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The first enantioselective Friedel‐Crafts (FC) allenylation reaction for the creation of central chirality is developed under cooperative Ir(I)/(phosphoramidite,olefin) and Lewis acid catalysis. This enantioconvergent reaction utilizes racemic allenylic alcohol as the electrophile and shows compatibility with a variety of electron‐rich arenes and heteroarenes. The resulting highly enantioenriched (up to >99.5 : 0.5 e.r.) 1,1‐disubstituted allenylic methanes, bearing a benzylic carbon stereocenter, are obtained with complete regiocontrol – both on (hetero)arenes as well as on the allenylic fragment. This protocol allows for the enantioselective formal introduction of a 4‐carbon alkyl chain into (hetero)arenes, along with the creation of a benzylic stereocenter. Judicious synthetic elaborations not only lead to formal enantioselective FC alkylation products of less electron‐rich arenes but also of substituted arenes in ortho‐ and even meta‐selective fashion. An intramolecular version of this FC allenylation is shown to proceed with promising enantioselectivity under the same catalytic conditions. Mechanistic studies revealed the involvement of dynamic kinetic asymmetric transformation (DyKAT) of racemic allenylic alcohols in this reaction. [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed asymmetric allylic substitution reactions represent a hot research topic in the field of asymmetric synthesis, with significant progress having been made. Among diverse catalysis systems, relay catalysis enables sequential activation of multiple steps in one pot and the rapid construction of multiple chiral centers, providing a simple and powerful platform for organic synthesis. Recently, relay catalysis has been successfully applied to asymmetric allylic substitution reactions, and a variety of challenging transformations have been realized. This Short Review summarizes the related progress on asymmetric allylic substitution reactions based on relay catalysis over the last decade. 1 Introduction 2 The General Transformation Model 3 Allylation Relays Further Reaction 4 Initial Reaction Relays Allylation 5 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Chiral organofluorine compounds featuring a monofluoromethyl (CH2F)-substituted stereocenter are often encountered in a number of drugs and bioactive molecules. Consequently, the development of catalytic asymmetric methods for the enantioselective construction of CH2F-substituted stereocenters has made great progress over the past two decades, and a variety of enantioselective transformations have been accordingly established. According to the types of fluorinated reagents or substrates employed, these protocols can be divided into the following major categories: (i) enantioselective ring opening of epoxides or azetidinium salts by fluoride anions; (ii) asymmetric monofluoromethylation with 1-fluorobis(phenylsulfonyl)methane; (iii) asymmetric fluorocyclization of functionalized alkenes with Selectfluor; and (iv) asymmetric transformations involving α-CH2F ketones, α-CH2F alkenes, or other CH2F-containing substrates. This feature article aims to summarize these recent advances and discusses the possible reaction mechanisms, advantages and limitations of each protocol and their applications. Synthetic opportunities still open for further development are illustrated as well. This review article will be an inspiration for researchers engaged in asymmetric catalysis, organofluorine chemistry, and medicinal chemistry. [ABSTRACT FROM AUTHOR]

The use of light energy to drive asymmetric organic transformations to produce high-value-added organic compounds is attracting increasing interest as a sustainable strategy for solving environmental problems and addressing the energy crisis. Chiral covalent organic frameworks (COFs), as porous crystalline chiral materials, have become an important platform on which to explore new chiral photocatalytic materials due to their precise tunability, chiral structure, and function. This review highlights recent research progress on chiral COFs and their crystalline composites, evaluating their application as catalysts in asymmetric photocatalytic organic transformations in terms of their structure. Finally, the limitations and challenges of chiral COFs in asymmetric photocatalysis are discussed, with future opportunities for research being identified. [ABSTRACT FROM AUTHOR]

A Rh‐catalyzed asymmetric hydroboration of dialkyl ketone‐derived silyl enol ethers with HBpin has been developed using a commercially available catalyst and ligand ([RhCl (cod)]2 and MeO‐BIBOP). A variety of silyl enol ethers undergo this asymmetric transformation, providing the corresponding products with high enantioselectivity (up to 97 : 3 % er). In addition, the utility of this protocol is demonstrated by the versatile transformation of chiral borylether products to a range of valuable derivatives. [ABSTRACT FROM AUTHOR]

