent materials and promote the development of chiral macrocyclic chemistry. [ABSTRACT FROM AUTHOR]

Cylinder‐shaped macrocycles composed of π‐panels have attracted special attention as one of the best platforms for the development of organic molecule‐based chiroptical materials. Pillar[n]arenes are a class of macrocycles with the advantage of easy preparation but have not been extensively investigated from the perspective of luminescent molecules. However, common alkoxy pillar[n]arenes are fluorescent in non‐haloalkane solvents, showing potential to be used for molecule‐based chiroptical materials. In this work, circularly polarized luminescence (CPL) spectra are reported for a pillar[5]arene with stable planar chirality using tetrahydrofuran (THF) and cyclohexane as solvents, which has been missing for many years. The pillar[5]arene also forms co‐aggregates with 1,4‐bis(phenylethynyl)benzene and 1,4‐bis[(pentafluorophenyl)ethynyl]benzene in THF/H2O mixtures, owing to a hydrophobic effect. The co‐aggregates with the fluorinated π‐rod display a new low‐energy absorption peak and broad emission band as well as intense circular dichroism and CPL signals. Chiral information from the enantiopure pillar[5]arene core is efficiently transmitted to the co‐aggregates with the π‐conjugated rod, leading to the highest dissymmetry factor for CPL (2.9 × 10−2 at 472 nm) among pillar[n]arene‐based CPL materials. [ABSTRACT FROM AUTHOR]

Chirality constitutes an inherent attribute of nature. The catalytic asymmetric synthesis of molecules with central, axial, and helical chirality is a topic of intense interest and is becoming a mature field of research. However, due to the difficulty in synthesis and the lack of a prototype, less attention has been given to planar chirality arising from the destruction of symmetry on a single planar ring. Herein, we report the catalytic asymmetric synthesis of planar-chiral dianthranilides, a unique class of tub-shaped eight-membered cyclic dilactams. This protocol is enabled by cinchona alkaloid-catalyzed (dynamic) kinetic resolution. Under mild conditions, various C2- or C1-symmetric planar-chiral dianthranilides have been readily prepared in high yields with excellent enantioselectivity. These dianthranilides can serve as an addition to the family of planar-chiral molecules. Its synthetic value has been demonstrated by kinetic resolution of racemic amines via acyl transfer, enantiodivergent synthesis of the natural product eupolyphagin, and preliminary antitumor activity studies. Chirality has long fascinated chemists, but asymmetric synthesis has largely focused on central, axial, and helical chirality to date. Here, the authors synthesize dianthranilides with planar chirality, via cinchona alkaloid-catalyzed (dynamic) kinetic resolution. [ABSTRACT FROM AUTHOR]

A family of ferrocenyl amino alcohols (14 examples) has been prepared from the corresponding planar chiral ketones and evaluated as a new class of chiral ligands for asymmetric ethyl‐ and phenylzinc additions to aldehydes. The highly enantioselective synthesis of these ligands is facile, scalable, robust and relies on the use of cheaply available starting materials. Asymmetric ethyl additions proceeded smoothly at ambient temperature, with reaction times as short as 1 hour furnishing the desired products in up to 90 % yield and 99 % ee. The corresponding phenyl additions afforded products in up to 81 % yield and 88 % ee. The observed stereochemical outcome for the addition of diethylzinc was rationalized and the key proposed transition state was supported by an analysis of the X‐ray structures of a series of amino alcohol ligands. [ABSTRACT FROM AUTHOR]

A benzannulated double aza[9]helicene 1 was successfully synthesized via a one‐pot oxidative fusion reaction. 1 was derivatized to N‐alkylated double aza[9]helicene 1‐Et and 1‐Bu, whose structures were determined by X‐ray diffraction analysis. 1‐Et and 1‐Bu exhibited red‐shifted absorption and fluorescence spectra compared to single aza[9]helicene. The double aza[9]helicenes were expected to have two different conformers. Consistent with solid‐state structure, the chiral‐isomer was estimated to be more stable by 16 kcal/mol relative to meso‐isomer. Indeed, enantiomers of 1‐Et and 1‐Bu were optically resolved by HPLC and showed mirror‐imaged CD and CPL spectra with the CPL brightness up to 19.2 M−1cm−1 for 1‐Bu. [ABSTRACT FROM AUTHOR]

