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Comprehensive Summary: Maleimide derivatives are well‐established reactive intermediates also found in natural products, synthetic pharmaceuticals and functional polymers. Their specific reactivity found widespread applications in the field of bioconjugation and allowed for the development of highly selective functionalizations based on simple additions and cycloadditions with the possible control of central and C–N axial chirality. These multisite‐reactive scaffolds have aroused a long‐standing interest throughout the scientific community more particularly as powerful electrophilic partners and more recently as nucleophilic partners in some specific transformations. The persistent interest in these easily accessible synthetic platforms over the last decade has enabled the development of new enantioselective transformations and the major advancements in this field are presented in this review. Key Scientists: [ABSTRACT FROM AUTHOR]

P‐stereogenic phosphines, renowned for their utility as ligands and catalysts, have been instrumental in the field of asymmetric catalysis. However, the catalytic asymmetric synthesis of chiral ligands possessing both axial and phosphine chirality remains a significant challenge. Here, we present the successful demonstration of a Cu‐catalyzed asymmetric C−P construction using in situ generated secondary phosphine and heteroaryl chloride. By introducing a chiral NHC ligand and an achiral diphosphine auxiliary ligand, we effectively alleviated the poisoning effect caused by phosphine(III) compounds and suppressed the nonenantioselective background reaction. The reaction exhibited excellent enantioselectivity, with up to 96 % ee, and good diastereoselectivity, with up to 14 : 1 dr, when employing less sterically hindered secondary phosphines. This particular substrate poses a significant challenge due to its strong poisoning effect in copper catalysis. [ABSTRACT FROM AUTHOR]

Chirality at the metal center is a well‐established concept, exemplified by numerous four‐ and six‐coordinated complexes. Here, a pioneering example of linear chirality‐at‐metal is described: [Ag(NHC)2]+ (NHC=N‐heterocyclic carbene). In solution, stabilizing π‐π interactions preserve the chiral information of the solid state. Consequently, a novel class of atropisomers is identified, whose stereogenicity arises from hindered rotation around a C−Ag−C axis, instead of a typical C−C bond. [ABSTRACT FROM AUTHOR]

Axially chiral furan‐based scaffolds have been recognized as a class of important five‐membered heteroaryl atropisomers, and developing catalytic atroposelective reactions for constructing this class of scaffolds is highly desirable. However, the catalytic atroposelective construction of such scaffolds is rather underdeveloped due to the existence of great challenges such as remote ortho‐substituents and weak configurational stability. To overcome these challenges, synthetic chemists have recently paid great attention to this research field, and a number of axially chiral furan‐based scaffolds have been constructed via catalytic atroposelective reactions using different strategies. This concept summarized these advances in this field and pointed out the remaining challenges, which will promote the further development of this emerging field. [ABSTRACT FROM AUTHOR]

Herein, by connecting chiral bidibenzo[b,d]furan/bidibenzo[b,d]thiophene and multi‐resonance thermally activated delayed fluorescence (MR‐TADF) units, two pairs of intrinsically axial chiral MR‐TADF materials (R/S‐BDBF‐BNO and R/S‐BDBT‐BNO) realize mirror‐symmetric circularly polarized luminescence (CPL) and narrowband emission. The chiral moieties effectively engage in frontier molecular orbital distributions through the establishment of covalent bonds with boron atoms. The proportions of (1,1′‐bidibenzo[b,d]furan)‐2,2′‐diol in the highest occupied and lowest unoccupied natural transition orbitals (HONTO/LUNTO) are 25.3% and 64.7%, respectively. In addition, BDBT‐BNO processes a dual‐channel transition mode, thus the (1,1′‐bidibenzo[b,d]thiophene)‐2,2′‐diol constitutes 22.8%, 24.3% and 54.0%, 46.9% of the distributions of HONTO, HONTO‐1 and LUNTO, LUNTO+1, respectively. The high proportions endow R/S‐BDBF‐BNO and R/S‐BDBT‐BNO with good CPL properties with dissymmetry factors (|gPL|) of 1.7/1.8 × 10−3. Correspondingly, the circularly polarized organic light‐emitting diodes based on the enantiomers exhibit mirror symmetrical circularly polarized electroluminescence with |gEL| factors of 1.5/1.6 × 10−3. Furthermore, the introduction of sulphur atoms enables BDBT‐BNO to have a high maximum external quantum efficiency of 35.7% in device. [ABSTRACT FROM AUTHOR]

Monophosphine ligands based on C−N axially chiral N‐Arylpyrrole backbones are prepared starting from amino acids and evaluated in Pd‐catalyzed asymmetric allylic substitutions. 20.7–99.9% ees are achieved in the reactions of rac‐1,3‐diphenylallyl acetates with O−, N− and C‐nucleophiles. Ligand screening revealed that the steric hindrance from 3‐ or 4‐ position of the pyrrole is crucial for the enantioselectivity of the reaction. The synthetic utilization of the products was demonstrated by the transformation of one product by a gold‐catalyzed oxidative rearrangement reaction. [ABSTRACT FROM AUTHOR]

