Search Results (90)

The use of water as a nucleophile in catalytic asymmetric reactions remains a significant challenge, primarily due to its intrinsically low nucleophilicity and small size, which make precise control over both reactivity and stereoselectivity particularly difficult. To address this issue, we developed a CPA-catalyzed asymmetric hydrolysis system, successfully achieving the efficient and highly stereoselective transformation of 4H-oxazines with water. Under this catalytic system, the initial formation of chiral α-bromo ketones is followed by their in situ conversion through reduction and intramolecular S_N2 reactions, directly affording valuable chiral bromo alcohols and chiral oxazolone derivatives in high yields with excellent enantioselectivity. Full article

Chirality has emerged as a critical determinant in the design, efficacy, and environmental behavior of modern insecticides. While a significant proportion of agrochemicals are inherently chiral, most are still commercialized as racemic mixtures, despite well-documented differences in biological activity, toxicity, and degradation pathways between enantiomers. In this review, we provide a comprehensive and critical analysis of advances in the stereoselective synthesis and resolution of chiral insecticides, with particular emphasis on neonicotinoids, pyrethroids, and oxadiazines, including indoxacarb. A systematic survey of the literature (1985–2025), including peer-reviewed articles and patents, reveals that multiple strategies have been developed to access enantiomerically enriched compounds, including asymmetric organocatalysis, transition-metal catalysis, chiral-pool approaches, biocatalytic transformations, and chromatographic resolution techniques. Among these, recent developments in photoredox catalysis, recyclable metal complexes, and enzyme-mediated processes have significantly improved enantioselectivity and scalability, bridging the gap between academic methodologies and industrial applications. Despite these advances, challenges remain in achieving cost-effective, sustainable, and universally applicable asymmetric processes. Importantly, the relationship between stereochemistry and biological performance underscores the need for integrating synthetic chemistry with toxicological and environmental studies. Future directions point toward the incorporation of green chemistry principles, continuous-flow processes, and computational tools, including machine learning and molecular modeling, to accelerate the rational design of enantiopure agrochemicals. This review highlights both the progress achieved and the critical gaps that must be addressed to realize the potential of stereoselective insecticide development fully. Full article

Axially chiral compounds, indispensable in asymmetric catalysis, drug discovery, and materials science, have witnessed transformative advancements in synthesis through organocatalytic kinetic resolution (OKR) over the past decade. This review systematically dissects the latest achievements (2010–2025) in OKR, focusing on catalyst design, mechanistic insights, substrate diversification, and synthetic applications across C–C biaryl, C–N heterobiaryl, and olefinic axially chiral frameworks. By harnessing non-covalent interactions, OKR has emerged as a powerful strategy to overcome the challenges of low rotational barriers and limited stereocontrol, offering sustainable and enantioselective access to privileged chiral scaffolds. Furthermore, the current challenges and future prospects in this rapidly evolving field are assessed. Full article

Noble metal-catalyzed C–H activation has transformed synthetic methodology by enabling direct modification of inert C–H bonds with high levels of efficiency, selectivity, and functional group tolerance. This mini-review provides a focused overview of the mechanistic foundations and emerging advances in C–H functionalization mediated by ruthenium, iridium, rhodium and palladium catalysts. Key activation modes including oxidative addition, concerted metalation deprotonation (CMD), and electrophilic pathways are discussed alongside the roles of high-valent intermediates and ligand control in determining reactivity and regioselectivity. Special emphasis is placed on recent electrochemical strategies, where anodic oxidation replaces traditional chemical oxidants, granting access to unique redox manifolds and expanding the scope of C–C, C–N, C–O, and C–X bond-forming reactions. Representative transformations highlight the versatility of noble metals in constructing heterocycles, enabling enantioselective processes, and facilitating late-stage functionalization of complex molecules. Current challenges and future perspectives are outlined, including the need for improved nondirected activation, deeper mechanistic insight, and enhanced scalability. Collectively, this review underscores the central role of noble metals in advancing sustainable and innovative C–H functionalization chemistry. Full article

Apart from in hydrosilylation, platinum has traditionally played a limited role in homogeneous catalysis due to its high thermodynamic stability and lower intrinsic reactivity compared to other group 10 metals. However, the emergence of N-heterocyclic carbene (NHC) ligands has substantially broadened the catalytic profile of transition metals by enabling access to new mechanistic pathways and enhancing robustness under demanding conditions. This review summarizes advances in Pt–NHC catalysis reported between 2010 and 2025. These transformations encompass hydrosilylation of amides and CO₂, hydroboration and diboration, hydroamination, alkyne hydration, hydrogenation, selective alkyne dimerization, Suzuki–Miyaura coupling, arene C–H borylation, and cycloisomerization reactions, in which NHC ligands enhance bond activation, control regio- and stereoselectivity, and stabilize reactive Pt intermediates, including chiral architectures, enabling high enantioselectivity. Full article