Kinetic resolution of 4‐(2‐nitrovinyl)[2.2]paracyclophane based on N‐terminal–guanidinylated resin–bound helical peptide catalyzed asymmetric Michael addition of malonate esters was developed. This approach provides a new pathway to enantiopure paracyclophane derivatives characterized by both planar and central chirality, along with the recovery of the chiral substrate with a selectivity factor of up to 111. Additionally, the synthetic potential of the resulting products has been showcased through their successful transformation into derivatives of β‐substituted γ‐aminobutyric acid. [ABSTRACT FROM AUTHOR]

How Nature synthesizes enantiomerically pure substances from achiral or racemic resources remains a mystery. In this study, we aimed to emulate this natural phenomenon by constructing chiral tetrahedral cages through self‐assembly, achieved by condensing two achiral compounds–a trisamine and a trisaldehyde. The occurrence of intercomponent CH⋅⋅⋅π interactions among the phenyl building blocks within the cage frameworks results in twisted conformations, imparting planar chirality to the tetrahedrons. In instances where the trisaldehyde precursor features electron‐withdrawing ester side chains, we observed that the intermolecular CH⋅⋅⋅π forces are strong enough to prevent racemization. To attain enantioselective self‐assembly, a chiral amine was introduced during the imine formation process. The addition of three equivalents of chiral amino mediator to one equivalent of the achiral trisaldehyde precursor formed a trisimino intermediate. This chiral compound was subsequently combined with the achiral trisamino precursor, leading to an imine exchange reaction that releasing the chiral amino mediator and formation of the tetrahedral cage with an enantiomeric excess (ee) of up to 75 %, exclusively composed of achiral building blocks. This experimental observation aligns with theoretical calculations based on the free energies of related cage structures. Moreover, since the chiral amine was not consumed during the imine exchange cycle, it enabled the enantioselective self‐assembly of the tetrahedral cage for multiple cycles when new batches of the achiral trisaldehyde and trisamino precursors were successively added. [ABSTRACT FROM AUTHOR]

Five diastereomers of ruthenium(II) complexes based on quinolinophaneoxazoline ligands were investigated by vibrational circular dichroism (VCD) in the mid‐IR and CH stretching regions. Diastereomers differ in three sources of chirality: the planar chirality of the quinolinophane moiety, the central chirality of an asymmetric carbon atom of the oxazoline ring, and the chirality of the ruthenium atom. VCD, allied to DFT calculations, has been found to be effective in disentangling the various forms of chirality. In particular, a VCD band is identified in the CH stretching region directly connected to the chirality of the metal. The analysis of the calculated VCD spectra is carried out by partitioning the complexes into fragments. The anharmonic analysis is also performed with a recently proposed reduced‐dimensionality approach: such treatment is particularly important when examining spectroscopic regions highly perturbed by resonances, like the CH stretching region. [ABSTRACT FROM AUTHOR]

Since the discovery of classical chiral oxazoline ferrocene ligands in 1995, they have become pivotal in transition metal-catalyzed asymmetric transformations. Over the past decade, a notable evolution has been observed with the emergence of siloxane-substituted oxazoline ferrocenes, demonstrating significant potential as chiral ligands and catalysts. These compounds have consistently delivered exceptional results in diverse and mechanistically distinct transformations, surpassing the capabilities of classical oxazoline ferrocene ligands. This review meticulously delineates the research progress on siloxane-substituted oxazoline ferrocene compounds. It encompasses the synthesis of crucial precursors and desired products, highlights their achievements in asymmetric catalysis reactions, and delves into the exploration of the derivatization of these compounds, emphasizing the introduction of ionophilic groups and their impact on the recovery of transition metal catalysts. In addition to presenting the current state of knowledge, this review propels future research directions by identifying potential topics for further investigation concerning the siloxane-tagged derivatives. These derivatives are poised to be promising candidates for the next generation of highly efficient ligands and catalysts. [ABSTRACT FROM AUTHOR]