Visible light‐driven photocatalytic deracemization is highly esteemed as an ideal tool for organic synthesis due to its exceptional atom economy and synthetic efficiency. Consequently, successful instances of deracemization of allenes have been established, where the activated energy of photosensitizer should surpass that of the substrates, representing an intrinsic requirement. Accordingly, this method is not applicable for axially chiral molecules with significantly high triplet energies. In this study, we present a photoredox catalytic deracemization approach that enables the efficient synthesis of valuable yet challenging‐to‐access axially chiral 2‐azaarene‐functionalized quinazolinones. The substrate scope is extensive, allowing for both 3‐axis and unmet 1‐axis assembly through facile oxidation of diverse central chiral 2,3‐dihydroquinazolin‐4(1H)‐ones that can be easily prepared and achieve enantiomer enrichment via deracemization. Mechanistic studies reveal the importance of photosensitizer selection in attaining excellent chemoselectivity and highlight the indispensability of a chiral Brønsted acid in enabling highly enantioselective protonation to accomplish efficient deracemization. [ABSTRACT FROM AUTHOR]

Catalytic enantioselective preparation of alkene atropisomers with multiple stereogenic elements and discovery of their applications have become significant but challenging issues in the scientific community due to the unique structures of this class of atropisomers. We herein report the first catalytic atroposelective preparation of cyclopentenyl[b]indoles, a new kind of alkene atropisomers, with stereogenic point and axial chirality via an unusual rearrangement reaction of 3‐indolylmethanols under asymmetric organocatalysis. Notably, this novel type of alkene atropisomers have promising applications in developing chiral ligands or organocatalysts, discovering antitumor drug candidates and fluorescence imaging materials. Moreover, the theoretical calculations have elucidated the possible reaction mechanism and the non‐covalent interactions to control the enantioselectivity. This approach offers a new synthetic strategy for alkene atropisomers with multiple stereogenic elements, and represents the first catalytic enantioselective rearrangement reaction of 3‐indolylmethanols, which will advance the chemistry of atropisomers and chiral indole chemistry. [ABSTRACT FROM AUTHOR]

Axially chiral biaryl compounds are ubiquitous scaffolds in natural products, bioactive molecules, chiral ligands and catalysts, but biocatalytic methods for their asymmetric synthesis are limited. Herein, we report a highly efficient biocatalytic route for the atroposelective synthesis of biaryls by dynamic kinetic resolution (DKR). This DKR approach features a transient six‐membered aza‐acetal‐bridge‐promoted racemization followed by an imine reductase (IRED)‐catalyzed stereoselective reduction to construct the axial chirality under ambient conditions. Directed evolution of an IRED from Streptomyces sp. GF3546 provided a variant (S‐IRED‐Ss‐M11) capable of catalyzing the DKR process to access a variety of biaryl aminoalcohols in high yields and excellent enantioselectivities (up to 98 % yield and >99 : 1 enantiomeric ratio). Molecular dynamics simulation studies on the S‐IRED‐Ss‐M11 variant revealed the origin of its improved activity and atroposelectivity. By exploiting the substrate promiscuity of IREDs and the power of directed evolution, our work further extends the biocatalysts' toolbox to construct challenging axially chiral molecules. [ABSTRACT FROM AUTHOR]

The intensity and handedness of circularly polarized luminescence (CPL) were successfully controlled by dynamic molecular motion in solutions. Bis(boron difluoride) complexes with chiral salen ligands were synthesized and their photophysical properties were investigated. Although these complexes showed rapid molecular rotation about the C−N bond axis in solution at room temperature, two conformers assigned as atropisomers were observed in the NMR spectra at low temperature. Furthermore, the equilibrium of these atropisomers was found to change depending on the external environment, such as the solvent and temperature, allowing precise control of the intensity and handedness of CPL without luminescence color shifts. Theoretical calculations based on density functional theory (DFT) revealed that intramolecular chiral exciton coupling is the key to changes in CPL properties. [ABSTRACT FROM AUTHOR]

An achiral Cp*Co(III)‐catalyzed enantioselective C−H activation/annulation of chiral sulfoximine‐enabled thioamides with ynamides is presented herein. This method successfully synthesizes axially chiral five‐membered 2‐amidoindenones with good enantiocontrol. Interestingly, the annulation with chiral oxazolidone‐containing ynamides could provide a separable mixture of diastereomers (up to ~10 : 1 dr). Moreover, enantiopure sulfoximines could be recovered with ~99 % purity, making this method practical. DFT studies show valuable insight into the mechanism and origin of asymmetric induction. [ABSTRACT FROM AUTHOR]

Due to their molecular topology, atropisomers serve as highly valuable chiral frameworks for diverse applications across academic research and industry. Despite the availability of numerous established catalytic methods for their synthesis, there is still a high demand for the development of novel and resourceful strategies. In this concept article, we will detail our studies on the use of transient Lewis acid‐base interactions (LABI) as a dynamization strategy for the synthesis of (hetero)biaryl atropisomers by Dynamic Kinetic Resolution (DKR). The formation of cyclic transition states, resulting from the interaction between an acidic functionality and a basic counterpart, plays a key role in facilitating racemization by substantially reducing the barrier to atropisomerization. In this scenario, we have employed transformations aimed at neutralizing the acidic nature of the Lewis acid, ultimately leading to the formation of configurationally stable enantioenriched compounds. The design of substrates and the employment of stereoselective strategies based on transition metal and biocatalysis for their resolution is detailed. Specific emphasis on the preparation of axially chiral motifs commonly found in catalysis or medicinal chemistry will also be given. [ABSTRACT FROM AUTHOR]

