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Biological systems are homochiral, raising the question of how a racemic mixture of prebiotically synthesized biomolecules could attain a homochiral state at the network level. Based on our recent results, we aim to address a related question of how chiral information might have flowed in a prebiotic network. Utilizing the crystallization properties of the central ribonucleic acid (RNA) precursor known as ribose-aminooxazoline (RAO), we showed that its homochiral crystals can be obtained from its fully racemic solution on a magnetic mineral surface due to the chiral-induced spin selectivity (CISS) effect [Ozturk et al., arXiv:2303.01394 (2023)]. Moreover, we uncovered a mechanism facilitated by the CISS effect through which chiral molecules, such as RAO, can uniformly magnetize such surfaces in a variety of planetary environments in a persistent manner [Ozturk et al., arXiv:2304.09095 (2023)]. All this is very tantalizing because recent experiments with tRNA analogs demonstrate high stereoselectivity in the attachment of L-amino acids to D-ribonucleotides, enabling the transfer of homochirality from RNA to peptides [Wu et al., J. Am. Chem. Soc. 143, 11836 (2021)]. Therefore, the biological homochirality problem may be reduced to ensuring that a single common RNA precursor (e.g., RAO) can be made homochiral. The emergence of homochirality at RAO then allows for the chiral information to propagate through RNA, then to peptides, and ultimately through enantioselective catalysis to metabolites. This directionality of the chiral information flow parallels that of the central dogma of molecular biology—the unidirectional transfer of genetic information from nucleic acids to proteins [F. H. Crick, in Symposia of the Society for Experimental Biology, Number XII: The Biological Replication of Macromolecules, edited by F. K. Sanders (Cambridge University Press, Cambridge, 1958), pp. 138-163; and F. Crick, Nature 227, 561 (1970)]. [ABSTRACT FROM AUTHOR]

The Wittig reaction is renowned as exceptionally versatile method for converting a diversity of aldehydes and ketones into alkenes. Recently, strategies for chiral phosphine catalysis under PIII/PV=O redox cycling emerged to render this venerable transformation stereoselective. Herein, we describe that phosphine redox catalysis enables the enantioselective synthesis of pertinent biaryl atropisomers by means of a stereocontrolled arene‐forming Wittig reaction. Key to the process is the release of an endogenous base from readily accessible tert‐butyloxycarbonylated Morita–Baylis–Hillman adducts triggered by catalyst intramolecularization, permitting mild phosphine redox catalysis for atroposelective Wittig reactions. By this strategy, a broad diversity of biaryl atropisomers is obtained with up to 94 : 6 enantioselectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] Understanding the structure-function relationships encoded on chiral catalysts is important for investigating the fundamental principles of catalytic enantioselectivity. Herein, the synthesis and self-assembly of naphthalene substituted bis - l / d -histidine amphiphiles (bis - l / d - NapHis) in DMF/water solution mixture is reported. The resulting supramolecular assemblies featuring well-defined P/M nanoribbons (NRs). With combination of the (P/M)-NR and metal ion catalytic centers (M n+ = Co2+, Cu2+, Fe3+), the (P)-NR-M n+ as chiral supramolecular catalysts show catalytic preference to 3,4-dihydroxy- S -phenylalanine (S -DOPA) oxidation while the (M)-NR-M n+ show enantioselective bias to R -DOPA oxidation. In contrast, their monomeric counterparts bis - l / d - NapHis-M n+ display an inverse and dramatically lower catalytic selectivity in the R/S -DOPA oxidation. Among them, the Co2+-coordinated supramolecular nanostructures show the highest catalytic efficiency and enantioselectivity (select factor up to 2.70), while the Fe3+-coordinated monomeric ones show nearly racemic products. Analysis of the kinetic results suggests that the synergistic effect between metal ions and the chiral supramolecular NRs can significantly regulate the enantioselective catalytic activity, while the metal ion-mediated monomeric bis - l / d - NapHis were less active. The studies on association constants and activation energies reveal the difference in catalytic efficiency and enantioselectivity resulting from the different energy barriers and binding affinities existed between the chiral molecular/supramolecular structures and R/S -DOPA enantiomers. This work clarifies the correlation between chiral molecular/supramolecular structures and enantioselective catalytic activity, shedding new light on the rational design of chiral catalysts with outstanding enantioselectivity. [ABSTRACT FROM AUTHOR]

Herein we report a catalytic enantioselective (3+2) annulation, in which a vinyl phosphonium intermediate serves as the 2‐carbon component. The reaction involves an α‐umpolung β‐umpolung coupling sequence, enabled by β‐haloacrylates and chiral enantioenriched phosphepine catalysts. The reaction shows good generality, providing access to an array of cyclopentenes, with mechanistic studies supporting stereospecific formation of the vinyl phosphonium intermediate which, then undergoes annulation with turn over limiting catalyst elimination. Beyond defining a new approach to cyclopentenes, these studies demonstrate that β‐haloacrylates can replace ynoates in reaction designs that require exclusive umpolung coupling at the α‐ and β‐positions. [ABSTRACT FROM AUTHOR]

