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A family of chiral perylene diimides (PDIs) was newly developed as excellent circularly polarized luminescence (CPL) materials. They are asymmetrically derivatized with a double‐alkyl‐chained L‐ or D‐glutamate unit and a linear or branched alkyl chain. When water is added to the tetrahydrofuran (THF) solution of glutamate‐PDI‐linear‐alkyl chain compounds, kinetically formed H‐aggregates are formed in globular nanoparticles (NPs). These NPs undergo spontaneous transformation into thermodynamically stable nanotubes via helical nanostructures, which showed structured broad spectra originating from the strong coupling of delocalized Frenkel excitations (FE) and charge transfer excitations (CTE). Significant enhancement of circular dichroism (CD), fluorescence quantum yield, and circularly polarized luminescence (CPL) with luminescence dissymmetry factor (glum) are observed during the transformation of NPs to the FE/CTE‐coupled helical and tubular structures. This transformation process is significantly accelerated by applying physical stimuli, i.e. ultrasonication or adding helical aggregates as seed crystals, a feature unique to living supramolecular polymerization. Meanwhile, the branched chain‐containing PDIs only form H‐aggregates and did not show FE/CTE hybrid exciton states with living supramolecular polymerization properties. This study unveils that suitably designed chiral PDI derivatives show FE/CTE coupling accompanied by high fluorescence quantum yields, enhanced chiroptical properties, and supramolecular living polymerization characteristics. [ABSTRACT FROM AUTHOR]

Two new structural motifs within the class of heteroleptic PdnAnBn assemblies, namely syn‐cis‐Pd3A3B3 bowls and bowl‐ (syn) or saddle‐ (anti) shaped cis‐Pd4A4B4 rings are introduced. All of the ten examples share a common longer fluorenone‐based bis‐monodentate ligand, equipped with meta‐pyridine donor groups. The ring size (3‐ vs. 4‐membered) and conformational preference (bowl vs. saddle) are controlled by the choice of the shorter ligand. These carry para‐pyridine donors, different aromatic backbones (benzene, thiophene or selenophene) and either no or small or bulky endohedral substituents, serving to control the nuclearity of the heteroleptic rings through different effects (ligand angle, charge distribution or backbone bulk). Moreover, the luminescence of the fluorenone ligand is conserved in the formed architectures. Emission intensity as well as host–guest properties vary depending on the inward‐pointing functions. All Pd3A3B3 assemblies are shown to bind chiral guest BINOL bis‐sulfonate which imparts its chirality to the entire host–guest complex. This results in a guest‐induced circular dichroism (CD) and circularly polarized luminescence (CPL) with dissymmetry factor glum up to 10−3. [ABSTRACT FROM AUTHOR]

Inherently chiral calix[4]arenes represent a unique type of chiral molecules with significant applications, yet their catalytic enantioselective synthesis remains largely underexplored. We report herein the catalytic enantioselective synthesis of inherently chiral calix[4]arenes through the sequential organocatalyzed enantioselective Povarov reaction and aromatizations. The chiral phosphoric acid catalyzed three‐component Povarov reaction involving amino group‐substituted calix[4]arenes, aldehydes and (di)enamides desymmetrized the prochiral calix[4]arene substrates, which was followed by various aromatization methods, resulting in a diverse array of novel quinoline‐containing calix[4]arenes with good yields and high enantioselectivities (up to 75 % yield, 99 % ee). The large‐scale enantioselective synthesis and diverse derivatizations of the chiral calix[4]arene products highlight the value of this method. Furthermore, preliminary exploration into their photophysical and chiroptical properties demonstrate the potential applications of these novel calix[4]arene molecules. [ABSTRACT FROM AUTHOR]

Cu‐catalyzed asymmetric allylic borylation of 3,3'‐disubstituted 1‐vinylcyclobutan‐1‐ols renders axially chiral allylborane systems, with high asymmetric induction for both enantiomers, by precise selection of the cis or trans substrate. The enantioenriched alkylidenecyclobutanes served as chiral platform to prove the conceptually challenging transference of the axial‐to‐point chirality through two new stereocenters and one pseudoasymmetric carbon generated via diastereoconvergent allylation of aldehydes, without enantioselective erosion. [ABSTRACT FROM AUTHOR]

Macrocycle‐based host–guest complexation offers an intriguing protocol in producing chiroptical materials, while the bulky size and dynamic exchange between hosts and guests hinders the ordered aggregation to afford the long‐range chiral arrangement. It remains great challenges in assembling cucurbit[n]urils (CB[n]s) included complexes to induce supramolecular chirality ascribed to the excellent water solubility and flexible packing. Herein, we unveiled the structural basis on the formation of chiroptical coassemblies from CB[n] (n=6, 7) complexes. Perylene diimides (PDIs) with cationic chiral pendants formed complexes in the aqueous media, which selectively showed chiroptical properties. Chlorination at the bay position, increasing alkyl length of cationic chiral pendants or reducing the number of polyaromatic rings would hinder the chiral aggregation. In a comprehensive manner, CB[6] favors ordered aggregation into one‐dimensional fibrous nanoarchitectures that greatly facilitates the supramolecular chirality. In contrast, CB[7] with larger cavity and water solubility shrinks the ordered arrangement of complexes, reducing the formation possibility of supramolecular chiral nanoarchitectures. This work suggests the great potential of CB[6] in the preparation and manipulation of supramolecular chiral assemblies, shedding light on the macrocycle‐based functional chiroptical materials. [ABSTRACT FROM AUTHOR]

Heteroatom‐embedded helical nanographenes (NGs) constitute an important and appealing class of intrinsically chiral materials. In this work, a series of B,N‐embedded helical NGs (BN‐HNGs) bearing azepines was synthesized via stepwise regioselective cyclodehydrogenation. First, the phenyl‐ or nitrogen‐bridged dimers were efficiently clipped into highly congested model compounds 1 and 2. Later, the controllable Scholl reactions of the tetraphenyl‐tethered precursor generated 1, 7 or 8 new C−C bonds, thereby establishing a robust method for the preparation of nonalternant BN‐HNGs with up to 31 fused rings. The helical bilayer nature was unambiguously verified by X‐ray diffraction analysis. The helical chirality was transferred to the stereogenic boron centers upon fluoride coordination, with a concave‐concave structure to comply with the bilayer skeleton. Notably, the largest nonalternant BN‐HNG (6) spontaneously resolved into a homochiral 41 helix structure as a molecular spiral staircase during crystallization via conglomerate formation at the single‐crystal scale. The large twisted C2‐symmetric π‐surface and the dynamic chiral skeleton induced by curved azepines might have synergistic effects on self‐recognition of enantiomers of 6 to achieve the intriguing spontaneous resolution behavior. The chiroptical properties of the enantiomer of 6 were further investigated, revealing that 6 had a strong chiroptical response in the visible range (400–700 nm). [ABSTRACT FROM AUTHOR]