Inherently chiral calixarenes have garnered significant attention due to their distinctive properties, yet the development of efficient catalytic asymmetric synthesis methods remains a critical challenge. Herein, we report the asymmetric synthesis of calix[4]arenes featuring inherent or both inherent and axial chirality via a cobalt‐catalyzed C−H activation/annulation strategy in high yield with excellent enantio‐ and diastereoselectivity (up to >99 % ee and >20 : 1 dr). Electrooxidation was also suitable for this transformation to obviate the sacrificial metal oxidants, underscoring the environmentally friendly potential of this approach. A key octahedral cobaltacycle intermediate was synthesized and characterized, providing valuable insights into the mode of enantio‐ and diastereocontrol of this protocol. Noteworthy photoluminescence quantum yields of up to 0.94 were measured, underscoring the potential of these compounds in the domain of organic fluorescent materials. [ABSTRACT FROM AUTHOR]

The dehydro‐Diels–Alder (DDA) reaction is a powerful method for the construction of aromatic compounds. However, the enantioselective DDA reaction has been rarely developed, probably due to the competitive thermal reaction. Herein, we report a copper‐catalyzed enantioselective DDA reaction through vinyl cation pathway. The reaction leads to the atom‐economical synthesis of axially chiral phenyl and indolyl carbazoles in generally excellent yields with good to excellent atroposelectivities. This methodology represents the first example of non‐noble metal‐catalyzed enantioselective DDA reaction. Notably, new chiral ligand and organocatalyst derived from the constructed axially chiral carbazole are demonstrated to be useful in asymmetric catalysis. [ABSTRACT FROM AUTHOR]

A ruthenium‐catalyzed reductive amination via asymmetric transfer hydrogenation (ATH) has been used to perform an efficient dynamic kinetic resolution (DKR) of N‐aryl 2‐formyl pyrroles decorated with a phosphine moiety positioned at the ortho' position. The strategy relies on the labilization of the stereogenic axis in the substrate facilitated by a transient Lewis acid‐base interaction (LABI) between the carbonyl carbon and the phosphorus center. The reaction features broad substrate scope of aliphatic amines and N‐aryl pyrrole scaffolds, and proceeds under very mild conditions to afford P,N atropisomers in good to high yields and excellent enantioselectivities (up to 99 % ee) for both diphenyl and dicyclohexylphosphino derivatives. [ABSTRACT FROM AUTHOR]

Optically active heterodimeric 5,5′-linked bis-isochromans, containing a stereogenic ortho-trisubstituted biaryl axis and up to four chirality centers, were synthesized stereoselectively by using a Suzuki–Miyaura biaryl coupling reaction of optically active isochroman and 1-arylpropan-2-ol derivatives, providing the first access to synthetic biaryl-type isochroman dimers. Enantiomeric pairs and stereoisomers up to seven derivatives were prepared with four different substitution patterns, which enabled us to test how OR, ECD, and VCD measurements and DFT calculations can be used to determine parallel central and axial chirality elements in three isolated blocks of chirality. In contrast to natural penicisteckins A–D and related biaryls, the ECD spectra and OR data of (aS) and (aR) atropodiastereomers did not reflect the opposite axial chirality, but they were characteristic of the central chirality. The atropodiastereomers showed consistently near-mirror-image VCD curves, allowing the determination of axial chirality with the aid of DFT calculation or by comparison of characteristic VCD transitions. [ABSTRACT FROM AUTHOR]

Axially chiral biaryl δ‐amino acids possess significantly different conformational properties and chiral environment from centrally chiral amino acids, therefore, have drawn considerable attention in the fields of synthetic and medicinal chemistry. Herein, a novel chiral phenanthroline‐potassium catalyst has been developed by constructing a well‐organized axially chiral ligand composed of one 1,10‐phenanthroline unit and two axially chiral 1,1′‐bi‐2‐naphthol (BINOL) units. In the presence of this catalyst, good to excellent yields and enantioselectivities (up to 99 % yield, 98 : 2 er) have been achieved in the ring‐opening alcoholytic dynamic kinetic resolution of a variety of biaryl lactams, thereby providing an efficient protocol for catalytic asymmetric synthesis of unnatural axially chiral biaryl δ‐amino acid derivatives. [ABSTRACT FROM AUTHOR]

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA‐approved drugs and experimental molecules, display markedly different biological activities. The time‐dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future. [ABSTRACT FROM AUTHOR]

A highly enantioselective Pd/Bim-catalyzed dearomative Michael reaction applying polycyclic tropones as non-benzenoid aromatic Michael acceptors and arylboronic acids as aryl pronucleophiles has been developed. The bridged biaryls bearing central and axial chirality, including pentacyclic cyclohepta[b]indoles and 6,7-dihydrodibenzo- [a,c][7]annulen-5-ones, are generally generated in good to high yields and excellent enantioselectivities and can be readily transformed into useful derivatives. [ABSTRACT FROM AUTHOR]