Electropolymerization is a convenient way to obtain conducting polymers (CPs) directly adhered to an electrode surface. CPs are well-known for their various application fields in photovoltaic cells, chemical sensors, and electronics. By implementing chirality into a CP, the application possibilities will spread further onto chiral sensors or optoelectronics. In this work, we introduce a new inherently chiral polymer based on a macrocyclic 3,4-ethylenedioxythiophene-diketopyrrolopyrrole-3,4-ethylenedioxythiophene triad (EDOT-DPP-EDOT) fused by 1,4-phenylene groups, which was prepared via oxidative electropolymerization directly on the electrode surface. The investigation of the chiroptical properties was performed by circular dichroism spectroscopy in the solid state. The enantiomeric pure polymer films obtained showed dissymmetry factors of up to −2.71 × 10−4, whereby linear dichroism contributions can be widely excluded.

Amino acids with unusual types of chirality and their derivatives have recently attracted attention as precursors in the synthesis of chiral catalysts and peptide analogues with unique properties. In this study, we have synthesized a new nido-carborane-based planar-chiral amino acid, in the molecule of which the amino group is directly bonded to the B(3) atom, and the carboxyl group is attached to the B(9) atom through the CH2S+(Me) fragment. 3-Amino-9-dimethylsulfonio-nido-carborane, prepared in three steps from 3-amino-closo-carborane in a high yield, was a key intermediate in the synthesis of the target planar-chiral amino acid. The carboxymethyl group at the sulfur atom was introduced by the demethylation reaction of the dimethylsulfonio derivative, followed by S-alkylation. The structure of new 3,9-disubstituted nido-carboranes was studied for the first time using NMR spectroscopy. The resonances of all boron atoms in the 11B NMR spectrum of 3-amino-9-dimethylsulfonio-nido-carborane were assigned based on the 2D NMR correlation experiments. The nido-carborane-based planar-chiral amino acid and related compounds are of interest as a basis for peptide-like compounds and chiral ligands.

Two ferrocene derivatives, namely, 1,2-(tetramethylene)-ferrocene and 1,2,1′,2′-bis(tetramethylene)-ferrocene, were synthesized in a four-step reaction sequence starting from ferrocene. Friedel–Crafts acylation of ferrocene using succinic anhydride gave mono- or bis(3-carboxypropinoyl)-ferrocene depending on the stoichiometry of succinic anhydride. The reduction of the keto groups to methylene followed by ring-closing using trifluoroacetic anhydride gave 1,2-(α-ketotetramethylene)-ferrocene or 1,2,1′,2′-bis(α-ketotetramethylene)-ferrocene. The diastereomeric mixture of the latter diketones was separated using column chromatography, characterized via single-crystal X-ray analysis, and assigned its stereochemistry. Reduction of the keto groups to methylene under Clemmensen conditions gave homoannular mono- or bis(tetramethylene)-ferrocene derivatives. The molecular structure of 1,2-(tetramethylene)-ferrocene revealed that the ipso carbon atoms of the cyclopentadienyl group are 0.023(3) Å farther away from Fe(II) compared to the remaining three carbon atoms. Both complexes exhibit lower half-wave oxidation potentials than ferrocene, possibly due to the electron-releasing effects of the tetramethylene bridges. [ABSTRACT FROM AUTHOR]

This article provides an overview of the synthesis and applications of planar chiral ferrocene derivatives. It discusses two main approaches to introducing planar chirality in ferrocene compounds: base-mediated ortho-metallation and transition-metal-catalyzed C-H bond activations. These methods allow for the introduction of various functional groups and have applications in asymmetric catalysis, medicinal chemistry, and materials science. The authors, Tomáš Čarný and Radovan Šebesta, are experts in organic chemistry and have conducted research in the field of ferrocene derivatives. [Extracted from the article]