Functionalization of quantum dots (QDs) and quantum rods (QRs) with ligands is essential for their further practical application across various domains. Dehydration‐assisted functionalization (DAF) is a versatile method applicable to a wide range of hydrophilic ligands with an affinity to the surface of QDs and QRs. This approach facilitates rapid one‐pot ligand exchange and dense modification by efficiently transferring these ligands onto the surface of QDs and QRs. This study demonstrates the efficacy of DAF in preparing chiral QRs, engineering the surface charge of QDs, utilizing QR aggregates, and conjugating dense DNA onto cadmium‐free InP/ZnS QDs. DAF therefore offers a versatile solution for hydrophilic ligand functionalization of QDs and QRs applicable to diverse applications. [ABSTRACT FROM AUTHOR]

Chirality in inorganic nanostructures has recently stimulated the attention of many researchers, both to unravel fundamental questions on the origin of chirality in inorganic and hybrid materials, as well as to introduce novel promising properties that are originated by the symmetry breaking. MoS2 is one of the most investigated among the large family of layered transition metal dichalcogenides. In particular, the metastable metallic 1T−MoS2 phase is of large interest for potential applications. However, due to thermodynamic reasons, the synthesis of 1T−MoS2 phase is quite challenging. Herein, we present the first synthesis of chiral 1T−MoS2 phase which shows remarkably high chiroptical activity with a g‐factor up to 0.01. Chiral 1T−MoS2 was produced using tartaric acid as a chiral ligand to induce symmetry breaking during the material's growth under hydrothermal conditions, leading to the formation of distorted hierarchical nanosheet assemblies exhibiting chiral morphology. Thorough optimization of the synthetic conditions was carried out to maximize chiroptical activity, which is strongly related to the nanostructures' morphology. Finally, the formation mechanism of the chiral 1T−MoS2 nanosheet assemblies was investigated, focusing on the role of molecular intermediates in the growth of the nanosheets and the transfer of chirality. [ABSTRACT FROM AUTHOR]

A stimuli‐responsive multiple chirality switching material, which can regulate opposed chiral absorption characteristics, has great application value in the fields of optical modulation, information storage and encryption, etc. However, due to the rareness of effective functional systems and the complexity of material structures, developing this type of material remains an insurmountable challenge. Herein, a smart polymer film with multiple chirality inversion properties was fabricated efficiently based on a newly‐designed acid & base‐sensitive dye‐grafted helical polymer. Benefited from the cooperative effects of various weak interactions (hydrogen bonds, electrostatic interaction, etc.) under the aggregated state, this polymer film exhibited a promising acid & base‐driven multiple chirality inversion property containing record switchable chiral states (up to five while the solution showed three‐state switching) and good reversibility. The creative exploration of such a multiple chirality switching material can not only promote the application progress of current chiroptical regulation technology, but also provide a significant guidance for the design and synthesis of future smart chiroptical switching materials and devices. [ABSTRACT FROM AUTHOR]

Mechanically interlocked molecules (MIMs) are promising platforms for developing functionalized artificial molecular machines. The construction of chiral MIMs with appealing circularly polarized luminescence (CPL) properties has boosted their potential application in biomedicine and the optical industry. However, there is currently little knowledge about the CPL emission mechanism or the emission dynamics of these related MIMs. Herein, we demonstrate that time‐resolved circularly polarized luminescence (TRCPL) spectroscopy combined with transient absorption (TA) spectroscopy offers a feasible approach to elucidate the origins of CPL emission in pyrene‐functionalized topologically chiral [2]catenane as well as in a series of pyrene‐functionalized chiral molecules. For the first time, direct evidence differentiating the chiroptical signals originating from either topological (local state emission) or Euclidean chirality (excimer state emission) in these pyrene‐functionalized chiral molecules has been discovered. Our work not only establishes a novel and ideal approach to study CPL mechanism, but also provides a theoretical foundation for the rational design of novel chiral materials in the future. [ABSTRACT FROM AUTHOR]

A series of metal–organic cages featuring two stereogenic elements, in terms of the twisting of amide moieties within the ligand backbones and the rotation of diazaanthracene segments along the ligand ridges, were exploited. These two chiral components are correlative and serve as relays for transmitting chirality information between the internal and external cages. The chirality information induced by a chiral guest inside the cage cavity can pass through the cage framework and influence the orientation of the diazaanthracene segments on the periphery of the cage. In turn, the chirality of a stereogenic center within the diazaanthracene segments can transfer back into the cavity, enabling discrimination of enantiomeric guests. [ABSTRACT FROM AUTHOR]

Chiral organic molecules offer a promising platform for exploring circularly polarized lasing, which, however, faces a great challenge that the spatial separation of molecular chiral and luminescent centers limits chiroptical activity. Here we develop a helically chiral supramolecular system with completely overlapped chiral and luminescent units for realizing high‐performance circularly polarized lasing. Adaptive helical chirality is obtained by incorporating chiral agents into organic microcrystals. Benefiting from the efficient coupling of stimulated emission with the adaptive helical chirality, the supramolecular microcrystals enable high‐performance circularly polarized lasing emission with dissymmetry factors up to ~0.7. This work opens up the way to rational design of chiral organic materials for circularly polarized lasing. [ABSTRACT FROM AUTHOR]

To explore the chirality induction and switching of topological chirality, poly[2]catenanes composed of helical poly(phenylacetylenes) (PPAs) main chain and topologically chiral [2]catenane pendants are described for the first time. These poly[2]catenanes with optically active [2]catenanes on side chains were synthesized by polymerization of enantiomerically pure topologically chiral [2]catenanes with ethynyl polymerization site and/or point chiral moiety. The chirality information of [2]catenane pendants was successfully transferred to the main chain of polyene backbones, leading to preferred‐handed helical conformations, while the introduction of point chiral units has negligible effect on the overall helices. More interestingly, attributed to unique dynamic feature of the [2]catenane pendants, these polymers revealed dynamic response behaviors to solvents, temperature, and sodium ions, resulting in the fully reversible switching on/off of the chirality induction. This work provides not only new design strategy for novel chiroptical switches with topologically chiral molecules but also novel platforms for the development of smart chiral materials. [ABSTRACT FROM AUTHOR]