The development of efficient synthetic strategies for the preparation of tetrasubstituted N−H pyrrole derivatives, especially in an environmentally benign fashion is important yet challenging. Herein, we report a copper(II)‐catalyzed tandem reaction involving 1,3‐dipolar cycloaddition of α,β‐ynones and glycine iminoesters, followed by copper(II)‐promoted oxidative (air) dehydrogenative aromatization, allowing de novo access to tetrasubstituted N−H pyrroles in up to 81 % yield under green reaction conditions. A possible reaction pathway is tentatively proposed. Finally, fully substituted pyrroles are available by N‐alkylation, and a preliminary phase‐transfer catalytic asymmetric N‐alkylation was also studied to give an axially chiral pyrrole. [ABSTRACT FROM AUTHOR]

Ancistrobrevinium A (1) is the first N-methylated and non-hydrogenated, and thus cationic naphthylisoquinoline alkaloid. It was discovered in the root bark extract of the phytochemically productive West African liana Ancistrocladus abbreviatus (Ancistrocladaceae). Its constitution was elucidated by HR-ESI-MS and 1D and 2D NMR. Due to the steric hindrance in the proximity of the linkage between the naphthalene and isoquinoline parts, the biaryl axis is rotationally hindered. It thus constitutes a stable element of chirality – the only one in the new alkaloid since, different from most other naphthylisoquinoline alkaloids, it has no stereogenic centers. The axial configuration of 1 was assigned by electronic circular dichroism (ECD) investigations, which gave a positive couplet, indicating a 'positive chirality', here corresponding to a P-configuration. Ancistrobrevinium A (1) showed a weak cytotoxic activity against A549 lung cancer cells (IC50 = 50.6 μM). [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]

Developing novel catalysts with potent activity is of great importance in organocatalysis. In this study, we designed and prepared a new class of benzotetramisole Lewis base catalysts (AxBTM) that have both central and axial chirality. This unique feature of these catalysts results in a three‐dimensional microenvironment with multi‐layers of chirality. The performance of the developed catalysts was tested in a series of cycloaddition reactions. These included the AxBTM‐catalyzed (2+2) cycloaddition between α‐fluoro‐α‐aryl anhydride with imines or oxindoles, and the sequential gold/AxBTM‐catalyzed (4+2) cycloaddition of enynamides with pentafluorophenyl esters. The interplay between axial and central chirality had a collaborative effect in regulating the stereochemistry in these cycloadditions, leading to high levels of stereoselectivity that would otherwise be challenging to achieve using conventional BTM catalysts. However, the (2+2) and (4+2) cycloadditions have different predilections for axial and central chirality combinations. [ABSTRACT FROM AUTHOR]

Axially chiral cycloalkylidenes are interesting but less developed axially chiral molecules. Here, a bispidine‐based chiral amine catalytic system was developed to promote efficiently the asymmetric Knoevenagel condensation of N‐protected oxindoles and benzofuranones with 4‐substituted cyclohexanones. A variety of alkylidenecycloalkanes with stable axial chirality were obtained in good yields and fairly good er (enantiomeric ratio). Based on the absolute configuration determination of product and DFT calculations, a possible mechanism of stereoselective induction was proposed. [ABSTRACT FROM AUTHOR]

Axially chiral biaryl ethers and related compounds hold valuable potential in natural products, medicinal chemistry, and catalysis; however, their asymmetric syntheses have always been overlooked compared to other biaryl/hetero-biaryl atropisomers. Unlike the later class molecules bearing a single chiral axis, the former category possesses a unique type of atropisomerism bearing two potential axes. Due to their great importance in diverse research domains, catalytic atropselective biaryl ether synthesis has recently witnessed an upsurge. This highlight article provides an elaborated view on the developments of catalytic synthetic methods that have been explored to achieve dual axial chirality in biaryl ethers and related scaffolds. [ABSTRACT FROM AUTHOR]

A hitherto unknown class of C4‐symmetric Caryl−Cβ (C3, C8, C13, C18) axially chiral porphyrins has been synthesized and the application of their iridium (Ir) complexes in catalytic asymmetric C(sp3)−H functionalization is documented. Cyclotetramerization of enantioenriched axially chiral 2‐hydroxymethyl‐3‐naphthyl pyrroles under mild acidic conditions affords, after oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ), the C4‐symmetric α,α,α,α‐atropenantiomer as an only isolable diastereomer. Both regioisomeric Ir(Por*)(CO)(Cl) complexes catalyze the carbene C−H insertion reaction affording the same enantiomer, albeit with slight difference in enantioselectivity. With the optimum Ir‐complex 3 e, the 2‐substituted arylacetic acid derivatives were generated from diazo compounds and cyclohexadiene in excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

There is a pressing need for methods that can connect enantioenriched organic compounds with readily accessible building blocks via asymmetric functionalization of unreactive chemical bonds in organic synthesis and medicinal chemistry. Herein, the asymmetric chemoselective cleavage of two unactivated C(Ar)−O bonds in the same molecule is disclosed for the first time through an unusual nickel‐catalyzed carbomagnesiation. This reaction facilitates the evolution of a novel atroposelective ring‐opening difunctionalization. Utilizing readily available dibenzo bicyclic substrates, diverse valuable axially chiral biaryls are furnished with high efficiencies. Synthetic elaborations showcase the application potential of this method. The features of this method include good atom‐economy, multiple roles of the nucleophile, and a simple catalytic system that enables the precise magnesiation of an α‐C(Ar)−O bond and arylation of a β‐C(Ar)−O bond. [ABSTRACT FROM AUTHOR]