The inherent chiral structures of DNA serve as attractive scaffolds to construct DNA hybrid catalysts for valuable enantioselective transformations. Duplex and G‐quadruplex DNA‐based enantioselective catalysis has made great progress, yet novel design strategies of DNA hybrid catalysts are highly demanding and atomistic analysis of active centers is still challenging. DNA i‐motif structures could be finely tuned by different cytosine‐cytosine base pairs, providing a new platform to design DNA catalysts. Herein, we found that a human telomeric i‐motif DNA containing cytosine‐silver(I)‐cytosine (C‐Ag+‐C) base pairs interacting with Cu(II) ions (i‐motif DNA(Ag+)/Cu2+) could catalyze Diels–Alder reactions with full conversions and up to 95 % enantiomeric excess. As characterized by various physicochemical techniques, the presence of Ag+ is proved to replace the protons in hemiprotonated cytosine‐cytosine (C : C+) base pairs and stabilize the DNA i‐motif to allow the acceptance of Cu(II) ions. The i‐motif DNA(Ag+)/Cu2+ catalyst shows about 8‐fold rate acceleration compared with DNA and Cu2+. Based on DNA mutation experiments, thermodynamic studies and density function theory calculations, the catalytic center of Cu(II) ion is proposed to be located in a specific loop region via binding to one nitrogen‐7 atom of an unpaired adenine and two phosphate‐oxygen atoms from nearby deoxythymidine monophosphate and deoxyadenosine monophosphate, respectively. [ABSTRACT FROM AUTHOR]

Covalent immobilization of chiral dienes in mesoporous solids for asymmetric heterogeneous catalysis is highly attractive. In order to study confinement effects in bimolecular vs monomolecular reactions, a series of pseudo‐C2‐symmetrical tetrahydropentalenes was synthesized and immobilized via click reaction on different mesoporous solids (silica, carbon, covalent organic frameworks) and compared with homogeneous conditions. Two types of Rh‐catalyzed reactions were studied: (a) bimolecular nucleophilic 1,2‐additions of phenylboroxine to N‐tosylimine and (b) monomolecular isomerization of isoxazole to 2H‐azirne. Polar support materials performed better than non‐polar ones. Under confinement, bimolecular reactions showed decreased yields, whereas yields in monomolecular reactions were only little affected. Regarding enantioselectivity the opposite trend was observed, i. e. effective enantiocontrol for bimolecular reactions but only little control for monomolecular reactions was found. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Porous organic polymers (POPs) have attracted great attention in past decades. Although diverse functional POPs have been developed, multistimuli‐responsive POPs with excellent aggregate‐state luminescence together with good chiroptical properties have rarely been reported. Herein, two pairs of Salen‐type enantiomeric POPs with multistimuli‐responsive luminescence and chiral features were designed and synthesized by facile polycondensation reactions between polyfunctional aggregation‐induced emission luminogen (AIEgen)‐containing salicylaldehyde derivatives and chiral diamines. With Salen units in polymer backbones as tetradentate ligands, a series of POP‐metal complexes were further prepared. The obtained POPs and metal complexes show good porosity, high thermal stability, and obvious circular dichroism signals. Moreover, benefiting from the coexistence of AIEgen and Salen units in polymer structures, these POPs exhibit excellent luminescence performance in aggregate states and tunable fluorescence behaviors in response to external stimuli of Zn2+ ion, mechanical forces, organic solvent, and acids. Due to the dynamic feature of Schiff base C=N bonds, the present POPs can efficiently undergo hydrolysis reactions under strong acidic conditions to reproduce the AIEgen‐ containing monomers, and such an acid‐induced degradation process can be directly visualized and dynamically monitored via fluorescence variation. These properties collectively make the POPs candidate materials for applications in heterogeneous asymmetric catalysis, fluorescence sensing, biomedicine, etc. [ABSTRACT FROM AUTHOR]

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from a newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis and a general approach that enable rapid construction of highly diversified enantioenriched allylic alcohols containing a 1,1‐, 1,2‐disubstituted and trisubstituted alkene as well as axial stereogenicity in up to 99 % yield and 99 : 1 er without the need of preformation of alkenyl–metal reagents. DFT calculations revealed the origin of enantioselectivity. [ABSTRACT FROM AUTHOR]

Asymmetric catalysis for enantioselective intramolecular hydroamination of alkenes is a critical method in the construction of enantioenriched nitrogen-containing rings, often prevalent in biologically active compounds and natural products. Herein, we demonstrate a facile enantioselective intramolecular hydroamination of alkenes for the synthesis of chiral pyrrolidine, piperidine, and indoline moieties, using a manganese (II) chiral aprotic cyclic urea catalyst. The cyclic ligand hinders the inversion of the N atom of the urea and effectively discriminate between the enantiomers of substrates. High-resolution mass spectrometry, deuterium labeling experiments, and molecular orbital energy analysis clearly reveal the intermediates and mechanism of the transformation. As a key step, oxygen coordination by chiral aprotic urea presents a robust control over the asymmetric intra-HA reaction through the involvement of a convergent assembly of two vital intermediates (Mn-N and C-Mn-Br), providing access to chiral cyclic amine systems in high yields with excellent enantioselectivity. Nitrogen-containing rings containing chiral carbon centers are a staple of bioactive molecules and natural products of interest, and synthetic methodologies for their development are a continual focus of organic chemists. Here, the authors disclose a protocol for the synthesis of enantioenriched saturated azacycles, via intramolecular hydroamination of alkenes, using a chiral cyclic urea ligand with manganese. [ABSTRACT FROM AUTHOR]