Nature uses various chiral and unsymmetric building blocks to form substantial and complex supramolecular assemblies. In contrast, the majority of organic ligands used in metallosupramolecular chemistry are symmetric and achiral. Here we extend the group of unsymmetric chiral bile acids used as a scaffold for organic bispyridyl ligands by employing chenodeoxycholic acid (CDCA), an epimer of the previously used ursodeoxycholic acid (UDCA). The epimerism, flexibility, and bulkiness of the ligands leads to large structural differences in coordination products upon reaction with Pd(NO3)2. The UDCA‐bispyridyl ligand self‐assembles quantitatively into a single crown‐like Pd3L6 complex, whereas the CDCA ligand provides a mixture of coordination complexes of general formula PdnL2n, i.e., Pd2L4, Pd3L6, Pd4L8, Pd5L10, and even Pd6L12 containing an impressive 120 chiral centers. The coordination products were studied by a combination of analytical methods, with ion‐mobility mass spectrometry (IM‐MS) providing valuable details on their structure and allowed an effective separation of m/z 1461 to individual signals according to the arrival time distribution, thereby revealing four different ions of [Pd3L6(NO3)3]3+, [Pd4L8(NO3)4]4+, [Pd5L10(NO3)5]5+, and [Pd6L12(NO3)6]6+. The structures of all the complexes were modelled using DFT calculations. Finally, the challenges and conclusions in determining the specific structural identity of these unsymmetric species are discussed. [ABSTRACT FROM AUTHOR]

The self‐assembly behavior of a heptanediamide derivative that contains a four‐ring fused π‐skeleton on its central methylene carbon atom has been examined. This molecule, which also contains two octyl chains, gelated the nonpolar solvent methylcyclohexane through the formation of fibrous nanostructures with hydrogen‐bonding networks through a cooperative nucleation–elongation process. The supramolecular polymerization is accompanied by bathochromic shifts of both the absorption and fluorescence bands while maintaining a fluorescence quantum yield comparable to that of the monomeric state. Theoretical calculations provided an energetically stable structure, in which the π‐skeletons are stacked with an offset of more than 8.0 Å, replicating the experimentally observed absorption change due to exciton coupling. Moreover, a slow transition with an inversion of the chiral arrangement of the π‐conjugated moieties was induced by replacing the octyl chains with chiral alkyl chains. Our molecular‐design strategy was further applied to a five‐ring fused π‐skeleton, which also forms an offset π‐stacking arrangement and exhibits more effective chiral exciton coupling in the aggregated state. [ABSTRACT FROM AUTHOR]

The mature synthetic methodologies enable us to rationally design and produce chiral nanographenes (NGs), most of which consist of multiple helical motifs. However, inherent chirality originating from twisted geometry has just emerged to be employed in chiral NGs. Herein, we report a red‐emissive chiral NG constituted of orthogonally arranged two‐fold twisted π‐skeletons at a contorted pyrene core which contributes to optical transitions of S0→S1 and vice versa. The thus‐obtained NG exhibited a robustness on its redox properties through 2e− uptake/release. The chemical oxidation generated stable radical cation whose absorption covers near‐infrared I and II regions. Overall, the contorted pyrene core governs electronic nature of the chiral NG. The twist operation on NGs would be, therefore, a design strategy to alter conventional chirality induction on NGs. [ABSTRACT FROM AUTHOR]

Large dissymmetry factor of the circularly polarized luminescence (gCPL) was observed in ligand and coordination tuned chiral tetrakis europium (Eu(III)) complexes with ammonium cations. The gCPL value was estimated to be −1.54, which is the largest among chiral luminescent molecules. Through photophysical measurements, single crystal X‐ray structural analyses and quantum chemical calculations, changes in the geometric and electronic structures were observed for a series of chiral tetrakis Eu(III) complexes which enhanced the gCPL value. The emission quantum yield and photosensitized energy transfer efficiencies of chiral Eu(III) complexes with ammonium cations were also larger than those of chiral Eu(III) complex with Cs+. Based on the systematic modifications and analyses for chiral tetrakis Eu(III) complex, effect of the ammonium cation on enhanced CPL brightness is reported. [ABSTRACT FROM AUTHOR]

We report a series of coordination cages that incorporate peptide chains at their vertices, prepared through subcomponent self‐assembly. Three distinct heterochiral tripeptide subcomponents were incorporated, each exhibiting an L−D−L stereoconfiguration. Through this approach, we prepared and characterized three tetrahedral metal‐peptide cages that incorporate thiol and methylthio groups. The gelation of these cages was probed through the binding of additional metal ions, with the metal‐peptide cages acting as junctions, owing to the presence of sulfur atoms on the peripheral peptides. Gels were obtained with cages bearing cysteine at the C‐terminus. Our strategy for developing functional metal‐coordinated supramolecular gels with a modular design may result in the development of materials useful for chemical separations or drug delivery. [ABSTRACT FROM AUTHOR]

We present the inaugural synthesis of a chiral teropyrene achieved through a four‐fold alkyne benzannulation catalyzed by InCl3, resulting in good yields. The product underwent thorough characterization using FT‐Raman and FT‐IR spectroscopies, demonstrating a close agreement with calculated spectra. X‐ray crystallographic analysis unveiled a notable twist in the molecule's backbone, with an end‐to‐end twist angle of 51°, consistent with computational predictions. Experimentally determined enantiomeric inversion barriers revealed a significant energy barrier of 23 kcal/mol, facilitating the isolation of enantiomers for analysis by circular dichroism (CD) and circularly polarized luminescence (CPL) spectroscopies. These findings mark significant strides in the synthesis and characterization of chiral teropyrenes, offering insights into their structural and spectroscopic properties. [ABSTRACT FROM AUTHOR]