This document provides a summary of various methods for the synthesis of tetrasubstituted axially chiral alkenes. The methods discussed include urea group-directed organocatalytic dihalogenation, Rh(III)-catalyzed C-H activation and directing group migration, cationic rhodium(I)/H8-BINAP-catalyzed chelation-controlled cycloaddition, Cu/Pd dual catalysis for arylboration, nickel-catalyzed cross-electrophile trans-aryl-benzylation, palladium-catalyzed C-H functionalization, Pd(II)-catalyzed thioether-directed alkenyl C-H olefination, Suzuki-Miyaura cross-coupling, asymmetric N-alkylation, chiral phosphoric acid catalyzed kinetic resolution, and asymmetric allylic substitution-isomerization. The methods demonstrate broad substrate scope and high enantioselectivities, but further research is needed to explore stereodivergent synthesis and applications in pharmaceutical chemistry. [Extracted from the article]

Fagopyrins are phenantroperylenequinones present in the flowers of Fagopyrum esculentum (buckwheat) endowed with photodynamic activity. It has been reported that fagopyrin extracts actually contain a complex mixture of closely related compounds, differing only on the nature of the perylenequinone substituents. We report our systematic and detailed study on the chemical composition of fagopyrin extracts by a combination of preparative and analytical techniques. The combined use of 1H‐NMR and CD spectroscopy was found to be particularly suited to fully characterize all stereochemical aspects of the extracted fagopyrins. For the first time nine isomers have been structurally characterized and their stereochemistry fully elucidated. The presence of two different heterocyclic ring substituents, two stereogenic centers and the inherent axial chirality of the aromatic system provides a complex stereochemical relationships among isomers, thus giving account of the high level of molecular multiplicity found in the extract. [ABSTRACT FROM AUTHOR]

Luminescent organic radicals, especially those with photoactivated circularly polarized luminescence (CPL) features, hold great significance for cutting‐edge optoelectronic applications, but their development still remains a challenge. In this study, we propose a novel strategy to achieve photoactivated CPL radicals by bonding two phosphine centers within an axial chiral system, yielding a compound of R/S‐5,5‐bis(diphenylphosphino)‐4,4′‐bibenzo[d][1,3]dioxole (R/S‐BDP). The photoactivated R/S‐BDP molecules in polymer matrix display a robust quantum yield of 19.8 % and a dissymmetry factor (glum) of 1.2×10−4, marking this work as the first example of photoactivated CPL radicals. Furthermore, the glum is improved to 1.0×10−2 by using a liquid crystal as host. Experimental and theoretical analyses reveal that R/S‐BDP molecules, endowed with double phosphine cores in axial chirality, offer a direct way for intramolecular electron transfer upon photoirradiation. This leads to the generation of radical ionic pairs, which subsequently trigger the donor‐acceptor arrangement through intermolecular electron transfer, thereby resulting in stable radical emission. The extended photoactivated BDP‐F exhibits a remarkably high quantum efficiency of 57.8%. Ultimately, the distinctive photo‐responsive CPL radical luminescence has been successfully used for information displays and anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Upgrading CO2 to value‐added chiral molecules via catalytic asymmetric C−C bond formation is a highly important yet challenging task. Although great progress on the formation of centrally chiral carboxylic acids has been achieved, catalytic construction of axially chiral carboxylic acids with CO2 has never been reported to date. Herein, we report the first catalytic asymmetric synthesis of axially chiral carboxylic acids with CO2, which is enabled by nickel‐catalyzed dynamic kinetic asymmetric reductive carboxylation of racemic aza‐biaryl triflates. A variety of important axially chiral carboxylic acids, which are valuable but difficult to obtain via catalysis, are generated in an enantioconvergent version. This new methodology features good functional group tolerance, easy to scale‐up, facile transformation and avoids cumbersome steps, handling organometallic reagents and using stoichiometric chiral materials. Mechanistic investigations indicate a dynamic kinetic asymmetric transformation process induced by chiral nickel catalysis. [ABSTRACT FROM AUTHOR]

Upgrading CO2 to value‐added chiral molecules via catalytic asymmetric C−C bond formation is a highly important yet challenging task. Although great progress on the formation of centrally chiral carboxylic acids has been achieved, catalytic construction of axially chiral carboxylic acids with CO2 has never been reported to date. Herein, we report the first catalytic asymmetric synthesis of axially chiral carboxylic acids with CO2, which is enabled by nickel‐catalyzed dynamic kinetic asymmetric reductive carboxylation of racemic aza‐biaryl triflates. A variety of important axially chiral carboxylic acids, which are valuable but difficult to obtain via catalysis, are generated in an enantioconvergent version. This new methodology features good functional group tolerance, easy to scale‐up, facile transformation and avoids cumbersome steps, handling organometallic reagents and using stoichiometric chiral materials. Mechanistic investigations indicate a dynamic kinetic asymmetric transformation process induced by chiral nickel catalysis. [ABSTRACT FROM AUTHOR]

