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Core–shell gold–silver cuboidal nanoparticles were produced, with either concave or straight facets. Their incubation with a low concentration of chiral l-glutathione (GSH) biomolecules was found to produce near UV plasmonic extinction and induced circular dichroism (CD) peaks. The effect is sensitive to the silver shell thickness. The GSH molecules were found to cause redistribution of silver in the shell, removing silver atoms from edges/corners and re-depositing them at the nanocuboid facets, probably through some redox and complexation processes between the silver and thiol group of the GSH. Other thiolated chiral biomolecules (and drug molecules) did not show this effect. The emerging near UV surface plasmon resonance is a silver slab resonance, which might also possess some multipolar resonance nature. The concave-shaped nanocuboids exhibited stronger induced plasmonic CD relative to the nanocuboids with straight facets. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we reported a precise de novo synthesis of chiral 3,4‐dihydroquinazoline frameworks via a one‐pot anionic stereogenic‐at‐cobalt(III) complex‐catalyzed enantioselective Ugi‐azide/Pd‐catalyzed cyclization sequence. This powerful protocol involves 5 components and 2 catalytic systems, delivering chiral 3,4‐dihydroquinazolines with excellent enantioselectivities (up to 94% ee). The preliminary antifungal experiments suggest that both Ugi‐adducts and 3,4‐dihydroquinazolines have great potential in inhibiting plant pathogens such as Trichoderma viride and Fusarium graminearum. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we reported a precise de novo synthesis of chiral 3,4‐dihydroquinazoline frameworks via a one‐pot anionic stereogenic‐at‐cobalt(III) complex‐catalyzed enantioselective Ugi‐azide/Pd‐catalyzed cyclization sequence. This powerful protocol involves 5 components and 2 catalytic systems, delivering chiral 3,4‐dihydroquinazolines with excellent enantioselectivities (up to 94% ee). The preliminary antifungal experiments suggest that both Ugi‐adducts and 3,4‐dihydroquinazolines have great potential in inhibiting plant pathogens such as Trichoderma viride and Fusarium graminearum. [ABSTRACT FROM AUTHOR]

Comprehensive Summary An efficient asymmetric [4+2] cyclization of hydroxyphenyl indolinone with azlactone for the synthesis of spirooxindole δ‐lactone has been developed, which realized the first asymmetric reaction of hydroxyphenyl indolinone. A series of intricate structures with congested vicinal quaternary chiral centers were provided in good yields with excellent enantioselectivities via the in situ generated o‐QM from hydroxyphenyl indolinone. [ABSTRACT FROM AUTHOR]

Sulfur‐containing functional groups have garnered considerable attention due to their common occurrence in ligands, pharmaceuticals, and insecticides. Nevertheless, enantioselective synthesis of sulfilimines, particularly diaryl sulfilimines remains a challenging and persistent goal. Herein we report a highly enantio‐ and chemoselective cross–coupling of sulfenamides with aryl diazonium salt to construct diverse S(IV) stereocenters by Pd catalysis. Bisphosphine ligands bearing sulfinamide groups play a crucial role in achieving high reactivity and selectivity. This approach provides a general, modular and divergent framework for quickly synthesizing chiral sulfilimines and sulfoximines that are otherwise challenging to access. In addition, the origins of the high chemoselectivity and enantioselectivity were extensively investigated using density functional theory calculations. [ABSTRACT FROM AUTHOR]

The radical Truce–Smiles rearrangement is a straightforward strategy for incorporating aryl groups into organic molecules for which asymmetric processes remains rare. By employing a readily available and non‐expensive chiral auxiliary, we developed a highly efficient asymmetric photocatalytic acyl and alkyl radical Truce–Smiles rearrangement of α‐substituted acrylamides using tetrabutylammonium decatungstate (TBADT) as a hydrogen atom–transfer photocatalyst, along with aldehydes or C−H containing precursors. The rearranged products exhibited excellent diastereoselectivities (7 : 1 to >98 : 2 d.r.) and chiral auxiliary was easily removed. Mechanistic studies allowed understanding the transformation in which density functional theory (DFT) calculations provided insights into the stereochemistry‐determining step. [ABSTRACT FROM AUTHOR]

Organic‐chemical literature encompasses large numbers of catalysts and reactions they can effect. Many of these examples are published merely to document the catalysts' scope but do not necessarily guarantee that a given catalyst is "optimal"—in terms of yield or enantiomeric excess—for a particular reaction. This paper describes a Machine Learning model that aims to improve such catalyst‐reaction assignments based on the carefully curated literature data. As we show here for the case of asymmetric magnesium catalysis, this model achieves relatively high accuracy and offers out of‐the‐box predictions successfully validated by experiment, e.g. in synthetically demanding asymmetric reductions or Michael additions. [ABSTRACT FROM AUTHOR]