Organic materials with switchable dual circularly polarized luminescence (CPL) are highly desired because they can not only directly radiate tunable circularly polarized light themselves but also induce CPL for guests by providing a chiral environment in self‐assembled structures or serving as the hosts for energy transfer systems. However, most organic molecules only exhibit single CPL and it remains challenging to develop organic molecules with dual CPL. Herein, novel through‐space conjugated chiral foldamers are constructed by attaching two biphenyl arms to the 9,10‐positions of phenanthrene, and switchable dual CPL with opposite signs at different emission wavelengths are successfully realized in the foldamers containing high‐polarizability substitutes (cyano, methylthiol and methylsulfonyl). The combined experimental and computational results demonstrate that the intramolecular through‐space conjugation has significant contributions to stabilizing the folded conformations. Upon photoexcitation in high‐polar solvents, strong interactions between the biphenyl arms substituted with cyano, methylthio or methylsulfonyl and the polar environment induce conformation transformation for the foldamers, resulting in two transformable secondary structures of opposite chirality, accounting for the dual CPL with opposite signs. These findings highlight the important influence of the secondary structures on the chiroptical property of the foldamers and pave a new avenue towards efficient and tunable dual CPL materials. [ABSTRACT FROM AUTHOR]

Chiral multi‐resonance thermally activated delayed fluorescence (CP‐MR‐TADF) materials hold promise for circularly polarized organic light‐emitting diodes (CP‐OLEDs) and 3D displays. Herein, we present two pairs of tetraborated intrinsically axial CP‐MR‐TADF materials, R/S‐BDBF‐BOH and R/S‐BDBT‐BOH, with conjugation‐extended bidibenzo[b,d]furan and bidibenzo[b,d]thiophene as chiral sources, which effectively participate in the distribution of the frontier molecular orbitals. Due to the heavy‐atom effect, sulfur atoms are introduced to accelerate the reverse intersystem crossing process and increase the efficiency of molecules. R/S‐BDBF‐BOH and R/S‐BDBT‐BOH manifest ultra‐pure blue emission with a maximum at 458/459 nm with a full width at half maximum of 27 nm, photoluminescence quantum yields of 90 %/91 %, and dissymmetry factors (|gPL|) of 6.8×10−4/8.5×10−4, respectively. Correspondingly, the CP‐OLEDs exhibit good performances with an external quantum efficiency of 30.1 % and |gEL| factors of 1.2×10−3. [ABSTRACT FROM AUTHOR]

Dynamic chemistry utilizing both covalent and noncovalent bonds provides valid protocols in manipulating properties of self‐assemblies and functions. Here we employ dynamic chemistry to realize multiple‐route control over supramolecular chirality up to five states. N‐protected fluorinated phenylalanine in the carboxylate state self‐assembled into achiral nanoparticles ascribed to the amphiphilicity. Protonation promoted one‐dimensional growth into helices with shrunk hydrophilicity, which in the presence of disulfide pyridine undergo chirality inversion promoted by the hydrogen bonding‐directed coassembly. Further interacting with the water‐soluble reductant cleavages the disulfide bond to initiate the rearrangement of coassemblies with a chirality inversion as well. Finally, by tuning the pH environments, aromatic nucleophilic substitution reaction between reduced products and perfluorinated phenylalanine occurs, giving distinct chiral nanoarchitectures with emerged luminescence and circularly polarized luminescence. We thus realized a particular five‐state control by combining dynamic chemistry at one chiral compound, which greatly enriches the toolbox in fabricating responsive chiroptical materials. [ABSTRACT FROM AUTHOR]

We report a synthetic approach to π‐expanded [6]helicenes incorporating tropone and azocine units in combination with a 5‐membered ring, which exhibit intriguing structural, electronic, and chiroptical properties. The regioselective Beckmann rearrangement allows the isolation of helical scaffolds containing 8‐membered lactam, azocine, and amine units. As shown by X‐ray crystallographic analysis, the incorporation of tropone or azocine units leads to highly distorted [6]helicene moieties, with distinct packing motifs in the solid state. The compounds exhibit promising optoelectronic properties with considerable photoluminescence quantum yields and tunable emission wavelengths depending on the relative position of the nitrogen center within the polycyclic framework. Separation of the enantiomers by chiral high‐performance liquid chromatography (HPLC) allowed characterization of their chiroptical properties by circular dichroism (CD) and circularly polarized luminescence (CPL) spectroscopy. The azocine compounds feature manifold redox chemistry, allowing for the characterization of the corresponding radical anions and cations as well as the dications and dianions, with near‐infrared (NIR) absorption bands extending beyond 3000 nm. Detailed theoretical studies provided insights into the aromaticity evolution upon reduction and oxidation, suggesting that the steric strain prevents the azocine unit from undergoing aromatization, while the indene moiety dominates the observed redox chemistry. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed enantioselective C(sp3)−H functionalization reactions has attracted considerable attention due to its ability for the synthesis of enantiomerically enriched molecules and stimulation of novel retrosynthetic disconnections. Understanding the reaction mechanism, especially the stereochemical process of the reaction, is crucial for the rational design of more efficient catalytic systems. Previously, we developed a Pd(II)/sulfoxide‐2‐hydroxypridine (SOHP) catalytic system for asymmetric C(sp3)−H functionalization reactions. In this study, we focused on unraveling the chemistry of chiral palladacycles involved in the Pd(II)‐catalyzed enantioselective C(sp3)−H functionalization. We have isolated key palladacycle intermediates involved in the enantioselective β‐C(sp3)−H arylation of carboxylic acids catalyzed by the Pd(II)/SOHP system. These palladacycles, exhibiting ligand‐induced chirality, provided a significant opportunity to investigate the stereochemical process and the ligand effect in this asymmetric C−H functionalization. Our investigation provided direct evidence for the C−H palladation step as the enantioselectivity‐determining step, which forms diastereomeric palladacycles that exhibited preservation of chirality in the functionalization step. DFT calculations provided insights into the chiral induction in palladacycle formation. This work highlights the value of chiral palladacycle chemistry in offering mechanistic insights into the Pd(II)‐catalyzed asymmetric C(sp3)−H functionalization reactions. [ABSTRACT FROM AUTHOR]