Upgrading CO2 to value‐added chiral molecules via catalytic asymmetric C−C bond formation is a highly important yet challenging task. Although great progress on the formation of centrally chiral carboxylic acids has been achieved, catalytic construction of axially chiral carboxylic acids with CO2 has never been reported to date. Herein, we report the first catalytic asymmetric synthesis of axially chiral carboxylic acids with CO2, which is enabled by nickel‐catalyzed dynamic kinetic asymmetric reductive carboxylation of racemic aza‐biaryl triflates. A variety of important axially chiral carboxylic acids, which are valuable but difficult to obtain via catalysis, are generated in an enantioconvergent version. This new methodology features good functional group tolerance, easy to scale‐up, facile transformation and avoids cumbersome steps, handling organometallic reagents and using stoichiometric chiral materials. Mechanistic investigations indicate a dynamic kinetic asymmetric transformation process induced by chiral nickel catalysis. [ABSTRACT FROM AUTHOR]

Upgrading CO2 to value‐added chiral molecules via catalytic asymmetric C−C bond formation is a highly important yet challenging task. Although great progress on the formation of centrally chiral carboxylic acids has been achieved, catalytic construction of axially chiral carboxylic acids with CO2 has never been reported to date. Herein, we report the first catalytic asymmetric synthesis of axially chiral carboxylic acids with CO2, which is enabled by nickel‐catalyzed dynamic kinetic asymmetric reductive carboxylation of racemic aza‐biaryl triflates. A variety of important axially chiral carboxylic acids, which are valuable but difficult to obtain via catalysis, are generated in an enantioconvergent version. This new methodology features good functional group tolerance, easy to scale‐up, facile transformation and avoids cumbersome steps, handling organometallic reagents and using stoichiometric chiral materials. Mechanistic investigations indicate a dynamic kinetic asymmetric transformation process induced by chiral nickel catalysis. [ABSTRACT FROM AUTHOR]

Positive homotropic artificial allosteric systems are important for the regulation of cooperativity, selectivity and nonlinear amplification. Stereodynamic homotropic allosteric receptors can transmit and amplify induced chirality by the first ligand binding to axial chirality between two chromophores. We herein report stereodynamic allosteric urea receptors consisting of a rotational shaft as the axial chirality unit, terphenyl units as structural transmission sites and four urea units as binding sites. NMR titration experiments revealed that the receptor can bind two carboxylate guests in a positive homotropic allosteric manner attributed to the inactivation by intramolecular hydrogen‐bonding between urea units within the receptor. In addition, the VT‐CD spectra observed upon binding of the urea receptor with l‐ or D‐amino acid salts in MeCN showed interesting temperature‐dependent Cotton effects, based on the differences of the receptor shaft unit and the guest structure. The successful discrimination of hydrocarbon‐based side chains of amino acid salts indicated that the input of chiral and steric information for the guest was amplified as outputs of the Cotton effect and the temperature‐dependence of VT‐CD spectra through cooperativity of positive allosteric binding. [ABSTRACT FROM AUTHOR]

4,4′‐Biazulene is a potentially attractive key component of an axially chiral biaryl compound, however, its structure and properties have not been clarified owing to the lack of its efficient synthesis. We report a breakthrough in the reliable synthesis of 4,4′‐biazulene, which is achieved by the access to azulen‐4‐ylboronic acid pinacol ester and 4‐iodoazulene as novel key synthetic intermediates for the Suzuki‐Miyaura cross‐coupling reaction. The X‐ray crystallographic analysis of 4,4′‐biazulene confirmed its axial chirality. The enantiomers of 4,4′‐biazulene were successfully resolved by HPLC on the chiral stationary phase column. The kinetic experiments and DFT calculations indicate that the racemization energy barrier of 4,4′‐biazulene is comparable to that of 1,1′‐binaphthyl. [ABSTRACT FROM AUTHOR]

The Friedel‐Crafts reaction stands as a powerful synthetic tool for C−H functionalization of aromatic feedstocks, which is conventionally realized through electrophilic alkylation and acylation. The burgeoning interests in axially chiral compounds across diverse fields have spurred extensive exploration of this classic transformation for catalytic atroposelective synthesis. Consequently, the past decade has witnessed the rapid expansion of various non‐canonical Friedel‐Crafts reactions, including electrophilic arylation, alkenylation, halogenation, sulfenylation, and amination of aryl C−H bonds, thereby delving into new chemical spaces. A range of catalytic atroposelective synthetic methods have been devised for these significant arene C−H functionalization. This review provides a comprehensive overview of the cutting‐edge catalytic synthesis of atropoisomers through non‐canonical Friedel‐Crafts reactions, categorized into three parts based on the type of bond formation on the aromatics: C(sp2)−C(sp3) bond formations, C(sp2)−C(sp2) bond formations and C(sp2)−heteroatom bond formations. The richness of electrophiles and the modulation of atroposelectivity by diverse chiral organocatalysts, particularly chiral Brønsted acids, are elucidated. We anticipate that the repertoire of asymmetric Friedel‐Crafts reaction will continue to flourish and to be demonstrated in not only scientific researches but also industrial organic synthesis. [ABSTRACT FROM AUTHOR]