The Petasis reaction is a multicomponent reaction of aldehydes, amines and organoboron reagents and is a useful method for the construction of substituted amines. Despite the significant advancement of the Petasis reaction since its invention in 1993, strategies for asymmetric and non‐directed Petasis reactions remain limited. To date, there are very few catalytic asymmetric Petasis reactions and almost all asymmetric reports employ a chiral auxiliary. Likewise, the aldehyde component often requires a directing group, ultimately limiting the reaction's scope. In this Concept, key methods for asymmetric and non‐directed Petasis reactions are discussed, focusing on how these conceptual advances can be applied to solve long‐standing gaps in the Petasis literature. [ABSTRACT FROM AUTHOR]

Membrane materials that resist nonspecific or specific adsorption are urgently required in widespread practical applications, such as water purification, food processing, and life sciences. In water purification, inevitable membrane fouling not only limits membrane separation performance, leading to a decline in both permeance and selectivity, but also remarkably increases operation requirements, and augments extra maintenance costs and higher energy consumption. In this work, we report a freestanding interfacial polymerization (IP) fabrication strategy for in situ creation of asymmetric block copolymer (BCP) nanofilms with antifouling properties, greatly outperforming the conventional surface post‐modification approaches. The resultant free‐standing asymmetric BCP nanofilms with highly‐dense, highly‐hydrophilic polyethylene glycol (PEG) brushes on one side, can be readily formed via a typical IP process of a well‐defined double‐hydrophilic BCP composed of a highly‐efficient antifouling PEG block and a membrane‐forming multiamine block. The asymmetric BCP nanofilms have been applied for efficient and sustainable natural water purification, demonstrating extraordinary antifouling capabilities accompanied with superior separation performance far beyond commercial polyamide nanofiltration membranes. The antifouling behaviors of asymmetric BCP nanofilms derived from the combined effect of the hydration layer, electrostatic repulsion and steric hindrance were further elucidated by water flux and fouling resistance in combination with all‐atom molecular dynamics (MD) simulation. This work opens up a new avenue for the large‐scale and low‐cost creation of broad‐spectrum, asymmetric membrane materials with diverse functional "defect‐free" surfaces in real‐world applications. [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]

Functionalization of Si‐bound methyl group provides an efficient access to diverse organosilanes. However, the asymmetric construction of silicon‐stereogenic architectures by functionalization of Si‐bound methyl group has not yet been described despite recent significant progress in producing chiral silicon. Herein, we disclosed the enantioselective silylmethyl functionalization involving the aryl to alkyl 1,5‐palladium migration to access diverse naphthalenes possessing an enantioenriched stereogenic silicon center, which are inaccessible before. It is worthy to note that the realization of asymmetric induction at the step of metal migration itself remains challenging. Our study constitutes the first enantioselective aryl to alkyl 1,5‐palladium migration reaction. The key to the success is the discovery and fine‐tuning of the different substituents of α,α,α,α‐tetraaryl‐1,3‐dioxolane‐4,5‐dimethanol (TADDOL)‐based phosphoramidites, which ensure the enantioselectivity and desired reactivity. [ABSTRACT FROM AUTHOR]

The sulfinyl group, as one of the bioisosteres of carbonyl groups, attracts considerable attention in the field of synthetic chemistry. In particular, the asymmetric construction of chiral sulfinyl compounds and their derivatives remains in the early stages of development. Sulfinyl compounds mainly include sulfoxides, sulfinate esters and sulfinamides, according to the different functional groups connected to the sulfur atom. This Review summarizes the fascinating recent progress made over the past decade on the asymmetric synthesis of enantiopure sulfinyl derivatives. 1 Introduction 2 Asymmetric Synthesis of Chiral Sulfoxides 3 Asymmetric Synthesis of Chiral Sulfinate Esters 4 Asymmetric Synthesis of Chiral Sulfinamides 5 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Herein, we present an efficient synthesis method utilizing Bi quantum dots (QDs) as catalysts for the photochemical oxidative coupling of thiols to disulfides under mild conditions. The protocol offers low catalyst loading, simplicity in reaction setup as well as high efficiency. Aromatic thiols and aliphatic thiols are successfully transformed into disulfides with good to quantitative yields, demonstrating tolerance to various substituents and heterocycles. Additionally, the protocol extends to the synthesis of asymmetric disulfides and allows for gram-scale synthesis. An efficient synthesis method utilizing Bi quantum dots (QDs) as catalysts for the photochemical oxidative coupling of thiols to disulfides under mild conditions is reported. The protocol offers low catalyst loading with high efficiency. Symmetric and asymmetric disulfides have been successfully obtained which allows for gram-scale synthesis. [ABSTRACT FROM AUTHOR]