The reaction of trans‐[Pt(DMSO)2MeCl] with 2‐alkylsubstituted pyridines pyR affords a series of complexes of the type [Pt(pyR)(DMSO)MeCl]. These complexes are rare examples of organometallic square‐planar complexes having four different ligands. Of the three possible geometric isomers, only the trans(N,S)‐[Pt(pyR)(DMSO)MeCl] was observed in solution and isolated in the solid state. However, the lack of chirality typical to square planar geometry can be resolved in several ways one of which is described in this paper. 1H NMR studies reveal diastereotopicity of the DMSO methyls, as well as the CH2 protons in the ethyl‐ and neopentyl‐pyridine complexes and the methyls in the isopropyl‐pyridine derivative. This observation can be ascribed to restricted rotations around the Pt−N bond, thus resulting in the presence of planar chirality for these complexes. Additionally, large downfield shifts in the 1H NMR spectra of the α C−H protons in the pyridine substituents suggested the presence of Pt⋯H−C interactions, confirmed via single crystal X‐ray studies in the case of the isopropyl complex [Pt(pyip)(DMSO)MeCl] (4), which shows an apical Pt⋯H interaction with a short 2.585 Å distance. DFT calculations shed light into the stability of these complexes and the influence of the pyridine‐substituent on their chiral configuration. [ABSTRACT FROM AUTHOR]

Indole‐based planar‐chiral macrocycles are widely found in natural products and bioactive molecules. However, in sharp contrast to the preparation of indole‐based axially chiral structures, the enantioselective catalysis of indole‐based planar‐chiral macrocycles is still a formidable task so far. Here we report an N‐heterocyclic carbene (NHC)‐catalyzed intramolecular atroposelective macrocyclization of 3‐carboxaldehyde indole/pyrroles, featuring with broad substrate scope and good functional group tolerance, and allowing for a rapid access to diverse indole/pyrrole‐based planar‐chiral macrocycles with various tether‐lengths (10–16 members) in good yields and with excellent enantioselectivities. Importantly, the indole‐based macrocyclic structures with both planar and axial chirality were directly and efficiently obtained through this protocol with excellent enantioselectivities and diastereoselectivities. In addition, these synthesized planar‐chiral macrocycles offer many possibilities for chemists to develop new catalysts or ligands, as well as new reactions. [ABSTRACT FROM AUTHOR]

With the rapid development of asymmetric catalysis, the demand for the enantioselective synthesis of complex and diverse molecules with different chiral elements is increasing. Owing to the unique features of atropisomerism, the catalytic asymmetric synthesis of atropisomers has attracted a considerable interest from the chemical science community. In particular, introducing additional chiral elements, such as carbon centered chirality, heteroatomic chirality, planar chirality, and helical chirality, into atropisomers provides an opportunity to incorporate new properties into axially chiral compounds, thus expanding the potential applications of atropisomers. Thus, it is important to perform catalytic asymmetric transformations to synthesize atropisomers bearing multiple chiral elements. In spite of challenges in such transformations, in recent years, chemists have devised powerful strategies under asymmetric organocatalysis or metal catalysis, synthesizing a wide range of enantioenriched atropisomers bearing multiple chiral elements. Therefore, the catalytic asymmetric synthesis of atropisomers bearing multiple chiral elements has become an emerging field. This review summarizes the rapid progress in this field and indicates challenges, thereby promoting this field to a new horizon. [ABSTRACT FROM AUTHOR]

Supramolecular polymers based on chiral macrocycles have attracted increasing attention in the field of circularly polarized luminescence (CPL) owing to their unique properties. However, the construction of macrocyclic supramolecular polymers with highly efficient CPL properties in aggregate states still remains challenging. Herein, w e constructed a class of macrocycle‐based coordination polymers by combining the planar chiral properties of pillar[5]arene with the excellent fluorescence properties of aggregation‐induced emission luminogens. The formation of polymers enhances both the fluorescence and chiral properties, resulting in chiral supramolecular polymers with remarkable CPL properties. Increasing the aggregation degree of the polymers can further improve their CPL properties, as evidenced by a 21‐fold increase in the dissymmetry factor and an over 25‐fold increase in the fluorescence quantum yield in the aggregate state compared to the solution state. Such a synergistic effect of polymerization‐ and aggregation‐enhanced CPL can be explained by the restriction of intramolecular motions and aggregation‐induced conformation confinement. This work provides a promising method for developing highly efficient CPL supramolecular polymers. [ABSTRACT FROM AUTHOR]