Nucleic acids have the ability to generate advanced nanostructures in a controlled manner and can interact with target sequences or molecules with high affinity and selectivity. For this reason, they have applications in a variety of nanotechnology applications, from highly specific sensors to smart nanomachines and even in other applications such as enantioselective catalysis or drug delivery systems. However, a common disadvantage is the use of water as the ubiquitous solvent. The use of nucleic acids in non-aqueous solvents offers the opportunity to create a completely new toolbox with unprecedented degrees of freedom. Ionic liquids (ILs) and deep eutectic solvents (DESs) are the most promising alternative solvents due to their unique electrolyte and solvent roles, as well as their ability to maintain the stability and functionality of nucleic acids. This review aims to be a comprehensive, critical, and accessible evaluation of how much this goal has been achieved and what are the most critical parameters for accomplishing a breakthrough. [ABSTRACT FROM AUTHOR]

Atropisomers hold significant fascination, not only for their prevalence in natural compounds but also for their biological importance and wide‐ranging applications as chiral materials, ligands, and organocatalysts. While biaryl and heterobiaryl atropisomers are commonly studied, the enantioselective synthesis of less abundant heteroatom‐linked non‐biaryl atropisomers presents a formidable challenge in modern organic synthesis. Unlike classical atropisomers, these molecules allow rotation around two bonds, resulting in low barriers to enantiomerization through concerted bond rotations. In recent years the discovery of new configurationally stable rare non‐biaryl scaffolds such as aryl amines, aryl ethers and aryl sulfones as well as innovative methodologies to control their configuration have been disclosed in the literature and constitute the topic of this minireview. [ABSTRACT FROM AUTHOR]

Consecutive photoinduced electron transfer (ConPET) is a powerful and atom‐economical protocol to overcome the limitations of the intrinsic redox potential of visible light‐absorbing photosensitizers, thereby considerably improving the substrate and reaction types. Likely because such an exothermic single‐electron transfer (SET) process usually does not require the aid of chiral catalysts, resulting in an inevitable racemic background reaction, notably, no enantioselective manifolds have been reported. Herein, we report on the viability of cooperative ConPET and chiral hydrogen‐bonding catalysis for the [3+2] photocycloaddition of cyclopropyl ketones with vinylazaarenes. In addition to enabling the first use of olefins that preferentially interact with chiral catalysts, this catalysis platform paves the way for the efficient synthesis of pharmaceutically and synthetically important cyclopentyl ketones functionalized by azaarenes with high yields, ees and dr. The robust capacity of the method can be further highlighted by the low loading of the chiral catalyst (1.0 mol %), the good compatibility of both 2‐azaarene and 3‐pyridine‐based olefins, and the successful concurrent construction of three stereocenters on cyclopentane rings involving an elusive but important all‐carbon quaternary. [ABSTRACT FROM AUTHOR]

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

The asymmetric [3+2] cycloaddition of azomethine ylides generated from the corresponding imino ester-to-trans-β-nitrostyrene catalysis by chiral aziridine-containing phosphines and phosphine oxides is described. Of the sixteen stereoisomers that could be formed as a result of the title reaction, three were formed, two of which were obtained in an enantiomerically enriched or pure form, and one in a racemic form. One of the products underwent epimerization under basic reaction conditions. [ABSTRACT FROM AUTHOR]

In this minireview we survey the challenges and strategies in gold redox catalysis. Gold's reluctance to oxidative addition reactions due to its high redox potential limits its applicability. Initial attempts to overcome this problem focused on the use of sacrificial external oxidants in stoichiometric amounts to bring Au(I) compounds to Au(III) reactive species. Recently, innovative approaches focused on employing hemilabile ligands, which are capable of coordinating to Au(I) and stabilizing square‐planar Au(III) intermediates, thus facilitating oxidative addition steps and enabling oxidant‐free catalysis. Notable examples include the use of the (P^N) bidendate MeDalphos ligand to achieve various cross‐coupling reactions via oxidative addition Au(I)/Au(III). Importantly, hemilabile ligand‐enabled catalysis allows merging oxidative addition with π‐activation, such as oxy‐ and aminoarylation of alkenols and alkenamines using organohalides, expanding gold's versatility in C−C and C‐heteroatom bond formations and unprecedented cyclizations. Moreover, recent advancements in enantioselective catalysis using chiral hemilabile (P^N) ligands are also surveyed. Strikingly, versatile bidentate (C^N) hemilabile ligands as competitors of MeDalphos have appeared recently, by designing scaffolds where phosphine groups are substituted by N‐heterocyclic or mesoionic carbenes. Overall, these approaches highlight the evolving landscape of gold redox catalysis and its tremendous potential in a broad scope of transformations. [ABSTRACT FROM AUTHOR]

In the quest for the more rapid and eco‐compatible preparation of complex molecules from widely available ones, borrowing hydrogen is one of the most elegant manners to directly functionalize alcohols. Such catalytic cycles reduce the synthetic cost, and avoid waste and additional steps associated with adjusting the redox state for the functionalization of carbon chains. In this field, the last ten years have seen the development of general strategies to control the absolute stereochemistry of the created molecules. This enantiocontrol can arise from the three distinct steps of the catalytic cycle, namely the initial dehydrogenation, carbonyl functionalization or final hydrogen back‐transfer. This review presents the different enantioselective approaches developed according to these principles and highlights the great potential of these transformations, the current limitations and future challenges. [ABSTRACT FROM AUTHOR]