We found that during the chiral co-assembly process, the structural symmetry of achiral Py-based emitters could cause different chiral co-assembly modes, leading to the tunable CPL emission behaviors of the resulting co-assemblies. Most importantly, this kind of chiral co-assembly (R / S -B) 1 -(Py-2) 7 can form highly ordered helical nanofiber through intermolecular layered packing mode, leading to the promoted chiral induction and amplification effects. [Display omitted] The regulation of circularly polarized luminescence (CPL) behavior is of great significance for practical applications. Herein, we deliberately designed three achiral pyrene derivatives (Py-1 , Py-2 , and Py-3) with different butoxy-phenyl substituents and the chiral binaphthyl-based inducer ( R/S -B) with anchored dihedral angle to construct chiral co-assemblies, and explored their induced CPL behaviors. Interestingly, the resulting co-assemblies demonstrate tunable CPL emission behaviors caused by the structural symmetry effect of achiral pyrene-based emitters during the chiral co-assembly process. And in spin-coated films, the dissymmetry factor (g em) values were 9.1 × 10-3 for (R/S- B) 1 -(Py-1) 10 , 5.6 × 10-2 for (R/S- B) 1 -(Py-2) 7 , and 8.6 × 10-4 for (R/S- B) 1 -(Py-3) 1 , respectively. The strongest CPL emission (| g em | = 5.6 × 10-2, λ em = 423 nm, QY = 34.8 %) was detected on (R/S- B) 1 -(Py-2) 7 due to the formation of regular and ordered helical nanofibers through the strong π-π stacking interaction between the R/S- B and the achiral Py-2 emitter. The strategy presented here provides a creative approach for progressively regulating CPL emission behaviors in the chiral co-assembly process. [ABSTRACT FROM AUTHOR]

A new catalytic decarboxylative cyanation and thiocyanation via a synergistic NaI/Cu catalysis is developed. The photoexcited electron donor-acceptor complex by assembly of NaI, R3P, and N-acyloxy-phthalimide ester (NHPI ester) triggers the generation of alkyl radical species, which then engages in Cu-catalyzed radical coupling process. Key to success of this dual catalytic transformation is the reliable charge transfer between I· and Cu(I). This dual catalytic platform can eliminate the use of expensive iridium-based photocatalyst or synthetically elaborate organic dyes. A series of primary, secondary, and tertiary alkyl nitriles and thiocyanates are easily synthesized. Moreover, an asymmetric decarboxylative cyanation by applying a chiral Cu catalyst is also developed to afford chiral nitriles in high enantioselectivity. The mechanistic details and the origin of the high enantioselectivity are further investigated by the mechanistic experiments and the density functional theory calculations. [ABSTRACT FROM AUTHOR]

The self‐assembled cellulose nanocrystal (CNC) film has a left‐handed layered structure, which makes the reflection of right‐handed circularly polarized (CP) light a challenge. Herein, a nematic phase layer is designed and inserted into the chiral organization, to work as a half‐wave retarder and make the ambidextrous CP light reflection. The maximum reflectivity exceeds 80%, which breaks the 50% limitations of single‐direction light reflection and is the current maximum in all the reported CNC‐based films. This “sandwich‐like” structure displays different optical properties on both sides, displayed as the chromatism and the inversion of the circular dichroism signals. The dual CP light reflection and direction‐dependent optical phenomena are reserved in the synthesized circularly polarized luminescence (CPL) film, with the dissymmetry factor (glum) of −0.4245. However, this luminescent intensity and single‐direction emission are not enough in advanced optical systems. This work designs a triple CPL amplification path and develops the handedness inversion strategy, with the glum of −1.0551 and 0.4082. Then, the dual‐directional CPL emission films are designed, where the chiral optics can be switched on‐demand. Finally, the photonic crystal films are applied in the anti‐counterfeit and chiral superstructure induction. [ABSTRACT FROM AUTHOR]

β‐Chiral carboxylic acids and their derivatives are highly valuable structural motifs in the fields of asymmetric synthesis and medicinal chemistry. However, the introduction of a sterically demanding sidechain to the β‐carbon, such as an all‐carbon quaternary center, remains a significant challenge in classical polar processes. Recently, N‐heterocyclic carbene (NHC) mediated coupling reactions involving persistent ketyl radicals have emerged as a promising strategy to assemble highly crowded carbon‐carbon bonds. Nevertheless, achieving enantioselectivity in these reactions remains highly challenging. In this work, we report our recent progress in controlling enantioselectivity for relay coupling of perfluoroalkyl and persistent vinylogous ketyl radicals. We developed a chiral bifunctional NHC‐squaramide catalyst that achieves high facial selectivity in a critical bond‐forming event involving the coupling of a congested tertiary carbon radical and vinylogous ketyl radical. Chiral carboxylates bearing an all‐carbon quaternary center at the β‐position can be prepared in good yield and excellent enantiomeric excess. Results from density functional theory (DFT) calculations and nuclear Overhauser effect (NOE) experiments indicate that the N,N'‐diaryl squaramide motif adopts an unusual syn‐syn conformation, enabling hydrogen bonding interactions with the enolate oxygen, thereby rigidifying the overall conformation of the transition state. [ABSTRACT FROM AUTHOR]