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

Planar‐chiral skeletons widely exist in natural products, bioactive compounds, and other functional molecules. Although significant progress has been made in the field of asymmetric synthesis of centrally or axially chiral molecules over the past years, enantioselective constructing of planar chirality is still a big obstacle and numerous efforts have been made in this field. Previous works have mainly focused on the assembly of planar‐chiral [2,2]‐paracyclophanes and metallocenes. This Minireview describes recent advancements in asymmetric catalytic synthesis of planar‐chiral macrocycles, including ansa chain construction, plane formation and asymmetric transformation strategies. It is anticipated that this Minireview will sever as a source of inspiration for developing new unconventional procedures for access to planar‐chiral skeletons. [ABSTRACT FROM AUTHOR]

P‐stereogenic phosphorus compounds are essential across various fields, yet their synthesis via enantioselective P−C bond formation remains both challenging and underdeveloped. We report the first copper‐catalyzed enantioselective hydrophosphorylation of alkynes, facilitated by a newly designed chiral 1,2‐diamine ligand. Unlike previous methods that rely on kinetic resolution with less than 50 % conversion, our approach employs a distinct dynamic kinetic asymmetric transformation mechanism, achieving complete conversion of racemic starting materials. This reaction is compatible with a broad range of aromatic and aliphatic terminal alkynes, producing products with high yields (up to 95 %), exclusive cis selectivity, and exceptional regio‐ and enantioselectivity (>20 : 1 r.r. and up to 96 % ee). The resulting products were further transformed into a diverse array of enantioenriched P‐stereogenic scaffolds. Preliminary mechanistic studies were conducted to elucidate the reaction details. [ABSTRACT FROM AUTHOR]

The synthesis of asymmetric organic molecules has experienced a huge development over the last few decades. Phase‐transfer catalysis has been proven to be one of the most powerful methods for these asymmetric transformations. However, the study of the mechanism of these catalysts and the different interactions that they can establish with the reactants has failed to keep pace. In the present study, the conjugate cyanation of two different α,β‐unsaturated ketones are studied in the presence of a well‐known alkaloid quinine‐derived PTC, along with different modifications. The study includes the comparison of different binding modes between the catalysts and the different reactants, the mechanistic study of the reaction and the analysis of the non‐covalent interactions established within the complexes and their role in the global enantioselectivity of the process. [ABSTRACT FROM AUTHOR]

The ubiquitous nature of amines in drug compounds, bioactive molecules and natural products has fueled intense interest in their synthesis. Herein, we introduce a nickel‐catalyzed enantioconvergent allenylic amination of methanol‐activated allenols. This protocol affords a diverse array of functionalized allenylic amines in high yields and with excellent enantioselectivities. The synthetic potential of this method is demonstrated by employing bioactive amines as nucleophiles and conducting gram‐scale reactions. Furthermore, mechanistic investigations and DFT calculations elucidate the role of methanol as an activator in the nickel‐catalyzed reaction, facilitating the oxidative addition of the C−O bond of allenols through hydrogen‐bonding interactions. The remarkable outcomes arise from a rapid racemization of allenols enabled by the nickel catalyst and from highly enantioselective dynamic kinetic asymmetric transformation of η3‐alkadienylnickel intermediates. [ABSTRACT FROM AUTHOR]