The synthesis of chiral α-azaheteroaryl oxiranes via enantioselective catalysis is a formidable challenge due to the required complex stereoselectivity and diverse N-heterocyclic structures. These compounds play a crucial role in developing bioactive molecules, where precise chirality significantly influences biological activity. Here we show that using chiral phosphoric acid as a catalyst, our method efficiently addresses these challenges. This technique not only achieves high enantio- and diastereoselectivity but also demonstrates superior chemo- and stereocontrol during the epoxidation of alkenyl aza-heteroarenes. Our approach leverages a synergistic blend of electrostatic and hydrogen-bonding interactions, enabling the effective activation of both substrates and hydrogen peroxide. The resulting chiral oxiranes exhibit enhanced diversity and functionality, aiding the construction of complex chiral azaaryl compounds with contiguous stereocenters. Kinetic and density functional theory studies elucidate the mechanism, highlighting chiral phosphoric acid's pivotal role in this intricate enantioselective process. Chiral azaarenes hold critical importance in pharmaceutical research due to their significant impact on drug efficacy and selectivity. Herein, the authors report the synthesis of chiral α-azaheteroaryl oxiranes via catalytic enantioselective epoxidation of alkenyl aza-heteroarenes using chiral phosphoric acid and hydrogen peroxide. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chiral branched AgAuPt nanoparticles are prepared for enantioselective catalytic. • Chiral catalyst with related CPL irradiation exhibits enhanced HER performance. • Catalysts generate heat and increase catalytic ability via continuous irradiation. • The proposed mechanism is supported by DFT calculation results. Chiral Plasmonic nanomaterials have gradually illustrated intriguing circularly polarized light (CPL)-dependent properties in photocatalysis due to their unique chiral optical activity. However, the connection between chiral characteristics and catalytic performance of these materials in cooperative systems is rarely reported and remains a challenge task. In this work, branched AgAuPt nanoparticles induced by L / d -cysteine (Cys) with strong and perfectly symmetric circular dichroism (CD) signals are synthesized. Chiral branched AgAuPt nanoparticles firstly exhibit superior typical electrocatalytic performance. In the photoelectrocatalytic system, chiral branched AgAuPt nanoparticles demonstrate selective catalytic water splitting performance. Specifically, chiral branched AgAuPt with related CPL irradiation exhibits enhanced acidic hydrogen evolution reaction (HER) performance. Under the continuous irradiation of related CPL, the chiral catalyst generates more heat, which further increases the catalytic activity. This contribution of heat is supported by density functional theory (DFT) calculation results. The changes in chiroptical activity during this process are recorded by variable temperature CD spectra. This work provides a novel paradigm for designing chiral catalysis systems and emphasizes the profound promise of chiral plasmonic nanomaterials as chiral catalysts. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Phthalides serve as core structures pervasive in a wide array of natural products and drug molecules, which display a diverse array of biological activities. We report herein a highly efficient dynamic kinetic resolution of 3‐hydroxyphthalides by chiral isothioureas (ITUs) catalyzed asymmetric acylation, facilitating the effective synthesis of a variety of chiral phthalidyl esters with good yields and enantioselectivities. Notably, this reaction features mild reaction conditions, expansive substrate scope as well as good functional group compatibility. In addition, the practicality of this method is underscored by the large‐scale synthesis, reduced catalyst loading experiment and the synthesis of the chiral phthalidyl ester prodrug. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The implementation of divergent protein engineering on the natural transaminase Vf‐ω‐TA led to the development of two effective mutants (M2 and M8), enabling the enzymatic synthesis of chiral amine precursors of Rivastigmine and Apremilast, respectively. The evolution of the enzymes was guided by crystal structures and a focused mutagenesis strategy, allowing them to effectively address the challenging ketone substrates with significant steric hindrance. Under the optimized reaction parameters, transamination proceeded smoothly in good conversions and with perfect stereochemical control (> 99% ee). These processes utilize inexpensive α‐methylbenzylamine as an amine donor and avoid the continuous acetone removal and costly LDH/GDH/NADH systems. [ABSTRACT FROM AUTHOR]

Due to the innate highly reactive properties and short life‐time, organic free radicals can often serve as promoters or intermediates to engage in various radical transformations, which are often otherwise difficult to access by ionic pathway‐based mechanisms. With the evolvement of radical chemistry, chiral radical catalyzed‐transformations have recently emerged as an attractive and robust platform for synthesis of chiral molecules of interest. Herein, we highlight several creative and strategic advances in chiral radical catalyst design, cyclization reaction achievements, and future challenges. Key Scientists: In the 1980s, some pioneering studies by Feldman and Oshima revealed that the thiyl radical could catalyze cyclization of vinylcyclopropane with alkenes, providing access to racemic cyclopentanes. In 1996, Brian P. Roberts reported an interesting enantioselective hydrosilylation of prochiral alkenes by using thioglucose‐derived chiral thiyl radical catalysts. Since then, chiral radical catalysis has become an emerging and promising catalytic strategy in organic synthesis. However, this field has not been extensively explored further until the Maruoka group in 2014 achieved the asymmetric C—C bond formation by employing a newly designed indanol core‐based chiral thiyl radical catalyst. In this protocol, an enantioselective radical cyclization of vinylcyclopropanes with electron‐rich alkenes was developed. In 2020, Chen and Xiao disclosed a nitrogen radical‐catalyzed version of this reaction. Later, this strategy was further expanded to metalloradical catalyzed asymmetric radical cascade cyclization reactions by Zhang in 2021. Later on, Wang, Fu and Zhang et al. described a novel class of boryl radical‐catalyzed asymmetric radical cycloisomerization reactions, further showcasing enormous synthetic potential of chiral radical catalysis. This Emerging Topic has focused on asymmetric radical cyclization reactions involving diverse chiral radical catalysts. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The implementation of divergent protein engineering on the natural transaminase Vf‐ω‐TA led to the development of two effective mutants (M2 and M8), enabling the enzymatic synthesis of chiral amine precursors of Rivastigmine and Apremilast, respectively. The evolution of the enzymes was guided by crystal structures and a focused mutagenesis strategy, allowing them to effectively address the challenging ketone substrates with significant steric hindrance. Under the optimized reaction parameters, transamination proceeded smoothly in good conversions and with perfect stereochemical control (> 99% ee). These processes utilize inexpensive α‐methylbenzylamine as an amine donor and avoid the continuous acetone removal and costly LDH/GDH/NADH systems. [ABSTRACT FROM AUTHOR]