Sulfinamidines are promising aza‐SIV chiral building blocks in asymmetric synthesis and drug discovery. However, no report has documented their enantioselective synthesis. Here we present an enantioselective synthesis of sulfinamidines via electrophilic amination of sulfenamides using an enantiopure N−H oxaziridine. The resulting enantiomerically enriched primary sulfinamidines are configurationally stable at 90 °C in solution and show remarkable stability against organic acids and bases under non‐aqueous conditions. We also demonstrate a one‐pot, three‐component, enantioselective synthesis of sulfinamides using N−H oxaziridine reagents. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed asymmetric 1,n‐remote aminoacetoxylation of cis‐alkenes has been developed using PhI(OAc)2 as an oxidant, providing the acetoxylated lactams with excellent enantioselectivities under mild reaction conditions. The sterically hindered pyridine‐oxazoline (Pyox) L3 with a tert‐butyl group in oxazoline ring and propyl group in C6 position of pyridinyl is vital for the reaction, where the former is good for asymmetric aminopalladation step and the latter for the chain walking process. The enantioenriched lactam products were proven to be good building blocks for the synthesis of azabicycles. [ABSTRACT FROM AUTHOR]

Herein we illustrate a first asymmetric synthesis of medicinally attractive tetrahydro‐1,4‐benzodiazepin‐2‐ones performed under catalytic conditions and one‐pot fashion. The process relies on a sequential Knoevenagel reaction/asymmetric epoxidation/domino ring‐opening cyclization (DROC) using commercially available aldehydes, phenylsulfonylacetonitrile, cumyl hydroperoxide, 2‐(aminomethyl)aniline and a readily available quinine‐derived urea as the catalyst. The heterocycles have been isolated with good regioselectivity, satisfactory to good yield and up to 98 % ee. The protocol proved also to be suitable for the preparation of previously undescribed 1,5‐dihydro‐4,1‐benzoxazepin‐3(2H)‐ones with up to 86 % ee. [ABSTRACT FROM AUTHOR]

Aldolases are powerful C−C bond‐forming enzymes with high stereoselectivity and broad substrate scope in biocatalysis, but their ability to stereoselectively construct tertiary alcohols has not been fully explored. Herein, we demonstrate that vicinal diones and α‐keto esters are electrophiles that can be accepted by both natural and computationally designed aldolases via various catalytic mechanisms. This method allows for the efficient asymmetric synthesis of small molecules with tertiary alcohols, including noncanonical amino acids. This study presents the first types of generic nonnatural substrates of aldolases and reveals new opportunities for the use of aldolases in the synthesis of versatile chiral synthons. [ABSTRACT FROM AUTHOR]

AbstractCompounds containing chiral C–N bonds play a vital role in the composition of biologically active natural products and small pharmaceutical molecules. Therefore, the development of efficient and convenient methods for synthesizing compounds containing chiral C–N bonds is a crucial area of research. Nicotinamide-dependent oxidoreductases (NDOs) emerge as promising biocatalysts for asymmetric synthesis of chiral C–N bonds due to their mild reaction conditions, exceptional stereoselectivity, high atom economy, and environmentally friendly nature. This review aims to present the structural characteristics and catalytic mechanisms of various NDOs, including imine reductases/ketimine reductases, reductive aminases, EneIRED, and amino acid dehydrogenases. Additionally, the review highlights protein engineering strategies employed to modify the stereoselectivity, substrate specificity, and cofactor preference of NDOs. Furthermore, the applications of NDOs in synthesizing essential medicinal chemicals, such as noncanonical amino acids and chiral amine compounds, are extensively examined. Finally, the review outlines future perspectives by addressing challenges and discussing the potential of utilizing NDOs to establish efficient biosynthesis platforms for C–N bond synthesis. In conclusion, NDOs provide an economical, efficient, and environmentally friendly toolbox for asymmetric synthesis of C–N bonds, thus contributing significantly to the field of pharmaceutical chemical development. [ABSTRACT FROM AUTHOR]

A highly effective enantioselective monobenzoylation of 1,3‐diols has been developed for the synthesis of 1,1‐disubstituted tetrahydro‐β‐carbolines. The chemistry has been successfully applied to the asymmetric total synthesis of (+)‐alstrostine G, which also features a cascade Heck/hemiamination reaction enabling facile construction of the pivotal pentacyclic core. [ABSTRACT FROM AUTHOR]

Herein we report the first transition metal‐catalyzed approach to the enantioenriched synthesis of cyclic sulfonimidamides relying on commercially available palladium catalysts and ligands. High‐throughput experimentation (HTE) was employed to identify the optimal catalyst system and solvent. The method is applied to a variety of saturated and unsaturated rings and exhibits the highest selectivity for 2‐substituted allyl electrophiles. The products are further elaborated to complex, tricyclic scaffolds. DFT experiments presented herein highlight the key ligand substrate interactions leading to the high levels of enantioselectivity. [ABSTRACT FROM AUTHOR]

The Pd‐catalysed decarboxylative asymmetric allylic alkylation (DAAA) has been applied to the enantioselective synthesis of sterically hindered benzofuran‐3(2H)‐one‐derived α‐aryl‐β‐keto esters employing the (R,R)‐ANDEN phenyl Trost ligand. A range of substrates were synthesised, employing previously developed aryllead triacetate methodology to install various aryl groups. The resulting α‐aryl‐α‐allyl benzofuran‐3(2H)‐one DAAA products were obtained in moderate to high yields and in enantioselectivities of up to 96 % ee, with the best results observed for substrates containing a di‐ortho‐substitution pattern on the aryl ring as well as naphthyl‐containing substrates. [ABSTRACT FROM AUTHOR]