Predicting student performance is crucial for both preventing failure and enabling personalized teaching-and-learning strategies. The digitalization of educational institutions has led to the collection of extensive student learning data over the years. Current research primarily focuses on short-term data, e.g. a single year or semester. In contrast, long-term data has the potential to offer a deeper insight into student behavior, thereby increasing the accuracy of predictions. However, the direct application of long-term data in prediction models assumes consistent data distributions over time. In the real world, evolutions in course content and structure can lead to variations in feature spaces (heterogeneity) and distribution shifts across different academic years, compromising the effectiveness of prediction models. To address these challenges, we introduce the Learning Ability Self-Adaptive Algorithm (LASA), which can adapt to the evolving feature spaces and distributions encountered in long-term data. LASA comprises two primary components: Learning Ability Modeling (LAM) and Long-term Distribution Alignment (LTDA). LAM assumes that students' responses to exercises are samples from distributions that are parameterized by their learning abilities. It then estimates these parameters from the heterogeneous student exercise response data, thereby creating a new homogeneous feature space to counteract the heterogeneity present in long-term data. Subsequently, LTDA employs multiple asymmetric transformations to align distributions of these new features across different years, thus mitigating the impact of distribution shifts on the model's performance. With these steps, LASA can generate well-aligned features with meaningful semantics. Furthermore, we propose an interpretable prediction framework including three components, i.e. LASA, a base classifier for outcome predictions, and Shapley Additive Explanations (SHAP) for elucidating the impact of specific features on student performance. Our exploration of long-term student data covers an eight-year period (2016-2023) from a face-to-face course at Tsinghua University. Comprehensive experiments demonstrate that leveraging long-term data significantly enhances prediction accuracy compared to short-term data, with LASA achieving up to a 7.9% increase. Moreover, when employing long-term data, LASA outperforms state-of-the-art models, ProbSAP and SFERNN, by an average accuracy improvement of 6.8% and 6.4%, respectively. We also present interpretable insights for pedagogical interventions based on a quantitative analysis of feature impacts on student performance. To the best of our knowledge, this study is the first to investigate student performance prediction in long-term data scenarios, addressing a significant gap in the literature. [ABSTRACT FROM AUTHOR]

This paper highlights the latest advancements in asymmetric alkylative difunctionalization of carbon–carbon double bonds by utilizing aliphatic C─H substrates as alkyl radical precursors. By integrating different hydrogen atom transfer (HAT) processes with various transition metal catalytic systems, various alkane substrates can be efficiently converted into corresponding alkyl radicals, which then participate in radical additions to carbon–carbon double bonds followed by stereoselective functionalizations with a third component. These strategies leverage inexpensive, abundant, and readily available alkane feedstocks to rapidly construct complex chiral molecules, demonstrating high step and atom economy. This paper focuses on recent progress and applications in this area, provides a comprehensive perspective on current developments, and suggests future directions in alkane‐involved asymmetric transformations. [ABSTRACT FROM AUTHOR]

Hydrophosphination and oxyphosphination are two important topical reactions in order to prepare organophosphorus derivatives from unsaturated derivatives such as alkenes and alkynes in a more sustainable fashion. Noticeably, metal catalysed versions have shown great interest and efficiency. By contrast, the use of earth abundant transition metal based catalysts for such transformations is less reported, even if there is a growing interest during the last decade. This review article reports and highlights recent developments using manganese, iron, cobalt, nickel and copper based catalysts for hydro‐ and oxyphosphination, notably exhibiting the selectivity, functional group tolerance, milder conditions and catalyst design. Even if significant progresses were made, the scopes are still rather limited (mainly focused on activated olefins such as styrenes) and chemo‐ and stereo‐selectivity issues still have to be solved, notably for asymmetric transformations. Of interest, the use of visible light including blue one as activator emerged, giving promising and stimulating results at ambient conditions. [ABSTRACT FROM AUTHOR]

A symmetric anion mediated dynamic kinetic asymmetric Knoevenagel reaction was established as a general and efficient method for accessing both N−C and N−N atropisomers. The resulting highly enantio‐pure pyridine‐2,6(1H,3H)‐diones exhibit diverse structures and functional groups. The key to excellent regio‐ and remote enantiocontrol could be owed to the hydrogen bond between the enolate anion and triflamide block of the organocatalyst. This connected the enolate anion and iminium cation by a chiral backbone. The mechanism investigation via control experiments, correlation analysis, and density functional theory calculations further revealed how the stereochemical information was transferred from the catalyst into the axially chiral pyridine‐2,6(1H,3H)‐diones. The synthetic applications also demonstrated the reaction's potential. [ABSTRACT FROM AUTHOR]