The construction of olefin‐linked chiral covalent organic frameworks (COFs) with high crystallinity is highly desirable while remains great challenge due to the poor reversibility of the formation reaction for the olefin linkages during the in situ structural self‐healing process. Herein, we successfully synthesized two sets of enantiomeric olefin‐linked COFs. The chiral catalytic groups are uniformly distributed on the pore walls of COFs, resulting in the full exposure of catalytic sites to the reactants in asymmetric catalysis. The as‐prepared (R)/(S)‐CCOF8 exhibits excellent catalytic performance with exceeding 99 % enantiomeric excess in the enantioselective electrophilic amination reaction. Moreover, the heterogeneous chiral catalysts are conveniently recycled and could maintain the performance after ten catalytic cycles. Our findings expand the scope to construct stable and crystalline chiral COFs for the asymmetric catalysis. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL)‐active materials are increasingly recognized for their potential applications such as 3D imaging, data storage, and optoelectronic devices. Typically, CPL materials have required high‐energy (HE) photons for excitation to emit low‐energy (LE) circularly polarized light, a process known as downshifting CPL (DSCPL). However, the emergence of upconverted CPL (UCCPL), where the absorption of multi LE photons results in the emission of a single HE photon with circular polarization, has recently attracted considerable attention. This minireview highlights the intricate relationship between upconversion and CPL phenomena. During upconversion, the dissymmetry factor (glum) value can be improved in certain systems. Additionally, the integration of both LE and HE photons in upconversion‐downshifting‐synergistic systems offers avenues for dual‐excitation or dual‐emission CPL functionalities. More in detail, the emerging UCCPL based on various photon upconversion mechanisms and their synergy with DSCPL are introduced. Additionally, several examples that demonstrate the applications of UCCPL are presented to highlight the future opportunities. [ABSTRACT FROM AUTHOR]

Featuring diverse structural motions/changes, dynamic molecular systems hold promise for executing complex tasks. However, their structural complexity presents formidable challenge in elucidating their kinetics, especially when multiple structural motions are intercorrelated. We herein introduce a twin‐cavity cage that features interconvertible C3‐ and C1‐configurations, with each configuration exhibiting interchangeable P‐ and M‐conformations. This molecule is therefore composed of four interconnected chiral species (P)‐C3, (M)‐C3, (P)‐C1, (M)‐C1. We showcase an effective approach to decouple these sophisticated structural changes into two kinetically distinct pathways. Utilizing time‐dependent 1H NMR spectroscopy at various temperatures, which disregards the transition between mirror‐image conformations, we first determine the rate constant (kc) for the C3‐ to C1‐configuration interconversion, while time‐dependent circular dichroism spectroscopy at different temperatures quantifies the observed rate constant (kobs) of the ensemble of all the structural changes. As kobs≫ ${{\rm { \gg }}}$ kc, it allows us to decouple the overall molecular motions into a slow configurational transformation and rapid conformational interconversions, with the latter further dissected into two independent conformational interchanges, namely (P)‐C3←→ ${ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }$ (M)‐C3 and (P)‐C1←→ ${ \mathbin{{\stackrel{\textstyle\rightarrow} { {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}} } }} }$ (M)‐C1. This work, therefore, sheds light on the comprehensive kinetic study of complex molecular dynamics, offering valuable insights for the rational design of smart dynamic materials for applications of sensing, separation, catalysis, molecular machinery, etc. [ABSTRACT FROM AUTHOR]

Piano stool complexes have been studied over many years and found widespread applications in organic synthesis, catalysis, materials and drug development. We now report the first examples of quantitative chiroptical molecular recognition of chiral compounds through click‐like η6‐arene coordination with readily available half sandwich complexes. This conceptually new approach to chirality sensing is based on irreversible acetonitrile displacement of [Cp*Ru(CH3CN)3]PF6 by an aromatic target molecule, a process that is fast and complete within a few minutes at room temperature. The metal coordination coincides with characteristic circular dichroism inductions that can be easily correlated to the absolute configuration and enantiomeric ratio of the bound molecule. A relay assay that decouples the determination of the enantiomeric composition and of the total sample amount by a practical CD/UV measurement protocol was developed and successfully tested. The introduction of piano stool complexes to the chiroptical sensing realm is mechanistically unique and extends the scope of currently known methods with small‐molecule probes that require the presence of amino, alcohol, carboxylate or other privileged functional groups for binding of the target compound. A broad application range including pharmaceutically relevant multifunctional molecules and the use in chromatography‐free asymmetric reaction analysis are also demonstrated. [ABSTRACT FROM AUTHOR]

Handedness is an essential attribute of chiral nanocrystals, having a major influence on their properties. During chemical growth, the handedness of nanocrystals is usually tuned by selecting the corresponding enantiomer of chiral molecules involved in asymmetric growth, often known as chiral inducers. We report that, even using the same chiral inducer enantiomer, the handedness of chiral gold nanocrystals can be reversed by using Au nanorod seeds with either single crystalline or pentatwinned structure. This effect holds for chiral growth induced both by amino acids and by chiral micelles. Although it was challenging to discern the morphological handedness for L‐cystine‐directed particles, even using electron tomography, both cases showed circular dichroism bands of opposite sign, with nearly mirrored chiroptical signatures for chiral micelle‐directed growth, along with quasi‐helical wrinkles of inverted handedness. These results expand the chiral growth toolbox with an effect that might be exploited to yield a host of interesting morphologies with tunable optical properties. [ABSTRACT FROM AUTHOR]

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one‐dimensional hybrid chiral manganese(II) chloride single crystals, R/S‐(3‐methyl piperidine)MnCl3 (R/S‐1) and R/S‐(3‐hydroxy piperidine)MnCl3 (R/S‐2), crystallizing in the non‐centrosymmetric space group P212121. In comparison to R/S‐1, R/S‐2 single crystals not only show red emission with near‐unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10−3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S‐(3‐hydroxy piperidine) cations and [MnCl6]4− chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4− luminophores induced by N−H⋅⋅⋅Cl hydrogen bonding with R/S‐(3‐hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light‐emitting diodes and X‐ray scintillators. This work shows a highly efficient photoluminescent Mn‐based halide and offers a strategy for designing multifunctional chiral metal halides. [ABSTRACT FROM AUTHOR]

Molecular scaffolds that enable the combinatorial synthesis of new supramolecular building blocks are promising targets for the construction of functional molecular systems. Here, we report a supramolecular scaffold based on boroxine that enables the formation of chiral and ordered 1D supramolecular polymers, which can be easily functionalized for circularly polarized luminescence. The boroxine monomers are quantitatively synthesized in situ, both in bulk and in solution, from boronic acid precursors and cooperatively polymerize into 1D helical aggregates stabilized by threefold hydrogen‐bonding and π–π stacking. We then demonstrate amplification of asymmetry in the co‐assembly of chiral/achiral monomers and the co‐condensation of chiral/achiral precursors in classical and in situ sergeant‐and‐soldiers experiments, respectively, showing fast boronic acid exchange reactions occurring in the system. Remarkably, co‐condensation of pyrene boronic acid with a hydrogen‐bonding chiral boronic acid results in chiral pyrene aggregation with circularly polarized excimer emission and g‐values in the order of 10−3. Yet, the electron deficiency of boron in boroxine makes them chemically addressable by nucleophiles, but also sensitive to hydrolysis. With this sensitivity in mind, we provide first insights into the prospects offered by boroxine‐based supramolecular polymers to make chemically addressable, functional, and adaptive systems. [ABSTRACT FROM AUTHOR]