The direct diastereo‐ and enantioselective Ru(II)‐ catalyzed cyclopropanation reaction of alkenes with ((2‐diazo‐1,1‐difluoroethyl)sulfinyl)benzene was described. The desired enantioenriched PhSO2CF2‐cyclopropanes were obtained in high yields with high diastereo‐ and enantioselectivities in the presence of a chiral ruthenium complex Ru(II)‐Pheox (17–94% yields, >20:1 d.r. and 83:17–98:2 e.r.). The robustness of the approach was showcased and This methodology gave access to chiral 1,2‐trans difluoro‐methylcyclopropanes. [ABSTRACT FROM AUTHOR]

Molecules with chiral boron atoms have been scarcely studied due to limited synthetic access. Herein, we report a new method for their synthesis via asymmetric insertion of arydiazoacetates into the B–H bonds of prochiral carbene–boranes NHC–BH2R. The reaction is catalyzed by the rhodium(I) complex with the chiral diene ligand tBu2-TFB, which can be conveniently prepared by diastereoselective coordination of the racemic diene with (S-Salox)Rh(CO)2. The target boranes were typically obtained in 75–90% yields with 90–95% ee. [ABSTRACT FROM AUTHOR]

ABSTRACT Inspired by the multienzymatic relay catalysis in nature, herein, we reported a pioneering bio‐inspired Cu/Pd bimetallic composite microspheres (Cu/CMC@Pd/C) as a simple and efficient relay catalyst for the homo‐coupling of arylboronic acids. In this composite, Pd/C was encapsulated by Cu(II)‐crosslinking carboxymethyl cellulose (Cu/CMC). Cu/CMC@Pd/C microspheres were easily achieved by adding a mixture solution of Pd/C and carboxymethyl cellulose into a Cu(II) solution through an ion exchange reaction between carboxylate groups of CMC and Cu(II) ions. The morphology and composition of the as‐prepared Cu/CMC@Pd/C microspheres were well characterized using various analytical tools such as FT‐IR, XRD, XPS, SEM, TEM, elemental mapping, EDS, and ICP‐AES. The analysis indicated that the composite microspheres have a porous structure and Pd/C is uniformly distributed within the interior of the composite microspheres. The porous structure facilitates mass transfer of the substrate and increases the contact area of the catalyst, thus improving reaction efficiency. The performance of Cu/CMC@Pd/C microspheres was assessed in the homo‐coupling of arylboronic acid for the synthesis of symmetric biaryl without the need for an aryl halide as a partner. This process mimics a multienzyme catalysis through a relay Cu(I)‐catalyzed halogenation of one portion of arylboronic acid and a Pd(0)‐catalyzed Suzuki–Miyaura cross‐coupling between the in situ generated aryl halide and another portion of arylboronic acid. The results showed that this bio‐inspired Cu/CMC@Pd/C has excellent relay catalytic activity with tolerance of broad functional groups, producing the desired symmetrical biaryls in excellent yields within a short reaction time under mild conditions. Moreover, the catalyst can be easily recovered through simple filtration and still has good catalytic activity after six cycles. Consequently, this innovative pseudo‐homogeneous Cu/Pd relay catalyst emerges as a convenient and efficient alternative for the synthesis of asymmetric biaryls. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium catalysis. This method demonstrates a wide substrate applicability, excellent tolerance for various functional groups, and good enantioselectivities (up to 90% ee). It provides a convenient pathway to produce a diverse range of structurally distinct chiral dihydrocoumarins in good efficiency. [ABSTRACT FROM AUTHOR]

The tea tussock moth is a pest that damages tea leaves, affecting the quality and yield of tea and causing huge economic losses. The efficient asymmetric total synthesis of the sex pheromone of the tea tussock moth was achieved using commercially available starting materials with a 25% overall yield in 11 steps. Moreover, the chiral moiety was introduced by Evans' template and the key C-C bond construction was accomplished through Julia–Kocienski olefination coupling. The synthetic sex pheromone of the tea tussock moth will facilitate the subsequent assessment and implementation of pheromones as environmentally friendly tools for pest management. [ABSTRACT FROM AUTHOR]

An asymmetric synthesis is a favorable approach for obtaining enantiomerically pure substances, but racemic resolution remains an efficient strategy. This study aims to elucidate the chiral resolution of aromatic amino acids and their elution order using glycopeptides as chiral selectors through molecular docking analysis. Chiral separation experiments were conducted using Vancomycin as a chiral additive in the mobile phase (CMPA) at various concentrations, coupled with an achiral amino column as the stationary phase. The Autodock Vina 1.1.2 software was employed to perform molecular docking simulations between each enantiomer (ligand) and Vancomycin (receptor) to evaluate binding affinities, demonstrate enantiomeric resolution feasibility, and elucidate chiral recognition mechanisms. Utilizing Vancomycin as CMPA at a concentration of 1.5 mM enabled the separation of tryptophan enantiomers with a resolution of 3.98 and tyrosine enantiomers with a resolution of 2.97. However, a poor chiral resolution was observed for phenylalanine and phenylglycine. Molecular docking analysis was employed to elucidate the lack of separation and elution order for tryptophan and tyrosine enantiomers. By calculating the binding energy, docking results were found to be in good agreement with experimental findings, providing insights into the underlying mechanisms governing chiral recognition in this system and the interaction sites. This comprehensive approach clarifies the complex relationship between chiral discrimination and molecular architecture, offering valuable information for creating and improving chiral separation protocols. [ABSTRACT FROM AUTHOR]