This review highlights the use of DACH as a versatile ligand in catalytic asymmetric transformations providing mechanistic rationales and relevant comments presented in chronological order for each of the 21 reaction types with references up to December 25, 2023. Intended to be as practically comprehensive as possible, this review assembles useful examples of using DACH as a ligand in organocatalytic or as metal complexes in asymmetric transformations. The resulting enantiomerically enriched, if not pure, chiral non-racemic small molecules are of great utility as value added intermediates in the total synthesis of natural products, in the design and synthesis of medicinally important compounds, and in other areas in organic and bioorganic chemistry where chirality plays a role. The graphic image depicts Spartacus with his arms folded in the same sense of chirality as (R , R)-DACH. 1 Introduction 2 DACH: A Brief Historical Narrative 3 Catalytic Asymmetric Hydrogenation of Alkenes 4 Catalytic Asymmetric Dihydroxylation of Alkenes 5 Catalytic Asymmetric Sulfoxidation and Sulfimidation 6 Catalytic Asymmetric 1,4-Conjugate Addition 6.1 Using Jacobsen's DACH Metal–salen Complexes as Catalysts 6.2 Using Takemoto's Bifunctional H-Bonding DACH Thiourea Organocatalyst 6.3 Using DACH Ni(II) Complexes as Catalysts 6.4 Using DACH H-Bonding Catalysis 7 Catalytic Asymmetric Epoxidation of Alkenes 8 Catalytic Asymmetric Claisen Rearrangement 9 Catalytic Asymmetric 1,2-Nucleophilic Addition to Carbonyl Compounds 9.1 Catalytic Asymmetric Addition of Dialkylzinc to Aldehydes and Ketones 9.2 Catalytic Asymmetric Alkynylation of Aldehydes and Ketones 9.3 Catalytic Asymmetric Addition of Cyanide to Aldehydes and Ketones 10 Catalytic Asymmetric Allylic Alkylation 11 Catalytic Asymmetric Cyclopropanation of Alkenes 12 Catalytic Asymmetric Cycloaddition Reactions 13 Catalytic Asymmetric Aziridination of Alkenes 14 Catalytic Asymmetric Hydrogenation of Prochiral Ketones and Imines 15 Catalytic Asymmetric Aldol Reactions 16 Catalytic Asymmetric Opening of Small Ring Systems 16.1 Desymmetrization of meso -Epoxides and meso -Aziridines 16.2 Kinetic Resolution of Racemic Epoxides 16.3 Enantioselective Addition of CO2 to Epoxides 16.4 Enantioselective Ring Opening of Oxetanes 17 Catalytic Asymmetric Strecker Reactions 18 Catalytic Asymmetric Mannich Reactions 19 Catalytic Asymmetric Henry and Aza-Henry Reactions 20 Catalytic Asymmetric Morita–Baylis–Hillman and Rauhut–Currier Reactions 21 Catalytic Asymmetric Petasis Reactions 22 Organocatalytic Asymmetric Cascade Reactions 23 Miscellaneous Catalytic Reactions 24 Conclusion and Outlook 25 DACH Catalysts and Ligands List [ABSTRACT FROM AUTHOR]

Silicon-stereogenic chiral organosilanes have found increasing applications in synthetic chemistry, medicinal chemistry, and materials science. In this context, various asymmetric catalytic methods have been established for the diverse synthesis of silicon-stereogenic silanes. In particular, asymmetric organocatalysis is emerging as an important and complementary synthetic tool for the enantioselective construction of silicon-stereocenters, along with the rapid development of chiral-metal catalyzed protocols. Its advent provides a powerful platform to achieve functionalized silicon-stereogenic organosilanes with structural diversity, and should lead to great development in chiral organosilicon chemistry. In this Tutorial Review, we highlight these latest achievements from two aspects: desymmetrizations of prochiral tetraorganosilanes and dynamic kinetic asymmetric transformations of racemic organosilanes by employing five organocatalytic activation modes. The advantages, limitations and synthetic value of each protocol, as well as the synthetic opportunities still open for further exploration, are also discussed. [ABSTRACT FROM AUTHOR]