Addressing the dual enhancement of circular polarization (glum) and luminescence quantum yield (QY) in circularly polarized luminescence (CPL) systems poses a significant challenge. In this study, we present an innovative strategy utilizing the entropically driven self‐assembly of amphiphilic phosphorescent platinum(II) complexes (L−Pt) with tetraethylene glycol chains, resulting in unique temperature dependencies. The entropically driven self‐assembly of L−Pt leads to a synergistic improvement in phosphorescence emission efficiency (QY was amplified from 15 % at 25 °C to 53 % at 60 °C) and chirality, both in the ground state and the excited state (glum value has been magnified from 0.04×10−2 to 0.06) with increasing temperature. Notably, we observed reversible modulation of phosphorescence and chirality observed over at least 10 cycles through successive heating and cooling, highlighting the intelligent control of luminescence and chiroptical properties by regulating intermolecular interactions among neighboring L−Pt molecules. Importantly, the QY and glum of the L−Pt assembly in solid state were measured as 69 % and 0.16 respectively, representing relatively high values compared to most self‐assembled CPL systems. This study marks the pioneering demonstration of dual thermo‐enhancement of phosphorescence and CPL and provides valuable insights into the thermal effects on high‐temperature and switchable CPL materials. [ABSTRACT FROM AUTHOR]

Optically active π‐conjugated polymers (OACPs) have garnered increasing research interest for their resemblance to biological helices and intriguing chirality‐related functions. Traditional methods for synthesizing involve decorating achiral conjugated polymer architectures with enantiopure side substituents through complex organic synthesis. Here, we report a new approach: the templated synthesis of unsubstituted OACPs via supramolecularly confined polymerizations of achiral monomers within nanopores of 2D or 3D chiral covalent organic frameworks (CCOFs). We show that the chiral π‐rich nanospaces facilitate the in situ enantiospecific polymerization and self‐propagation, akin to nonenzymatic polymerase chain reaction (PCR) system, resulting in chiral imprinting. The stacked polymer chains are kinetically inert enough to memorize the chiral information after liberating from CCOFs, and even after treatment at temperature up to 200 °C. The isolated OACPs demonstrate robust enantiodiscrimination, achieving up to 85 % ee in separating racemic amino acids. This underscores the potential of utilizing CCOFs as templates for supramolecularly imprinting optical activity into CPs, paving the way for synthetic evolution and advanced functional exploration of OACPs. [ABSTRACT FROM AUTHOR]

Carotenoids tend to form supramolecular aggregates via non‐covalent interactions where the chirality of individual molecules is amplified to the macroscopic level. We show that this can also be achieved for non‐chiral carotenoid monomers interacting with polysaccharides. The chirality induction in canthaxanthin (CAX), caused by heparin (HP) and hyaluronic acid (HA), was monitored by chiroptical spectroscopy. Electronic circular dichroism (ECD) and Raman optical activity (ROA) spectra indicated the presence of multiple carotenoid formations, such as H‐ and J‐type aggregates. This is consistent with molecular dynamics (MD) and density functional theory (DFT) simulations of the supramolecular structures and their spectroscopic response. [ABSTRACT FROM AUTHOR]

Enantiomerically pure organoperoxides serve as valuable precursors in organic transformations. Herein, we present the first examples of unspecific peroxygenase catalyzed kinetic resolution of racemic organoperoxides through asymmetric reduction. Through meticulous investigation of the reaction conditions, it is shown that the unspecific peroxygenase from Agrocybe aegerita (AaeUPO) exhibits robust catalytic activity in the kinetic resolution reactions of the model substrate with turnover numbers up to 60000 and turnover frequency of 5.6 s−1. Various aralkyl organoperoxides were successfully resolved by AaeUPO, achieving excellent enantioselectivities (e.g. up to 99 % ee for the (S)‐organoperoxide products). Additionally, we screened commercial peroxygenase variants to obtain the organoperoxides with complementary chirality, with one mutant yielding the (R)‐products. While unspecific peroxygenases have been extensively demonstrated as a powerful oxidative catalysts, this study highlights their usefulness in catalyzing the reduction of organoperoxides and providing versatile chiral synthons. [ABSTRACT FROM AUTHOR]

The chiral organic–inorganic halide perovskites (OIHPs) are vital candidates for superior nonlinear optical (NLO) effects associated with circularly polarized (CP) light. NLO in chiral materials often couples with magnetic dipole (MD) transition, as well as the conventional electric dipole (ED) transition. However, the importance of MD transition in NLO process of chiral OIHPs has not yet been well recognized. Here, the circular polarized probe analysis of second harmonic generation circular dichroism (SHG‐CD) provides the direct evidence that the contribution of MD leads to a large anisotropic response to CP lights in chiral OIHPs, (R‐/S‐MBACl)2PbI4. The thin films exhibit great sensitivity to CP lights over a wide wavelength range, and the g‐value reaches up to 1.57 at the wavelength where the contribution of MD is maximized. Furthermore, it is also effective as CP light generator, outputting CP‐SHG with maximum g‐factor of 1.76 upon the stimulation of linearly polarized light. This study deepens the understanding of relation between chirality and magneto‐optical effect, and such an efficient discrimination and generation of CP light signal is highly applicable for chirality‐based sensor and optical communication devices. [ABSTRACT FROM AUTHOR]