Daedaleanol B is a drimane-derived merosesquiterpenoid isolated from the brown-rot fungus Daedalea incana. Herein, we report its first enantioselective total synthesis from commercially available (+)-sclareolide. A one-pot transformation afforded 11-acetoxy drimane-8α-ol, which was saponificated and selectively esterified with enantiopure L-pyroglutamic acid to give crystalline hydroxy-daedaleanol. Single-crystal X-ray diffraction of this intermediate, together with the known configuration of the chiral starting materials, enabled assignment of the absolute configuration of the daedaleanol B framework. Final elimination provided daedaleanol B, whose NMR data matched those reported for the natural product. Both hydroxy-daedaleanol and daedaleanol B exhibited time- and concentration-dependent antiproliferative effects in HT-29 colorectal cancer cells, with higher activity observed for daedaleanol B. Full article

This study researches the underexplored potential of the palladium-catalyzed Hayashi–Miyaura reaction in asymmetric synthesis, focusing on the preparation of novel derivatives of 2,2-diaryl-1-nitroethanes. These compounds are of interest as potential building blocks in medicinal and materials chemistry, yet they remain largely unexamined in enantioselective transformations. The study specifically targets three challenging substrates: 1,3-dimethoxy-5-(2-nitro-1-(o-tolyl)ethyl)benzene, 2-(2-nitro-1-phenylethyl)phenol, and 4-(2-nitro-1-phenylethyl)phenol. These molecules were selected to probe the reaction’s tolerance toward ortho-substitution and free hydroxyl groups—features known to complicate catalytic processes. Full article

Background: Carbohydrate-derived chiral ligands are promising tools in asymmetric catalysis due to their structural diversity, chirality, and availability. However, ligands based on galactose or sorbose have been scarcely explored in the enantioselective addition of dialkylzinc reagents to aldehydes. Methods: A series of chiral diols and β-amino alcohols was synthesized from methyl D-glucopyranoside, methyl D-galactopyranoside, and D-fructose. These ligands were tested in the titanium tetraisopropoxide-promoted enantioselective addition of diethylzinc to aromatic and aliphatic aldehydes. Results: Several ligands, particularly those with a D-fructopyranose backbone, exhibited excellent catalytic activity, with conversion rates up to 100% and enantioselectivities up to 96% ee. Notably, this study reports for the first time the use of β-amino alcohols derived from fructose and sorbose in this transformation. Conclusions: Carbohydrate-based ligands represent effective, inexpensive, and structurally versatile scaffolds for developing highly enantioselective catalysts, expanding the utility of sugars in asymmetric organometallic reactions. Full article

Axially chiral compounds play a pivotal role in organic synthesis, materials science, and pharmaceutical development. Among the various strategies for their construction, enantioselective iodination and bromination have emerged as powerful and versatile approaches, enabling the introduction of halogen functionalities that serve as valuable synthetic handles for further transformations. This review highlights recent advances in atroposelective iodination and bromination, with a particular focus on the synthesis of axially chiral biaryl and heterobiaryl frameworks. Key catalytic systems are discussed, including transition metal complexes, small-molecule organocatalysts, and high-valent metal catalysts in combination with chiral ligands or transient directing groups. Representative case studies are presented to elucidate mechanistic pathways, stereochemical induction models, and synthetic applications. Despite notable progress, challenges remain, such as expanding substrate scope, improving atom economy, and achieving high levels of regio- and stereocontrol in complex molecular settings. This review aims to provide a comprehensive overview of these halogenation strategies and offers insights to guide future research in the atroposelective synthesis of axially chiral molecules. Full article

Farrerol, a bioactive compound found in Folium Rhododendri daurici, demonstrates various biological and pharmacological effects. Nevertheless, the stereoselectivity of in vivo processes and bioactivity between its enantiomers have not been thoroughly investigated. This study aimed to explore the stereoselectivity and pharmacological activity variations in farrerol enantiomers, focusing on stereoselective pharmacokinetics, tissue distribution, in vitro metabolism using liver microsomes, in vivo intestinal absorption, molecular simulations of binding affinity with antiproliferative target, and cell viability assessed through the CCK-8 assay. The findings indicated that the pharmacokinetic characteristics of farrerol in rats’ plasma, liver, and kidney tissues displayed enantioselectivity after intragastric administration. Then, no chiral transformation between farrerol enantiomers was observed in the rat plasma when (+)-farrerol and (−)-farrerol were orally administered. Additionally, there are notable stereoselective differences in the inhibition of CYP 1A2, CYP 2C9, CYP 2C19, and CYP 3A4/5 enzymes by (+)-farrerol and (−)-farrerol (p < 0.01). These differences may contribute to the stereoselectivity observed in the hepatic metabolism of the two enantiomers of farrerol. In addition, there were selective differences in the binding of farrerol enantiomers to anti-proliferative targets, including UCHL3, STAT3β, PTP1B, and GSK3β. Farrerol enantiomers exhibited similar growth inhibitory effects in HT-29 cell. Overall, our work will provide a solid theoretical basis and experimental reference for the further development and utilization of farrerol enantiomers. Full article