PIII/PV redox cycling has recently emerged as a valuable strategy to minimized the chemical waste generated by phosphine‐mediated reaction, as well as enabling asymmetric transformation. In this article, we detail our contribution to this field by designing a series of diversely functionalized, electron‐rich bridgehead phosphine oxides with structural features that make them well‐suited as PIII/PV redox organocatalysts. Their catalytic performance has been assessed in various model reactions, including Wittig or Staudinger reactions, along with the reduction of activated alkenes and allenes. For each of these scenarios, we performed a comparative analysis with existing catalysts in order to demonstrate the applicability and limitation of methanophosphocines. [ABSTRACT FROM AUTHOR]

Lewis base/transition-metal cooperatively catalyzed asymmetric transformations have attracted extensive attention as they offer complementary catalytic systems within the realm of cooperative catalysis. Recently, the synergistic use of Lewis bases in combination with earth-abundant 3d metals has emerged as a fascinating prospect, presenting an opportunity to move away from the reliance on noble metals and to explore novel catalytic processes. In this Account, we highlight our recent achievements regarding the chemistry and synthetic utility of isothiourea (ITU) activated C1-ammonium enolates and N-heterocyclic carbene (NHC)-bound homoenolate equivalents in conjunction with 3d transition-metal activated electrophiles. The remarkable success in the stereoselective construction of carbon–carbon and carbon–heteroatom bonds has led to significant contributions to stereodivergent synthesis. 1 Introduction 2 ITU/Copper Cooperative Catalysis 3 NHC/Copper Cooperative Catalysis 4 NHC/Nickel Cooperative Catalysis 5 Conclusion [ABSTRACT FROM AUTHOR]