Generating circularly polarized luminescence (CPL) with simultaneous high photoluminescence quantum yield (PLQY) and dissymmetry factor (glum) is difficult due to usually unmatched electric transition dipole moment (μ) and magnetic transition dipole moment (m) of materials. Herein we tackle this issue by playing a "cascade cationic insertion" trick to achieve strong CPL (with PLQY of ~100 %) in lead‐free metal halides with high glum values reaching −2.3×10−2 without using any chiral inducers. Achiral solvents of hydrochloric acid (HCl) and N, N‐dimethylformamide (DMF) infiltrate the crystal lattice via asymmetric hydrogen bonding, distorting the perovskite structure to induce the "intrinsic" chirality. Surprisingly, additional insertion of Cs+ cation to substitute partial (CH3)2NH2+ transforms the chiral space group to achiral but the crystal maintains chiroptical activity. Further doping of Sb3+ stimulates strong photoluminescence as a result of self‐trapped excitons (STEs) formation without disturbing the crystal framework. The chiral perovskites of indium‐antimony chlorides embedded on LEDs chips demonstrate promising potential as CPL emitters. Our work presents rare cases of chiroptical activity of highly luminescent perovskites from only achiral building blocks via spontaneous resolution as a result of symmetry breaking. [ABSTRACT FROM AUTHOR]

The analysis of the absolute configuration, enantiomeric composition, and concentration of chiral compounds are frequently encountered tasks across the chemical and health sciences. Chiroptical sensing methods can streamline this work and allow high‐throughput screening with remarkable reduction of operational time and cost. During the last few years, significant methodological advances with innovative chirality sensing systems, the use of computer‐generated calibration curves, machine learning assistance, and chemometric data processing, to name a few, have emerged and are now matched with commercially available multi‐well plate CD readers. These developments have reframed the chirality sensing space and provide new opportunities that are of interest to a large group of chemists. This review will discuss chirality sensing strategies and applications with representative small‐molecule CD sensors. Emphasis will be given to important milestones and recent advances that accelerate chiral compound analysis by outperforming traditional methods, conquer new directions, and pioneering efforts that lie at the forefront of chiroptical high‐throughput screening developments. The goal is to provide the reader with a thorough understanding of the current state and a perspective of future directions of this rapidly emerging field. [ABSTRACT FROM AUTHOR]

Expanded azahelicenes, as heteroanalogues of helically chiral helicenes, hold significant potential for chiroptical materials. Nevertheless, their investigation and research have remained largely unexplored. Herein, we present the facile synthesis of a series of expanded azahelicenes NHn (n=1–5) consisting of 11, 19, 27, 35, and 43 fused rings, mainly by Suzuki coupling followed by Bi(OTf)3‐mediated cyclization of vinyl ethers. The structures of NH2, NH3 and NH4 were confirmed through X‐ray crystallography analysis, and their (P)‐ and (M)‐ enantiomers were also isolated with chiral high performance liquid chromatography. The enantiomers exhibit large absorption (abs) and luminescence (lum) dissymmetry factors, with |gabs|max=0.044; |glum|max=0.003 for NH2, |gabs|max=0.048; |glum|=0.014 for NH3, and |gabs|max=0.043; |glum|max=0.021 for NH4, which are superior to their respective all‐carbon analogues. [ABSTRACT FROM AUTHOR]

The transmission of chiral information between the molecular, meso and microscopic scales is a facet of biology that remains challenging to understand mechanistically and to mimic with artificial systems. Here we demonstrate that the dynamic change in the expression of the chirality of a rotaxane can be transduced into a change in pitch of a soft matter system. Shuttling the position of the macrocycle from far‐away‐from to close‐to a point‐chiral center on the rotaxane axle changes the expression of the chiral information that is transmitted across length scales; from nanometer scale constitutional chirality that affects the conformation of the macrocycle, to the centimeter scale chirality of the liquid crystal phase, significantly changing the pitch length of the chiral nematic structure. [ABSTRACT FROM AUTHOR]

Conformational flexibility and chirality both play a key role in molecular recognition. It is therefore very useful to develop spectroscopic methods that simultaneously probe both properties. It has been theoretically predicted that photoelectron circular dichroism (PECD) should be very sensitive to conformational isomerism. However, experimental proof has been less forthcoming and only exists for a very few favorable cases. Here, we present a new PECD scheme based on resonance‐enhanced two‐photon ionization (RE2PI) using UV/Vis nanosecond laser excitations. The spectral resolution obtained thereby guarantees conformer‐selectivity by inducing resonant conformer‐specific ππ* S1←S0 transitions. We apply this experimental scheme to the study of chiral 1‐indanol, which exists in two conformers linked by a ring inversion and defined by the position of the hydroxyl group, namely axial and equatorial. We show that the PECD of the equatorial and axial forms considerably differ in sign, magnitude and shape. We also discuss the influence of the total ionization energy, vibronic excitation of intermediate and final states, and relative polarization of the excitation and ionization lasers. Conformer‐specificity adds a new dimension to the applications of PECD in analytical chemistry addressing now the general case of floppy systems. [ABSTRACT FROM AUTHOR]

Chiral nanoscale enantiomers exhibit different biological effects in living systems. However, their chirality effect on the detection sensitivity for chiral biological targets still needs to be explored. Here, we discovered that Co2+ can modulate the luminescence performance of L/D‐glutathione (GSH)‐modified copper nanoclusters (L/D−Cu NCs) and induce strong chiroptical activities as the asymmetric factor was enhanced 223‐fold with their distribution regulating from the ultraviolet to visible region. One Co2+ coordinated with two GSH molecules that modified on the surface of Cu NCs in the way of CoN2O2. On this basis, dual‐modal chiral and luminescent signals of Co2+ coordinated L/D−Cu NCs (L/D−Co−Cu NCs) were used to detect the chiral adenosine triphosphate (ATP) based on the competitive interaction between surficial GSH and ATP molecules with Co2+. The limits of detection of ATP obtained with fluorescence and circular dichroism intensity were 9.15 μM and 15.75 nM for L−Co−Cu NCs, and 5.35 μM and 4.69 nM for D−Co−Cu NCs. This demonstrated that selecting suitable chiral configurations of nanoprobes effectively enhances detection sensitivity. This study presents not only a novel method to modulate and enhance the chiroptical activity of nanomaterials but also a unique perspective of chirality effects on the detection performances for bio‐targets. [ABSTRACT FROM AUTHOR]

The racemization of chiral organic compounds is a common chemical phenomenon. However, it often poses configurational‐stability issues to the application of this class of compounds. Achieving chiral organic compounds without the risk of racemization is fascinating, but it is challenging due to a lack of strategies. Here, we reveal the cove‐regions bridging strategy for achieving persistently chiral multi‐helicenes (incapable of racemization), based on the synthesized proof‐of‐concept double hetero[4]helicenes featuring macrocycle structures with a small 3D cavity. Additionally, we demonstrate that the strategy is also effective in tuning the electronic structures of multi‐helicenes, resulting in a conversion from luminescence silence into thermally activated delayed fluorescence (TADF) for the present system. Furthermore, red circularly polarized TADF based on small double [4]helicene systems is achieved for the first time using this strategy. The disclosed cove‐regions bridging strategy provides an opportunity to modulate the electronic structures and luminescent properties of multi‐helicenes without concern for racemization, thus significantly enhancing the structural and property diversity of multi‐helicenes for various applications. [ABSTRACT FROM AUTHOR]