Technologies that detect circularly polarized light (CPL), particularly in the UV region, have significant potential for various applications, including bioimaging and optical communication. However, a major challenge in directly sensing CPL arises from the conflicting requirements of planar structures for efficient charge transport and distorted structures for effective interaction with CPL. Here, a novel design of an axially chiral n‐type organic semiconductor is presented to surmount the challenge, in which a binaphthyl group results in a high dissymmetry factor at the molecular level, while maintaining excellent electron‐transporting characteristics through the naphthalene diimide group. Experimental and computational methods reveal different stacking behaviors in homochiral and heterochiral assemblies, yielding different structures: Nanowires and nanoparticles, respectively. Especially, the homochiral assemblies exhibit effective π–π stacking between naphthalene diimides despite axial chirality. Thus, phototransistors fabricated using enantiomers exhibit a high maximum electron mobility of 0.22 cm2 V−1 s−1 and a detectivity of 3.9 × 1012 Jones, alongside the CPL distinguishing ability with a dissymmetry factor of responsivity of 0.05. Furthermore, the material possesses a wide bandgap, contributing to its excellent visible‐blind UV‐selective detection. These findings highlight the new strategy for compact CPL detectors, coupled with the demonstration of less‐explored n‐type and UV region phototransistors. [ABSTRACT FROM AUTHOR]

The article discusses the challenges and opportunities presented by the integration of artificial intelligence (AI) and the Internet of Things (IoT), highlighting the potential benefits for various industries such as healthcare, agriculture, and transportation. It discusses how AI-powered IoT devices can enhance efficiency, productivity, and decision-making processes while also addressing concerns about data privacy and security.

Herein, we report an asymmetric two-component alkenyl Catellani reaction for the construction of C--N axial chirality through a palladium/chiral norbornene cooperative catalysis and an axial-to-axial chirality transfer process. Various partially aromatic iodinated 2-pyridones, quinolones, coumarin and uracil substrates react with 2,6-disubstituted aryl bromides with a tethered amide group, to afford a wide variety of polycyclic C--N atropisomers (38 examples, up to 97% e.e.). The obtained C--N axial chirality originates from the preformed transient C--C axial chirality with high fidelity. The synthetic utility of this chemistry is demonstrated by facile preparation of complex quinoline and pyridine based C--N atropisomers through a N-deprotection and aromatization sequence. In addition, a remote axial-to-central diastereoinduction process dictated by C--N axial chirality is observed with excellent diastereocontrol. [ABSTRACT FROM AUTHOR]

The article focuses on recent advancements in organic synthesis including asymmetric two-component alkenyl Catellani reaction, planar-chiral ligands synthesis for nickel-catalyzed reduction, and enantioselective benzimidazole atropisomer synthesis. It also discusses supported atomically dispersed palladium (Pd) catalysis, hyperconjugation's impact on photovoltaic performance, and atroposelective synthesis of 2-arylindoles using chiral phosphoric acid-catalyzed direct amination of indoles.

The development of new chemically recyclable polymers via monomer design would provide a transformative strategy to address the energy crisis and plastic pollution problem. Biaryl‐fused cyclic esters were targeted to generate axially chiral polymers, which would impart new material performance. To overcome the non‐polymerizability of the biaryl‐fused monomer DBO, a cyclic ester Me‐DBO installed with dimethyl substitution was prepared to enable its polymerizability via enhancing torsional strain. Impressively, Me‐DBO readily went through well‐controlled ring‐opening polymerization, producing polymer P(Me‐DBO) with high glass transition temperature (Tg >100 °C). Intriguingly, mixing these complementary enantiopure polymers containing axial chirality promoted a transformation from amorphous to crystalline material, affording a semicrystalline stereocomplex with a melting transition temperature more than 300 °C. P(Me‐DBO) were capable of depolymerizing back to Me‐DBO in high efficiency, highlighting an excellent recyclability. [ABSTRACT FROM AUTHOR]

Axially chiral architectures exist widely in natural products, biologically relevant molecules, chiral ligands and catalysts as well as functional materials. Therefore, catalytic asymmetric synthesis of atropisomers has become one of the most fast‐growing fields in the community of chemistry and rapid advances have occurred. Among different methods reported, the organocatalytic atroposelective dynamic kinetic resolution (DKR) involving ring manipulations stands out as a cutting‐edge technology to construct axial chirality from the point of atom/step economy. In this DKR strategy, the configurational lability of starting materials originates from chirally‐labile ring structure of cyclic substrates/intermediates or transient ring formation through noncovalent interactions from acyclic substrates. The two atropisomers of starting material are in equilibrium in the reaction medium, ensuring the constant transformation of the less reactive atropisomer into the more reactive one, and then to a single enantiopure product in the presence of an appropriate organocatalyst. This review summarizes recent advancements on this topic, including their scopes, limitations, mechanisms, applications and provides some insights into further developments. [ABSTRACT FROM AUTHOR]

We report herein a chiral CpXRh(III)‐catalyzed domino cyclization/C3‐arylation process using 2‐alkynylanilines and 1‐diazonaphthoquinones as viable substrates, delivering indole‐based derivatives endowed with axial chirality. The method features high enantioselectivity, broad substrate scope, and robust functional group tolerance. Subsequent functionalization of the synthesized scaffolds underlines the practicality of this approach in the design of indole‐derivated axially chiral frameworks, demonstrating its substantial promise in synthetic and medicinal chemistry applications. [ABSTRACT FROM AUTHOR]