Unitary equivariance is a natural symmetry that occurs in many contexts in physics and mathematics. Optimization problems with such symmetry can often be formulated as semidefinite programs for a d p + q -dimensional matrix variable that commutes with U ⊗ p ⊗ U ¯ ⊗ q , for all U ∈ U (d) . Solving such problems naively can be prohibitively expensive even if p + q is small but the local dimension d is large. We show that, under additional symmetry assumptions, this problem reduces to a linear program that can be solved in time that does not scale in d, and we provide a general framework to execute this reduction under different types of symmetries. The key ingredient of our method is a compact parametrization of the solution space by linear combinations of walled Brauer algebra diagrams. This parametrization requires the idempotents of a Gelfand–Tsetlin basis, which we obtain by adapting a general method inspired by the Okounkov–Vershik approach. To illustrate potential applications of our framework, we use several examples from quantum information: deciding the principal eigenvalue of a quantum state, quantum majority vote, asymmetric cloning and transformation of a black-box unitary. We also outline a possible route for extending our method to general unitary-equivariant semidefinite programs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The concurrent implementation of cascade reactions that combine biocatalysis and chemocatalysis is a challenging undertaking. Electrocatalysis provides versatile catalytic abilities and allows for mild reaction conditions, offering the potential for designing concurrent chemoenzymatic cascade reactions. The research on bioelectrocatalysis has primarily concentrated on utilizing electrocatalysis to achieve cofactor regeneration of enzymes. In contrast with previous reports, herein, we developed a deracemization strategy involving the concurrent combination of biocatalytic reduction and anodic oxidation in an undivided cell to achieve chiral sulfoxides, demonstrating the good compatibility. We anticipate this study will offer an alternative pathway for the design of the cascade reaction combined with electrocatalysis and biocatalysis. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition metal‐catalyzed asymmetric hydrogenation is an efficient and direct synthetic method to access chiral compounds, which features simplicity, easy working‐up process, and high atomic economy. It typically relies on precious transition metal catalytic systems, including ruthenium, rhodium, iridium and palladium, which always face the difficulties of limited resources, high cost, and environmental contamination. Therefore, great efforts were made to apply earth‐abundant, low (non‐)toxic, and environmentally friendly transition metals, such as iron, cobalt, nickel and copper, to the asymmetric hydrogenation in the past decades, and some considerable breakthroughs have been obtained. In this review, we mainly summarized some recent research progress of nickel‐catalyzed asymmetric hydrogenation of prochiral unsaturated molecules, including olefins, imines and ketones. And continuous development of chiral nickel catalytic systems and the application of them into challenging asymmetric hydrogenation is prospected in the future. Key Scientists: Transition metal‐catalyzed asymmetric hydrogenation has been regarded as an important and direct approach to access chiral molecules. The first example of homogeneous catalytic asymmetric hydrogenation was developed by Knowles and Horner in 1968, respectively. In 1971, Kagan developed privileged chiral DIOP ligand for asymmetric hydrogenation. Halpern and Brown made deep studies on the Rh‐catalyzed asymmetric hydrogenation in 1977, respectively. Noyori developed a powerful and privileged chiral BINAP ligand in 1980. Owing to Knowles and Noyori's great contribution in the field of catalytic asymmetric hydrogenation, they were awarded the Nobel Prize in Chemistry in 2001. In 1984, Ohkubo developed pioneering earth‐abundant transition metal Ni‐catalyzed asymmetric hydrogenation of ethyl α‐methylcrotonate. A great many scientists made tremendous contribution to the development of chiral privileged ligands, such as, Bosnich, Kumada, Giongo, Takaya, Miyashima, Achiwa, Burk, Pflaltz, Chan, X. Zhang, Imamoto, Zhou, Genet, Sannicolo, Ding, Hoge, W. Zhang, Z. Zhang, Tang, these ligands owned wide application in the catalytic asymmetric hydrogenation. In addition, Zhou, Fan made deep investigation on the asymmetric hydrogenation of challenging aromatic heterocyclic compounds. Owing to the great importance of the development of the asymmetric (transfer) hydrogenation promoted by cheap transition metal catalytic systems, some researchers, such as Hamada, Gao, J. S. Zhou, Chirik, X. Zhang, Y.‐G. Zhou, W. Zhang, Lv, Dong, Fu, Deng, and Hou, made great efforts to the development of earth‐abundant nickel‐catalyzed asymmetric hydrogenation of prochiral unsaturated molecules, including olefins, imines and ketones. In addition, there are some other scientists that have also made great contribution to the development of catalytic asymmetric hydrogenation and Ni‐catalyzed asymmetric transformation, with too limited space to list all of them. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition metal‐catalyzed asymmetric hydrogenation is an efficient and direct synthetic method to access chiral compounds, which features simplicity, easy working‐up process, and high atomic economy. It typically relies on precious transition metal catalytic systems, including ruthenium, rhodium, iridium and palladium, which always face the difficulties of limited resources, high cost, and environmental contamination. Therefore, great efforts were made to apply earth‐abundant, low (non‐)toxic, and environmentally friendly transition metals, such as iron, cobalt, nickel and copper, to the asymmetric hydrogenation in the past decades, and some considerable breakthroughs have been obtained. In this review, we mainly summarized some recent research progress of nickel‐catalyzed asymmetric hydrogenation of prochiral unsaturated molecules, including olefins, imines and ketones. And continuous development of chiral nickel catalytic systems and the application of them into challenging asymmetric hydrogenation is prospected in the future. Key Scientists: Transition metal‐catalyzed asymmetric hydrogenation has been regarded as an important and direct approach to access chiral molecules. The first example of homogeneous catalytic asymmetric hydrogenation was developed by Knowles and Horner in 1968, respectively. In 1971, Kagan developed privileged chiral DIOP ligand for asymmetric hydrogenation. Halpern and Brown made deep studies on the Rh‐catalyzed asymmetric hydrogenation in 1977, respectively. Noyori developed a powerful and privileged chiral BINAP ligand in 1980. Owing to Knowles and Noyori's great contribution in the field of catalytic asymmetric hydrogenation, they were awarded the Nobel Prize in Chemistry in 2001. In 1984, Ohkubo developed pioneering earth‐abundant transition metal Ni‐catalyzed asymmetric hydrogenation of ethyl α‐methylcrotonate. A great many scientists made tremendous contribution to the development of chiral privileged ligands, such as, Bosnich, Kumada, Giongo, Takaya, Miyashima, Achiwa, Burk, Pflaltz, Chan, X. Zhang, Imamoto, Zhou, Genet, Sannicolo, Ding, Hoge, W. Zhang, Z. Zhang, Tang, these ligands owned wide application in the catalytic asymmetric hydrogenation. In addition, Zhou, Fan made deep investigation on the asymmetric hydrogenation of challenging aromatic heterocyclic compounds. Owing to the great importance of the development of the asymmetric (transfer) hydrogenation promoted by cheap transition metal catalytic systems, some researchers, such as Hamada, Gao, J. S. Zhou, Chirik, X. Zhang, Y.‐G. Zhou, W. Zhang, Lv, Dong, Fu, Deng, and Hou, made great efforts to the development of earth‐abundant nickel‐catalyzed asymmetric hydrogenation of prochiral unsaturated molecules, including olefins, imines and ketones. In addition, there are some other scientists that have also made great contribution to the development of catalytic asymmetric hydrogenation and Ni‐catalyzed asymmetric transformation, with too limited space to list all of them. [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]