The new chiral ligands I–III based on derivatives of imidazolidin-4-one were synthesised and characterised. The catalytic activity and enantioselectivity of their corresponding copper(II) complexes were studied in asymmetric Henry reactions. It was found that the enantioselectivity of these catalysts is overall very high and depends on the relative configuration of the ligand used; cis-configuration of ligand affords the nitroaldols with major enantiomer S- (up to 97% ee), whereas the application of ligands with trans-configuration led to nitroaldols with major R-enantiomer (up to 96% ee). The “proline-type” ligand IV was also tested in asymmetric aldol reactions. Under the optimised reaction conditions, aldol products with enantioselectivities of up to 91% ee were obtained.

Non‐directed regioselective activation of bis(boronic esters), followed by functionalization, is reported. A bulky activator is shown to selectively activate the less hindered boronic ester enabling it to undergo stereospecific cross‐coupling to a variety of electrophiles. This steric‐based regioselectivity provides a simple and efficient method to prepare highly functionalized, enantiomerically enriched products starting from simple alkenes. [ABSTRACT FROM AUTHOR]

Chiral nanomaterials with unique chiral configurations and biocompatible ligands have been booming over the past decade for their interesting chiroptical effect, unique catalytical activity, and related bioapplications. The catalytic activity and selectivity of chiral nanomaterials have emerged as important topics, that can be potentially controlled and optimized by the rational biochemical design of nanomaterials. In this review, chiral nanomaterials synthesis, composition, and catalytic performances of different biohybrid chiral nanomaterials are discussed. The construction of chiral nanomaterials with multiscale chiral geometries along with the underlying principles for enhancing chiroptical responses are highlighted. Various biochemical approaches to regulate the selectivity and catalytic activity of chiral nanomaterials for biocatalysis are also summarized. Furthermore, attention is paid to specific chiral ligands, materials compositions, structure characteristics, and so on for introducing selective catalytic activities of representative chiral nanomaterials, with emphasis on substrates including small molecules, biological macromolecule, and in‐site catalysis in living systems. Promising progress has also been emphasized in chiral nanomaterials featuring structural versatility and improved chiral responses that gave rise to unprecedented chances to utilize light for biocatalytic applications. In summary, the challenges, future trends, and prospects associated with chiral nanomaterials for catalysis are comprehensively proposed. [ABSTRACT FROM AUTHOR]

This article discusses the development of a novel immobilization strategy for pyridine-oxazoline (PyOx) ligands on polymeric resins. The immobilized PyOx ligands were evaluated in palladium-catalyzed heterogeneous Heck-Matsuda reactions for the desymmetrization of 3-cyclopenten-1-ol. The results showed that the immobilized ligands achieved comparable enantioselectivity to their homogeneous counterparts, but there was a decline in efficiency with each cycle of catalyst reuse. This study highlights the potential of using supported ligands in asymmetric catalysis and suggests future research to enhance catalyst stability during recycling. [Extracted from the article]

A novel enantioselective Tsuji–Trost‐type cross coupling reaction between gem‐difluorinated cyclopropanes and N‐unprotected amino acid esters enabled by synergistic Pd/Ni/chiral aldehyde catalysis is presented herein. This transformation streamlined the diversity‐oriented synthesis (DOS) of optically active α‐quaternary α‐amino acid esters bearing a linear 2‐fluoroallylic motif, which served as an appealing platform for the construction of other valuable enantioenriched compounds. The key intermediates were confirmed by HRMS detection, while DFT calculations revealed that the excellent enantioselectivity was attributed to the stabilizing non‐covalent interactions between the Pd(II)‐π‐fluoroallyl species and the Ni(II)‐Schiff base complex. [ABSTRACT FROM AUTHOR]

The field of asymmetric catalysis is rapidly developing and the chiral ligands play a key role in enantioselective transition‐metal catalysis. The electron‐rich chiral N‐heterocyclic carbenes (NHCs) have established themselves as a popular class of stereodirecting ancillary ligands to catalyze enantioselective organic transformations in more efficient ways. Several novel transition‐metal complexes in combination with tailored ligand design have emerged during last few decades in asymmetric catalysis. The tailor‐made NHCs can easily be accessed due to the modular synthesis of their parent azolium salt precursors. Their donor capability and the molecular shape can easily be tuned by changing substituent at N‐atom or by changing the cyclic backbone framework. This review article aims to describe the recent advances in this rapidly evolving research area of enantioselective catalysis using well‐defined transition‐metal complexes possessing chiral NHC donor ligands. [ABSTRACT FROM AUTHOR]