Alkene planar chirality is introduced in the 'privileged' P-alkene phosphoramidite ligand 1. The resulting diastereomeric ligands (pR,R)-5 and (pS,R)-5 form optically pure complexes of Rh(I) and Pd(II), which catalyze conjugate additions of boron C-nucleophiles to enones and allylic alkylations, respectively. In the Rh-catalyzed reaction, the planar chirality of the alkene exerts absolute enantiocontrol over the potent BINOL auxiliary. [ABSTRACT FROM AUTHOR]

Abstract Supramolecular polymers based on chiral macrocycles have attracted increasing attention in the field of circularly polarized luminescence (CPL) owing to their unique properties. However, the construction of macrocyclic supramolecular polymers with highly efficient CPL properties in aggregate states still remains challenging. Herein, w e constructed a class of macrocycle‐based coordination polymers by combining the planar chiral properties of pillar[5]arene with the excellent fluorescence properties of aggregation‐induced emission luminogens. The formation of polymers enhances both the fluorescence and chiral properties, resulting in chiral supramolecular polymers with remarkable CPL properties. Increasing the aggregation degree of the polymers can further improve their CPL properties, as evidenced by a 21‐fold increase in the dissymmetry factor and an over 25‐fold increase in the fluorescence quantum yield in the aggregate state compared to the solution state. Such a synergistic effect of polymerization‐ and aggregation‐enhanced CPL can be explained by the restriction of intramolecular motions and aggregation‐induced conformation confinement. This work provides a promising method for developing highly efficient CPL supramolecular polymers.

Pillar[n]arenes are symmetrical macrocyclic compounds composed of benzene panels with para‐methylene linkages. Each panel usually exhibits planar chirality and prefers chirality‐aligned states. Because of this feature, pillar[n]arenes are attractive scaffolds for chiroptical materials that are easy to prepare and optically resolve and show intense circular dichroism (CD) signals. In addition, rotation of the panels endows the chirality of pillar[n]arenes with a dynamic nature. The chirality in tubular oligomers and supramolecular assemblies sometimes show time‐ and procedure‐dependent alignment phenomena. Furthermore, the CD signals of some pillar[n]arenes respond to the addition of chiral guests when their dynamic chirality is coupled with host–guest properties. By using diastereomeric pillar[n]arenes with additional chiral structures, the response can also be caused by achiral guests and changes of the environment, providing molecular sensors. [ABSTRACT FROM AUTHOR]

Studies on various macrocyclic arenes have received increasing attention due to their straightforward syntheses, convenient derivatization, and unique complexation properties. Represented by pillar[n]arenes, several distinctive macrocyclic arenes have recently emerged with the following characteristics: they possess a pair of enantiomeric planar chiral conformations, and interconversion between these enantiomeric conformations can be achieved through the flipping of ring units. Complexation of a chiral guest with these macrocyclic arenes will lead to a shift of the equilibrium between the Rp and Sp conformers, leading to intriguing possibilities for chiral induction and sensing. By the introduction of bulky substituents on the rims, employing rotaxanation or pseudocatenation, planar chirality could be locked, enabling the enantiomeric separation of the chiral structures. The induced or separated chiral conformers/compounds exhibit significant chiroptical properties. These macrocyclic arenes, with flipping-induced inversion of planar chirality, demonstrated intriguing chiral induction dynamics and kinetics. In this featured review, we systematically summarize the progress in chiroptical induction/regulation of these macrocyclic arenes, particularly in the fields of chiral sensing, molecular machines, molecular recognition, and assembly. [ABSTRACT FROM AUTHOR]