Boosting the circularly polarized luminescence of small organic molecules has been a stubborn challenge because of weak structure rigidity and dynamic molecular motions. To investigate and eliminate these factors, here, we carried out the structure‐property relationship studies on a newly‐developed axial chiral scaffold of bidibenzo[b,d]furan. The molecular rigidity was finely tuned by gradually reducing the alkyl‐chain length. The environmental factors were considered in solution, crystal, and polymer matrix at different temperatures. As a result, a significant amplification of the dissymmetry factor glum from 10−4 to 10−1 was achieved, corresponding to the situation from (R)‐4C in solution to (R)‐1C in polymer film at room temperature. A synergistic strategy of increasing the intramolecular rigidity and enhancing the intermolecular interaction to restrict the molecular motions was thus proposed to improve circularly polarized luminescence. The though‐out demonstrated relationship will be of great importance for the development of high‐performance small organic chiroptical systems in the future. [ABSTRACT FROM AUTHOR]

This article explores the use of ionic ligand-substrate interactions in enantioselective palladium-catalyzed Suzuki-Miyaura reactions. Traditionally, stereochemical control in asymmetric catalysis has relied on steric repulsion, but recent research has investigated the use of noncovalent interactions, such as ionic interactions, to enhance stereoselectivity. The article focuses on the challenges and advancements in utilizing ionic interactions in transition-metal catalysis and presents recent work on developing chiral dialkyl biarylphosphine ligands with nonligating ionic groups for long-range stereocontrol in Suzuki-Miyaura reactions. The authors demonstrate the successful creation of chirality at remote quaternary stereocenters through the use of ionic substrate-catalyst interactions. Further research is needed to fully understand the complex networks of ionic interactions and explore the potential of ionic chiral catalysts. [Extracted from the article]

A series of novel thiazine derivatives featuring axial chirality in both (R) and (S) configurations were successfully synthesized by N‐heterocyclic carbene (NHC)‐catalyzed enantioselective [3 + 3] annulations, and their potential as anti‐plant virus agents against potato virus Y (PVY) was evaluated. Biological activity results demonstrated that most of these chiral thiazine derivatives exhibited significant activities against PVY. Notably, compound (S)‐3g displayed a remarkable 58% inactivation effect against PVY at a concentration of 500 μg/mL, slightly surpassing the effectiveness of Ningnanmycin (NNM) at 57%. Additionally, (S)‐3g exhibited curative activity of 57%, which is superior to NNM (53%). Molecular docking studies revealed preliminary insights into the distinct biological properties of the two different enantiomers, (R) or (S)‐3g against PVY, wherein single enantiomer (S)‐3g formed a more stable interaction with PVY‐CP, as indicated by its lower binding free energy (−41.18 kcal/mol) compared to (R)‐3g (−36.9 kcal/mol). The findings in this study with a new class of axially chiral thiazine derivatives shall inspire further development of chiral heterocycles as potential drug candidates for the protection of plant virus infections. [ABSTRACT FROM AUTHOR]

Chiral metallo‐supramolecular fibres can be easily obtained by mixing a chloroform solution of a phenylacetylene monomer (PA) that bears a chiral sulfoxide group as pendant, with different equivalents of a methanolic solution of AgClO4. Thus, while the PA is found molecularly dissolved in chloroform, the addition of Ag+ ions induce its aggregation through the formation of an axially chiral metallo‐supramolecular aggregate with high thermal stable properties. In this case, the ability of the metal ion to coordinate the PA triple bond, combined with the argentophilicity of the metal ion and the planarity of the phenylacetylene drives to the formation of a helical coordination polymer, whose P or M axial chirality is determined by the chirality of the sulfoxide used as substituent of the PA. Depending on the PA/Ag+ (mol/mol) ratio, it is possible to tune the morphology of the metallo‐supramolecular aggregate from chiral fibers to chiral gel. [ABSTRACT FROM AUTHOR]

In the chemistry community, catalytic asymmetric synthesis of furan‐based compounds bearing both axial and central chirality has proven to be a significant but challenging issue owing to the importance and difficulty in constructing such frameworks. In this work, we have realized the first catalytic asymmetric synthesis of five‐five‐membered furan‐based compounds bearing both axial and central chirality via organocatalytic asymmetric (2+4) annulation of achiral furan‐indoles with 2,3‐indolyldimethanols with uncommon regioselectivity. By this strategy, furan‐indole compounds bearing both axial and central chirality were synthesized in high yields with excellent regio‐, diastereo‐, and enantioselectivities. Moreover, theoretical calculations were conducted to provide an in‐depth understanding of the reaction pathway, activation mode, and the origin of the selectivity. [ABSTRACT FROM AUTHOR]

A highly enantioselective biocatalytic dynamic kinetic resolution (DKR) of 2‐(quinoline‐8‐yl) 3‐methylbenzaldehydes and 1‐naphthaldehydes is described. The reaction proceeds by atroposelective carbonyl reduction catalyzed by commercial ketoreductases (KREDs), generally reaching high conversions and excellent enantiomeric excesses. Both atropoisomers of the final alcohols can be obtained by a proper selection of the biocatalyst. The DKR strategy relies in the racemization of the stereogenic axis that takes place thanks to a transient Lewis acid‐base interaction (LABI) between the nitrogen in the quinoline and the carbonyl group. [ABSTRACT FROM AUTHOR]