Herein, an enantioselective desymmetrization of cyclic keto sulfonium salts through enantioselective deprotonation/ring opening process by anion-binding catalysis is presented. We report a squaramide/HCO3- complex as catalytic active species which is able to stereo-differentiate two enantiomeric protons, triggering the ring opening event taking advantage of the great tendency of sulfonium salts to act as leaving groups. Thus, this desymmetrization methodology give rise to β-methylsulfenylated sulfa-Michael addition type products with excellent yields and very good enantioselectivities. The bifunctional organocatalyst has been demonstrated to be capable of activating simultaneously the base and the keto sulfonium salt by DFT calculations and experimental proofs. Although anion-binding processes are well-known for their crucial role in molecular recognition, this type of phenomenon has only recently been utilized for catalysis. Here, the authors present an enantioselective desymmetrization of cyclic keto sulfonium salts through enantioselective deprotonation/ring opening process by anion-binding catalysis. [ABSTRACT FROM AUTHOR]

Cyclic β,β‐difluoro‐carbonyl compounds have a venerable history as drug discovery leads, but limitations in the synthesis arsenal continue to impede chemical space exploration. This challenge is particularly acute in the arena of fluorinated medium rings where installing the difluoromethylene unit subtly alters the ring conformation by expanding the internal angle (∠C−CF2−C>∠C−CH2−C): this provides a handle to modulate physicochemistry (e.g. pKa). To reconcile this disparity, a highly modular ring expansion has been devised that leverages simple α,β‐unsaturated esters and amides, and processes them to one‐carbon homologated rings with concomitant geminal difluorination (6 to 10 membered rings, up to 95 % yield). This process is a rare example of the formal difluorination of an internal alkene and is enabled by sequential I(III)‐enabled O‐activation. Validation of enantioselective catalysis in the generation of unprecedented medium ring scaffolds is reported (up to 93 : 7 e.r.) together with X‐ray structural analyses and product derivatization. [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]

Asymmetric catalysis stands at the forefront of modern chemistry, serving as a cornerstone for the efficient creation of enantiopure chiral molecules characterized by their high selectivity. In this review, we delve into the realm of asymmetric catalytic reactions, which spans various methodologies, each contributing to the broader landscape of the enantioselective synthesis of chiral molecules. Transition metals play a central role as catalysts for a wide range of transformations with chiral ligands such as phosphines, N-heterocyclic carbenes (NHCs), etc., facilitating the formation of chiral C-C and C-X bonds, enabling precise control over stereochemistry. Enantioselective photocatalytic reactions leverage the power of light as a driving force for the synthesis of chiral molecules. Asymmetric electrocatalysis has emerged as a sustainable approach, being both atom-efficient and environmentally friendly, while offering a versatile toolkit for enantioselective reductions and oxidations. Biocatalysis relies on nature's most efficient catalysts, i.e., enzymes, to provide exquisite selectivity, as well as a high tolerance for diverse functional groups under mild conditions. Thus, enzymatic optical resolution, kinetic resolution and dynamic kinetic resolution have revolutionized the production of enantiopure compounds. Enantioselective organocatalysis uses metal-free organocatalysts, consisting of modular chiral phosphorus, sulfur and nitrogen components, facilitating remarkably efficient and diverse enantioselective transformations. Additionally, unlocking traditionally unreactive C-H bonds through selective functionalization has expanded the arsenal of catalytic asymmetric synthesis, enabling the efficient and atom-economical construction of enantiopure chiral molecules. Incorporating flow chemistry into asymmetric catalysis has been transformative, as continuous flow systems provide precise control over reaction conditions, enhancing the efficiency and facilitating optimization. Researchers are increasingly adopting hybrid approaches that combine multiple strategies synergistically to tackle complex synthetic challenges. This convergence holds great promise, propelling the field of asymmetric catalysis forward and facilitating the efficient construction of complex molecules in enantiopure form. As these methodologies evolve and complement one another, they push the boundaries of what can be accomplished in catalytic asymmetric synthesis, leading to the discovery of novel, highly selective transformations which may lead to groundbreaking applications across various industries. [ABSTRACT FROM AUTHOR]

Amino acid-derived quaternary ammonium salts were successfully applied in the asymmetric aza-Henry reaction of nitromethane to N-Boc trifluoromethyl ketimines. a-Trifluoromethyl p-nitroamines were synthesized in good to excellent yields with moderate to good enantioselectivities. This reaction is distinguished by its mild conditions, low catalyst loading (1 mol%), and catalytic base. It also proceeded on a gram scale without loss of enantioselectivity. The products were transformed to a series of adamantane- type compounds containing chiral trifluoromethylamine fragments. The potent anticancer activities of these compounds against liver cancer HepG2 and melanoma B16F10 were evaluated. Six promising compounds with notable efficacy have potential for further development. [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]

The synthesis of chiral succinimides bearing all‐carbon quaternary stereocenters at the C3 position is important, but remains challenging. The present work demonstrates conjugate additions with catalysis by a chiral 1,10‐phenanthroline‐Pd complex (L1‐PdCl2) that exhibit complete regioselectivity with a high degree of enantioselectivity. These reactions afford chiral 3,3‐disubstituted succinimides having all‐carbon quaternary stereocenters with 40–99% ee. Importantly, chiral 3,3‐diaryl succinimides could also be obtained in 35–98% yields and 40–99% ee. Moreover, the present L1‐PdCl2‐catalyzed asymmetric conjugate addition could be performed on the gram scale and was also used to introduce such stereocenters into bioactive molecules. [ABSTRACT FROM AUTHOR]