Five- and six-membered cyclic amide structures with an embedded endocyclic α-aza group (α-aza-lactams) not only represent masked or protected forms of α-amino acids, but also form the core of other medicinally relevant compound families such as (thio)hydantoins and di(tri)ketopiperazines. In recent years, catalytic methods have been discovered to synthesize these molecular scaffolds, particularly those bearing an α-stereogenic tri- or tetrasubstituted carbon center, enantioselectively. The wide variety of methods and catalytic activation strategies that have been successfully applied to this end in a short period of years is notable. This short review covers the most significant, highlighting their differences and complementarities. The methods are organized according to the disconnection approach to the target α-aza-lactam structure, which in most cases is deeply bound to the type of catalysis applied. 1 Introduction 2 Catalyst-Controlled Cα –H Functionalization (Approach a) 3 Decarboxylative α-AAA Reactions (Approach b) 4 Cα –X Substitution Reactions (Approach c) 5 De Novo Synthesis from Acyclic Precursors (Approach d) 6 Hydrogenation of (Addition to) α-Alkyliden-α-aza-lactams (Approach e) 7 Kinetic Resolution and Deracemization (Approach f) 8 Conclusions [ABSTRACT FROM AUTHOR]

An efficient organocatalytic cascade vinylogous Michael‐cyclization to construct the challenging full substituted cyclohexa‐1,3‐dienes has been developed. Catalyzed by the cinchona alkaloids‐derived thiourea VIII at −60 °C, the products were obtained as a single diastereomer with two contiguous stereocenters and more than four different useful functional groups in moderate to good yields and good to excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

The synergistic combination of biocatalysis and photocatalysis is emerging as powerful tool for the development of sustainable and atom‐efficient synthetic concepts facilitating an enormous portfolio of possible reactions which even goes beyond the capabilities found in nature. Here, a cyclic deracemization process is presented tailored for the synthesis of optically pure sulfoxides which are versatile structural motifs in asymmetric synthesis as well as in bioactive compounds. Enantioselective enzyme‐catalyzed reduction of rac‐sulfoxides was combined with a stereo‐unselective photocatalytic oxidation of the corresponding sulfide intermediate. The utilization of the readily accessible and rather inexpensive photocatalyst Eosin Y increases the usability of this synthetic method. To overcome the incompatibility between the photocatalyst Eosin Y and the biocatalytic step, the cyclic deracemization process was performed in a step‐wise fashion via alternated reduction in the darkness and oxidation under illumination. This modular system allowed precise adjustments of reaction parameters yielding the desired sulfoxide targets with up to >99 % ee. Evaluation of the substrate scope including a range of structurally diverse molecules demonstrated its broad applicability. [ABSTRACT FROM AUTHOR]

Thiamine diphosphate (ThDP) dependent carboligases catalyze the formation of carbon‐carbon bonds. These enzymes are prominent biocatalysts for the production of valuable α‐hydroxy carbonyl compounds, which serve as key building blocks in the synthesis of various pharmaceuticals and fine chemicals. Carboligases act in selective manner to afford regio‐ and stereochemically defined products from simple starting materials. This review explores the catalytic prowess of carboligases for synthetic purposes and is aimed at providing a selection tool of enzymes for particular sets of substrates or desired products. The comprehensive overview encompasses structural insights, relationships of the currently known sequence space and practical applications with a focus on recent literature, showcasing carboligases as potent tools for sustainable and efficient synthesis. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Society Reviews. It highlights various articles and reviews that have been published in the journal, covering topics such as colorimetric sensing, zinc-ion dehydration strategies, metal nanowire-based transparent electrodes, sodium layered oxide cathodes, one-pot chemo- and photo-enzymatic cascade processes, functionalized 2D membranes for separations, nucleic acid-based wearable and implantable electrochemical sensors, and catalytic asymmetric synthesis of 1,2-diamines. The journal aims to connect the world with the chemical sciences and reinvest its profits back into the chemistry community. [Extracted from the article]

We describe a full account of our synthetic strategy leading to the first total synthesis of the manzamine alkaloid lissodendoric acid A. These efforts demonstrate that strained cyclic allenes are valuable synthetic building blocks and can be employed efficiently in total synthesis. [ABSTRACT FROM AUTHOR]