A chiral gelator (R)-H₆L with multiple carboxyl groups based on a 1,1′-bi-2,2′-naphthol (BINOL) skeleton was prepared, and it could form a supramolecular gel under the induction of water in DMSO/H₂O and DMF/H₂O (1/1, v/v). In the EtOH/H₂O system, the original partial gel transformed into a stable metal–organic gel (MOG), specifically with Cu²⁺ among 20 metal ions. It is proposed that Cu²⁺ coordinates with the carboxyl groups of (R)-H₆L to form a three-dimensional network structure. With the addition of a variety of α-hydroxy acids and amino acids, the Cu²⁺-MOG collapsed with merely 0.06 equivalents of L-tartaric acid (L-TA), while other acids required much larger amounts to achieve the same effect, realizing the visual chemoselective and enantioselective recognition of tartaric acid. Therefore, the chiral gelator (R)-H₆L achieved the tandem visual recognition of Cu²⁺ and chiral tartaric acid by sequence gel formation and collapse, offering valuable insights for visual sensing applications and serving as a promising model for future chiral sensor design. Full article

Enantioselective transition metal catalysis is undoubtedly a cornerstone at the frontier of chemistry, attracting intense interest from both academia and the pharmaceutical industry. Central to this field is the strategic utilization of noncovalent interactions (NCIs), including hydrogen bonding, ion pairing, and π-system engagements, which not only drive asymmetric synthesis but also enable precise stereochemical control in transition metal-catalyzed transformations. Recent breakthroughs have unveiled a new generation of rationally designed ligands that exploit ligand–substrate noncovalent interactions, emerging as indispensable tools for stereocontrolled synthesis and setting new paradigms in ligand engineering. These advancements establish a transformative framework for ligand engineering, bridging fundamental mechanistic insights with practical synthetic utility. In this review, the judicious design concepts and syntheses of novel ligands from the past five years were highlighted and their synthetic applications in asymmetric catalysis were detailed. Full article

Chiral pincer complexes, characterized by their rigid tridentate coordination framework, have emerged as powerful catalysts in asymmetric synthesis. This review provides a comprehensive overview of recent advancements in the development of chiral pincer-type ligands and their corresponding transition metal complexes. We highlight the latest progress in their application across a range of catalytic asymmetric reactions, including the (transfer) hydrogenation of polar and non-polar bonds, hydrophosphination, alkynylation, Friedel-Crafts reactions, enantioselective reductive cyclization of alkynyl-tethered cyclohexadienones, enantioselective hydrosilylation, as well as Aza–Morita–Baylis–Hillman reactions. The structural rigidity and tunability of chiral pincer complexes enable precise control over stereoselectivity, resulting in high enantioselectivity and efficiency in complex molecular transformations. As the field advances, innovations in ligand design and the exploration of new metal centers are expected to expand the scope and utility of these catalysts, bearing significant implications for the synthesis of enantioenriched compounds in pharmaceuticals, materials science, and beyond. Full article

Metal carbenes are widely acknowledged as a category of highly effective intermediates that facilitate otherwise inaccessible transformations. In recent decades, carbene chemistry has made considerable advances and has demonstrated remarkable abilities in the formation of diverse chemical bonds and the synthesis of structurally distinctive molecules. Nevertheless, the majority of research within this field has concentrated on α-carbon-substituted carbenes, with comparatively little investigation of carbenes that have been functionalized with a wider structural variety, particularly those that have been substituted with heteroatoms (e.g., O, N, P, S, Si, Ge, Sn and B). The objective of this review is to elucidate the advancements in enantioselective transfer reactions involving metal carbenes substituted with these elements, thereby highlighting their contribution to the expansion of the structural diversity and synthetic utility of carbenes in contemporary chemistry. Full article

A library of regioisomeric monoterpene-based aminodiols was synthesised and applied as chiral catalysts in the addition of diethylzinc to benzaldehyde. The synthesis of the first type of aminodiols was achieved starting from (−)-8,9-dihydroperillaldehyde via reductive amination, followed by Boc protection and dihydroxylation with the OsO₄/NMO system. Separation of formed stereoisomers resulted in a library of aminodiol diastereoisomers. The library of regioisomeric analogues was obtained starting from (−)-8,9-dihydroperillic alcohol, which was transformed into a mixture of allylic trichloroacetamides via Overman rearrangement. Changing the protecting group to a Boc function, the protected enamines were subjected to dihydroxylation with the OsO₄/NMO system, leading to a 71:16:13 mixture of diastereoisomers, which were separated, affording the three isomers in isolated form. The obtained primary aminodiols were transformed into secondary derivatives. The regioselectivity of the ring closure of the N-benzyl-substituted aminodiols with formaldehyde was also investigated, resulting in 1,3-oxazines in an exclusive manner. To explain the stability difference between diastereoisomeric 1,3-oxazines, a series of comparative theoretical modelling studies was carried out. The obtained potential catalysts were applied in the reaction of aromatic aldehydes and diethylzinc with moderate to good enantioselectivities (up to 94% ee), whereas the opposite chiral selectivity was observed between secondary aminodiols and their ring-closed 1,3-oxazine analogues. Full article