Recently, chiral metal‐organic coordination materials have emerged as promising candidates for a wide range of applications in chiroptoelectronics, chiral catalysis, and information encryption, etc. Notably, the chiroptical effect of coordination chromophores makes them appealing for applications such as photodetectors, OLEDs, 3D displays, and bioimaging. The direct synthesis of chiral coordination materials using chiral organic ligands or complexes with metal‐centered chirality is very often tedious and costly. In the case of ionic coordination materials, the combination of chiral anions with cationic, achiral coordination compounds through noncovalent interactions may endow molecular materials with desirable chiroptical properties. The use of such a simple chiral strategy has been proven effective in inducing promising circular dichroism and/or circularly polarized luminescence signals. This concept article mainly delves into the latest advances in exploring the efficacy of such a chiral anion strategy for transforming achiral coordination materials into chromophores with superb photo‐ or electro‐chiroptical properties. In particular, ionic small‐molecular metal complexes, metal clusters, coordination supramolecular assemblies, and metal‐organic frameworks containing chiral anions are discussed. A perspective on the future opportunities on the preparation of chiroptical materials with the chiral anion strategy is also presented. [ABSTRACT FROM AUTHOR]

Strong light‐matter interaction is emerging as an exciting tool for controlling chemical reactions. Here, we demonstrate an L‐proline‐catalyzed direct asymmetric Aldol reaction under vibrational strong coupling. Both the reactants (4‐nitrobenzaldehyde and acetone) carbonyl bands are coupled to an infrared photon and react in the presence of L‐proline. The reaction mixture is eluted from the cavity, and the conversion yields and enantiomeric excess are quantified using NMR and chiral HPLC. The conversion yields increase by up to 90 % in ON‐resonance conditions. Interestingly, a large increase in the conversion yield does not affect the enantiomeric excess. Further control experiments were carried out by varying the temperature, and we propose that the rate‐limiting step may not be the deciding factor in enantioselectivity. Whereas the formation of the enamine intermediate is modified by cavity coupling experiments. For this class of enantioselective reactions, strong coupling does not change the enantiomeric excess, possibly due to the large energy difference in chiral transition states. Strong coupling can boost the formation of enamine intermediate, thereby favouring the product yield. This gives more hope to test polaritonic chemistry based on enantioselective reactions in which the branching ratios can be controlled. [ABSTRACT FROM AUTHOR]

Steric hindrance in Lewis acid (LA) and Lewis base (LB) obstruct the Lewis acid–base adduct formation, and the pair was termed as frustrated Lewis pair (FLP). In the past 16 years, the field of enantioselective catalysis by chiral FLPs has been slowly growing. It was shown that chiral LAs are significant as they are involved in the hydrogen transfer (HT) step to the imine, resulting in enantioselectivity. After H2 activation, the borohydride can exist in a number of plausible conformations and their stability is governed by the presence of noncovalent interaction through C–H····π and π····π interactions. However, LBs are not ideal for asymmetric induction as they compete with the imine substrate as a counter LB. Further, the proton transfer from chiral LB to the imine does not induce any chirality as chirality develops in the HT step. However, intramolecular FLPs with chiral scaffold are very efficient as they possess an optimum distance between LA and LB, which facilitates the H2 activation but precludes the adduct formation of the small molecules substrate with the LA component. This mini‐review summarizes computational investigation involving chiral LA and LB, and discusses intramolecular FLPs in the enantioselective catalysis. [ABSTRACT FROM AUTHOR]

Core-shell structured magnetic wrinkled organosilica-based metal-enzyme integrated catalysts were synthesized, and their catalytic performances were studied in the chemoenzymatic dynamic kinetic resolution of chiral amines in an organic solvent, as well as in the chemoenzymatic synthesis of chiral alcohols in water. Structureperformance studies revealed the important influence of their tunable structure and composition on the optimization of activity, stability, and recyclability in chemoenzymatic catalysis. [ABSTRACT FROM AUTHOR]

Heterogeneous asymmetric catalysis is an important strategy for the industrial production of chiral compounds. Herein, we reported a polymer-bound Xu-Phos-derived palladium catalyst that shows good performance in heterogeneous asymmetric reductive Heck reaction of allyl aryl ethers. This heterogeneous catalyst was easily prepared by efficient immobilization of the sulfonamide phosphine ligand (Xu-Phos) in the cross-linked polystyrene via copolymerization, and exhibits similar catalytic activity and enantioselectivity to that of the homogeneous catalyst. Moreover, the heterogeneous catalyst system is proved to be easily recovered and reused several times without losing catalytic activity obviously. [ABSTRACT FROM AUTHOR]

Chemical Communications is a journal published by The Royal Society of Chemistry, which is a leading chemistry community. The journal contains various articles on topics such as heavy metal ion detection, improving photovoltaic performance, and synthesis of different compounds. The latest issue includes articles on ring expansion of spirocyclopropanes, access to polythioesters, and CO2 cycloaddition. The journal aims to provide a platform for research and advancements in the field of chemistry. [Extracted from the article]