This concept article explores the emerging role of atropisomerism in foldamer chemistry, a field focussed on oligomers that adopt well‐defined conformations through non‐covalent interactions. Atropisomerism introduces a novel dimension to foldamer design by restricting rotational freedom around single bonds to dictate molecular shape with precision. Despite the prevalence of atropisomeric bonds in organic synthesis, their application within foldamers remains underexplored. Here, we discuss key developments in both backbone and sidechain atropisomerism, and suggest future directions for atropisomeric foldamers in the context of a recent surge in atropselective synthetic methods. We propose that judicious use of atropisomerism may serve as a transformative tool in the construction of shape‐defined macromolecules. [ABSTRACT FROM AUTHOR]

The synthesis and application of organoselenium compounds have developed rapidly, and chiral organoselenium compounds have become an important intermediate in the field of medicine, materials, organic synthesis. The strategy of developing a green economy is still a challenge in the synthesis of chiral organoselenium compounds with enantioselective properties. This review covers in detail the synthesis of chiral organoselenium compounds from 1979 to 2024 and their application in the fields of asymmetric synthesis and catalysis. [ABSTRACT FROM AUTHOR]

Organic fluorides are widely used in pharmaceuticals, agrochemicals, material sciences, and other fields due to the special physical and chemical properties of fluorine atoms. The synthesis of alkyl fluorinated compounds bearing multiple contiguous stereogenic centers is the most challenging research area in synthetic chemistry and has received extensive attention from chemists. This review summarized the important research progress in the field over the past decade, including asymmetric electrophilic fluorination and the asymmetric elaboration of fluorinated substrates (such as allylic alkylation reactions, hydrofunctionalization reactions, Mannich addition reactions, Michael addition reactions, aldol addition reactions, and miscellaneous reactions), with an emphasis on synthetic methodologies, substrate scopes, and reaction mechanisms. [ABSTRACT FROM AUTHOR]

Malamides (diamide derivatives of malic acid) are prevalent in nature and of significant biological interest, yet only limited synthetic methods to access functionalised enantiopure derivatives have been established to date. Herein, an effective synthetic method to generate this molecular class is developed through in situ formation of spirocyclic β-lactone-oxindoles (employing a known enantioselective isothiourea-catalysed formal [2+2] cycloaddition of C(1)-ammonium enolates and isatin derivatives) followed by a subsequent dual ring-opening protocol (of the β-lactone and oxindole) with amine nucleophiles. The application of this protocol is demonstrated across twelve examples to give densely functionalised malamide derivatives with high enantio- and diastereo-selectivity (up to >95:5 dr and >99:1 er). [ABSTRACT FROM AUTHOR]

We report the facile synthesis of asymmetric perylene diimides (asym−PDIs) using readily available reagents, demonstrating their distinct photoluminescent properties. In CHCl3, asym−PDIs exhibit higher solubility compared to traditional perylene dyes, of which solubilities can be varied by substituent selections. Among them, UV‐vis absorption spectra of CPE in CHCl3 solution displayed no aggregate peaks in the ground state, maintaining high photoluminescent quantum yields. Also, CPE can be readily dispersed into poly(methyl methacrylate) PMMA (CPE−PMMA), forming thin films without aggregate formation. Importantly, the emission color of CPE−PMMA thin films significantly changes with the addition of polycyclic aromatic hydrocarbons (PAHs). These color changes should be strongly correlated with the HOMO level of the added PAHs. [ABSTRACT FROM AUTHOR]

In this article, chiral covalent organic framework core‐shell composite CCOF‐TpPa‐Py@SiO2 was facilely synthesized by induction at room temperature. The CCOF‐TpPa‐Py@SiO2 core‐shell composite was used as a chiral stationary phase for the separation of the racemates by high‐performance liquid chromatography, which exhibits good separation performance for chiral compounds including ketones, alcohols, esters, epoxides, carboxylic acids, amides, and amines. The effects of analyte injection mass on the enantioseparation were studied. The reproducibility and stability of the CCOF‐TpPa‐Py@SiO2 chiral column were explored. The intra‐day (n = 5), inter‐day (n = 5), and inter‐column (n = 3) relative standard deviations for the migration times and resolution of benzoin were 0.32%–0.54%, 0.45%–0.61%, and 1.21%–1.53%, respectively. In addition, the chiral separation ability of the CCOF‐TpPa‐Py@SiO2 chiral column (column A) was compared with that of the MDI‐β‐CD‐Modified COF@SiO2 (column B) as well as a commercial chiral column (Chiralpak AD‐H). The chiral recognition ability of column A is complementary to that of column B and AD‐H column. The resolution mechanism of CCOF‐TpPa‐Py@SiO2 stationary phase towards chiral analyte was explored. Hence, the synthesis of CCOF‐TpPa‐Py@SiO2 core‐shell composite by induction at room temperature as chiral stationary phases for chromatographic separation has important research potential and application prospects. [ABSTRACT FROM AUTHOR]