Incorporating chiral elements in host–guest systems currently attracts much attention because of the major impact such structures may have in a wide range of applications, from pharmaceuticals to materials science and beyond. Moreover, the development of multi‐responsive and ‐functional systems is highly desirable since they offer numerous benefits. In this context, we describe herein the construction of a metal‐driven self‐assembled cage that associates a chiral truxene‐based ligand and a bis‐ruthenium complex. The maximum separation between both facing chiral units in the assembly is fixed by the intermetallic distance within the lateral bis‐ruthenium complex (8.4 Å). The resulting chiral cavity was shown to encapsulate polyaromatic guest molecules, but also to afford a chiral triply interlocked [2]catenane structure. The formation of the latter occurs at high concentration, while its disassembly could be achieved by the addition of a planar achiral molecule. Interestingly the planar achiral molecule exhibits induced circular dichroism signature when trapped within the chiral cavity, thus demonstrating the ability of the cage to induce supramolecular chirogenesis. [ABSTRACT FROM AUTHOR]

Achieving circularly polarized organic ultralong room‐temperature phosphorescence (CP‐OURTP) with a high luminescent dissymmetry factor (glum) is crucial for diverse optoelectronic applications. In particular, dynamically controlling the dissymmetry factor of CP‐OURTP can profoundly advance these applications, but it is still unprecedented. This study introduces an effective strategy to achieve photoirradiation‐driven chirality regulation in a bilayered structure film, which consists of a layer of soft helical superstructure incorporated with a light‐driven molecular motor and a layer of room‐temperature phosphorescent (RTP) polymer. The prepared bilayered film exhibits CP‐OURTP with an emission lifetime of 805 ms and a glum value up to 1.38. Remarkably, the glum value of the resulting CP‐OURTP film can be reversibly controlled between 0.6 and 1.38 over 20 cycles by light irradiation, representing the first example of dynamically controlling the glum in CP‐OURTP. [ABSTRACT FROM AUTHOR]

Due to their broken symmetry, chiral plasmonic nanostructures have unique optical properties and numerous applications. However, there is still a lack of comprehension regarding how chirality transfer occurs between circularly polarized light (CPL) and these structures. Here, we thoroughly investigate the plasmon‐assisted growth of chiral nanoparticles from achiral Au nanocubes (AuNCs) via CPL without the involvement of any chiral molecule stimulators. We identify the structural chirality of our synthesized chiral plasmonic nanostructures using circular differential scattering (CDS) spectroscopy, which is correlated with scanning electron microscopy imaging at both the single‐particle and ensemble levels. Theoretical simulations, including hot‐electron surface maps, reveal that the plasmon‐induced chirality transfer is mediated by the asymmetric distribution of hot electrons on achiral AuNCs under CPL excitation. Furthermore, we shed light on how this plasmon‐induced chirality transfer can also be utilized for chiral growth in bimetallic systems, such as Ag or Pd on AuNCs. The results presented here uncover fundamental aspects of chiral light‐matter interaction and have implications for the future design and optimization of chiral sensors and chiral catalysis, among others. [ABSTRACT FROM AUTHOR]

The 1,4‐dithiin motif is known for its reversible redox properties to generate radical cations and diradical dications and thus is interesting for organic electronic applications. However, examples where this motif is embedded into chiral larger fused aromatic compounds are very rare. Here we describe the syntheses of several structurally related pyrene fused dithiins and their spectroscopic investigations with a focus on tuning circular dichroism, with respect to the g values, depending on their connectivity. [ABSTRACT FROM AUTHOR]

Helicity is expressed differently in ortho‐ and para‐fused acenes—helicenes and twistacenes, respectively. While the extent of helicity is constant in helicenes, it can be tuned in twistacenes, and the handedness of flexible twistacenes is often determined by more rigid helicenes. Here, we combine helicenes with rigid twistacenes consisting of a tunable degree of twisting, forming helitwistacenes. While the X‐ray structures reveal that the connection does not affect the helicity of each moiety, their electronic circular dichroism (ECD) and circularly polarized luminescence (CPL) spectra are strongly affected by the helicity of the twistacene unit, resulting in solvent‐induced sign inversion. ROESY NMR and TD‐DFT calculations support this observation, which is explained by differences in the relative orientation of the helicene and twistacene moieties. [ABSTRACT FROM AUTHOR]

Chiral perovskites possess a huge applicative potential in several areas of optoelectronics and spintronics. The development of novel lead‐free perovskites with tunable properties is a key topic of current research. Herein, we report a novel lead‐free chiral perovskite, namely (R/S−)ClMBA2SnI4 (ClMBA=1‐(4‐chlorophenyl)ethanamine) and the corresponding racemic system. ClMBA2SnI4 samples exhibit a low band gap (2.12 eV) together with broad emission extending in the red region of the spectrum (∼1.7 eV). Chirality transfer from the organic ligand induces chiroptical activity in the 465–530 nm range. Density functional theory calculations show a Rashba type band splitting for the chiral samples and no band splitting for the racemic isomer. Self‐trapped exciton formation is at the origin of the large Stokes shift in the emission. Careful correlation with analogous lead and lead‐free 2D chiral perovskites confirms the role of the symmetry‐breaking distortions in the inorganic layers associated with the ligands as the source of the observed chiroptical properties providing also preliminary structure‐property correlation in 2D chiral perovskites. [ABSTRACT FROM AUTHOR]

We report the helicoselective and convergent construction of indolohelicenoids with excellent efficiency and stereocontrol. This reaction proceeds through a chiral‐phosphoric‐acid‐catalyzed enantioselective cycloaddition and eliminative aromatization sequence, which can be finely controlled by adjusting the reaction temperature. Mechanistic studies reveal that the chiral phosphoric acid cooperatively serves as both a bifunctional and Brønsted acid catalyst, enabling one‐pot central‐to‐helical chirality conversion. Additionally, the optical properties of the synthesized indolohelicenoids were characterized to explore their potential applications in organic photoelectric materials. [ABSTRACT FROM AUTHOR]