L / D -Phenylglycine amphiphiles and metal ions with peroxidase-like activity self-assembled into chiral nanoribbons, which act as efficient chiral supramolecular nanozymes for catalyzing the 3,4-dihydroxy- L / D -phenylalanine (L / D -DOPA) oxidation reactions. The catalytic efficiency and enantioselectivity are dominated by the chirality transfer and the synergistic effect between the metal ions and chiral nanoribbons. [ABSTRACT FROM AUTHOR]

Homogenous enantioselective catalysis is nowadays the cornerstone in the manufacturing of enantiopure substances, but its technological implementation suffers from well‐known impediments like the lack of endurable catalysts exhibiting long‐term stability. The catalytically active intermetallic compound Palladium‐Gallium (PdGa), conserving innate bulk chirality on its surfaces, represent a promising system to study asymmetric chemical reactions by heterogeneous catalysis, with prospective relevance for industrial processes. Here, this work investigates the adsorption of 10,10′‐dibromo‐9,9′‐bianthracene (DBBA) on the PdGa:A(1¯1¯1¯$\bar{1}\bar{1}\bar{1}$) Pd3‐terminated surface by means of scanning tunneling microscopy (STM) and spectroscopy (STS). A highly enantioselective adsorption of the molecule evolving into a near 100% enantiomeric excess below room temperature is observed. This exceptionally high enantiomeric excess is attributed to temperature activated conversion of the S to the R chiral conformer. Tip‐induced bond cleavage of the R conformer shows a very high regioselectivity of the DBBA debromination. The experimental results are interpreted by density functional theory atomistic simulations. This work extends the knowledge of chirality transfer onto the enantioselective adsorption of non‐planar molecules and manifests the ensemble effect of PdGa surfaces resulting in robust regioselective debromination. [ABSTRACT FROM AUTHOR]

Relying on ubiquitous alkenes, carboamination reactions enable the difunctionalization of the double bond by the concurrent formation of a C−N and a C−C single bond. In the past years, several groups have reported on elegant strategies for the carboamination of alkenes relying on homogeneous catalysts or enzymes. Herein, we report on an artificial metalloenzyme for the enantioselective carboamination of dihydrofuran. Genetic optimization, combined with a Bayesian optimization of catalytic performance, afforded the disubstituted tetrahydrofuran product in up to 22 TON and 85 % ee. X‐ray analysis of the evolved artificial carboaminase shed light on critical amino acid residues that affect catalytic performance. [ABSTRACT FROM AUTHOR]

Chiral cyclopentadienyl‐rhodium(III) CpxRh(III) catalysis has been demonstrated to be competent for catalyzing highly enantioselective aziridination of challenging unactivated terminal alkenes and nitrene sources. The chiral CpxRh(III) catalysis system exhibited outstanding catalytic performance and wide functional group tolerance, yielding synthetically important and highly valuable chiral aziridines with good to excellent yields and enantioselectivities (up to 99 % yield, 93 % ee). This protocol presents a novel and effective strategy for synthesizing enantioenriched aziridines from simple alkenes. Various transformations were performed on the aziridine products, illustrating the versatility and synthetic potential of this protocol for constructing highly functionalized compounds. [ABSTRACT FROM AUTHOR]

The synthetic control of atropoisomerism along C−N bonds is a major challenge, and methods that allow C−N atroposelective bond formation are rare. This is a problem because each atropoisomer can feature starkly differentiated biological properties. Yet, among the three most practical and applicable classical amination methods available: 1) the Cu‐catalyzed Ullmann–Goldberg reaction, 2) the Pd‐catalyzed Buchwald–Hartwig reaction, and 3) the Cu‐catalyzed Chan–Evans–Lam reaction, none has truly been rendered atroposelective at the newly formed C−N bond. The first ever Chan–Evans–Lam atroposelective amination is herein described with a simple copper catalyst and newly designed PyrOx chiral ligand. This method should find important applications in asymmetric synthesis, in particular for medicinal chemistry. [ABSTRACT FROM AUTHOR]

Tridentate bis(carboxamide) pincers are key ligands used in catalysis, investigational medicinal inorganic compounds, and materials science. This study examined the atropisomerism of a group of bis(carboxamide) pincers with C2 symmetry to elucidate their physical, chemical, and structural behaviour, paving the way for the application of their metal complexes in different fields. One of the five compounds structurally elucidated by X-ray crystallography, 1c, has a pair of intramolecularly constrained isoquinoline ring substituents and crystallized enantiomerically pure in a chiral Sohncke space group. PM6 calculations of the 3-D potential energy surface for the main atropisomerisation reaction coordinate of 1c indicated that the lowest-energy conformer (atropisomer) has the isoquinoline rings canted out-of-plane by almost +30° and −30° relative to the central pyridine ring. The X-ray structure of 1c is located close to this energy minimum. Circular dichroism (CD) spectroscopy on bulk solid samples confirmed the presence of an excess population of one enantiomer (C2-symmetric atropisomer), most notably for compounds 1c, 1e, and 1f. CD spectra could be recorded for all compounds in solution, similarly reflecting an excess population of one atropisomer. The experimental spectra were confirmed by TD-DFT simulations at the CAM-B3LYP/def2-tzvp level of theory. We conclude that the present group of ligands are worthy of further investigation as chelating agents for metal ions with applications in chiral catalysis or biology. [ABSTRACT FROM AUTHOR]