A novel CCOF core–shell composite material (S)-DTP-COF@SiO2 was prepared via asymmetric catalytic and in situ growth strategy. The prepared (S)-DTP-COF@SiO2 was utilized as separation medium for HPLC enantioseparation using normal-phase and reversed-phase chromatographic modes, which displays excellent chiral separation performance for alcohols, esters, ketones, and epoxides, etc. Compared with chiral commercial chromatographic columns (Chiralpak AD-H and Chiralcel OD-H columns) and some previously reported chiral CCOF@SiO2 (CC-MP CCTF@SiO2 and MDI-β-CD-modified COF@SiO2)-packed columns, there are 4, 3, 13, and 15 tested racemic compounds that could not be resolved on the Chiralpak AD-H column, Chiralcel OD-H column, CC-MP CCTF@SiO2 column, and MDI-β-CD-modified COF@SiO2 column, respectively, which indicates that the resolution effect of (S)-DTP-COF@SiO2-packed column can be complementary to the other ones. The effects of the analyte mass, column temperature, and mobile phase composition on the enantiomeric separation were investigated. The chiral column exhibits good reproducibility after multiple consecutive injections. The RSDs (n = 5) of the peak area and retention time were less than 1.5% for repetitive separation of 2-methoxy-2-phenylethanol and 1-phenyl-1-pentanol. The chiral core–shell composite (S)-DTP-COF@SiO2 exhibited good enantiomeric separation performance, which not only demonstrates its potential as a novel CSP material in HPLC but also expands the range of applications for chiral COFs. [ABSTRACT FROM AUTHOR]

A recent interest attaches to the derivatives of the (2‐benzylsulfinyl)benzoic acid as inhibitors of human carbonic anhydrases (hCAs), an action that can be applied in innovative therapies. A set of crystal structures of six sulfides and six enantiopure sulfoxides related to this scaffold, taken from the literature, or derived from the work on the asymmetric synthesis of sulfinyl compounds, is investigated. The lattice energies of these structures are estimated by means of the Crystal Explorer 21 program. The weak interactions building up the crystal structures are identified, and their contributions are analyzed in comparison with the calculated lattice energies. The most stable conformations in the solid phase are identified. It is worth observing that the sulfides of the scaffold under investigation behave almost in the same manner; on the other hand, the presence of the sulfinyl group of the sulfoxides adds complexity, that shall be taken into account in future docking calculations of these molecules with the hCAs enzymes. [ABSTRACT FROM AUTHOR]

Piperazines constitute an important structural feature of many pharmaceuticals. For the discovery of new drugs, the ability to modify the lead compound's structure is crucial. Herein, we provide an efficient method for the synthesis of chiral 2,3,5-trisubstituted piperazine structures. Our route enables the synthesis of several novel chiral aryl aziridinyl ketones that could be converted into aziridine-fused bicyclic imines. The reduction of these imines and the nucleophilic ring-opening reaction of the aziridine ring allowed us to synthesize highly functionalized piperazine derivatives. [ABSTRACT FROM AUTHOR]

Chirality is one of the fundamental properties of molecules traditionally constructed from atoms. Here, we report for the first time the successful construction of asymmetric chiral structures utilizing highly symmetric endohedral metallofullerene superatoms based on their own bonding properties. Specifically, stable mirror‐symmetric sinister and rectus structures are obtained by selecting a superatom capable of forming four chemical bonds as the chiral center. Further analysis shows that the chiral vibration frequency of superatomic assemblies can be as low as a few wavenumbers, which greatly expands the range of chiral spectra compared to atom‐based molecules. We term this type of chirality based on superatoms as "superatomic‐based chirality". It is anticipated that this work will significantly expand the variety of chiral structures at the atomic level. [ABSTRACT FROM AUTHOR]

Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM−1 s−1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM−1 s−1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides. [ABSTRACT FROM AUTHOR]

Asymmetric propargylic substitution (APS) reactions play a crucial role in synthesizing the fundamental structural units found in natural drug molecules and macromolecules. However, achieving both high yield and enantioselectivity in the synthesis of asymmetric alkynyl propyl compounds remains a formidable challenge. In this study, we present a comprehensive computational study of asymmetric alkynyl propyl hydroxyaminations catalyzed by a chiral phosphine–nickel complex. The entire catalysis can be outlined as three stages: (i) activation of propargylic carbonate 1a by the (S)-L1/Ni(0) catalyst results in Ni(II)-intermediate IM2A. (ii) Decarboxylation of IM2A, leading to Ni(II)-complex IM5A. (iii) Asymmetric propargylic substitution of IM5A with N-hydroxyphthalimide 2a to give the more stable Ni(0)-complex IM7A, followed by product (S)-3a liberation and IM1A regeneration for the next catalytic cycle with the assistance of another equiv 1a. The asymmetric propargylic substitution step, with a barrier of 21.4 kcal mol−1, should be the rate-determining step and enantioselectivity-determining step during the whole catalysis. EDA–NOCV analysis revealed that the origins of the enantioselectivity of product (S)-3a lie in the combined effects of the ligand–substrate electrostatic interactions, orbital interactions, Pauli repulsions, and dispersion interactions. Based on mechanistic study, a new biaryl bisphosphine ligand (i.e., (S)-L6) affording higher enantioselectivity was designed, which will help to improve current catalytic systems and facilitate the development of new Ni-catalyzed asymmetric alkynyl propyl hydroxyaminations. [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]