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]

P‐chiral supramolecular phosphine ligands are crucial for asymmetric transformations, but their synthesis is tedious. We report a one‐step synthesis of thermally stable P‐chiral supramolecular phosphines and their performance in the asymmetric hydrogenation of functionalized alkenes. A rational designing and synthesis of (R, R)‐QuinoxP* ligated palladium complex (Pd‐2) in excellent yield is reported. This Pd‐2 catalyzed a direct P−C coupling of 2,3‐dihydro‐1‐H‐phosphindole (A1)/1,2,3,4‐tetrahydrophosphindoline (A2) with 1‐(3‐iodophenyl)urea (B1)/2‐iodo /6‐hydroxy pyridine (B2) and,produced corresponding ligands L1–L3. The P−C coupling between A1 and B2 produced 6‐(2,3‐dihydro‐1H‐phosphindol‐1‐yl)pyridine‐2(1H)‐one (L2) with an excellent enantiomeric excess of up to 99 %. L2 was found to be remarkably stable even at 150 °C and did not oxidize/hydrolyze for at least 24 hours in open air. Such thermal stability and an impediment to oxidation are unprecedented. L2 self‐assembled and produced L2−C1 (Pt), L2−C2(Pd), and L2−C3(Rh) assemblies. The utility of the self‐assembled P‐chiral ligand was demonstrated in the Rh‐catalyzed asymmetric hydrogenation (AH) of functionalized olefins. The L2−C3 catalyzed AH of functionalized alkenes and delivered chiral products with excellent enantioselectivity of >99 %. A small library of 16 substrates was subjected to AH using L2−C3 to produce chiral compounds with excellent conversion and ee. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Axially chiral biaryls represent the most important class of atropisomers, and they widely exist in natural products and biologically active molecules. They also constitute a unique scaffold for chiral ligands and catalysts in organic synthesis. The development of synthetic methods to obtain such chiral compounds has received widespread attention, among which catalytically atroposelective ring‐opening of configurationally labile compounds represents one of the most attractive strategies. Various substrates with strained cyclic structures, such as the renowned Bringmann's lactones, can undergo asymmetric transformation into stable atropisomers. Known advancement primarily relies on metal catalyst combined with well‐designed chiral ligands, the approaches utilizing organocatalysis as a critical resolution strategy are notably scarce. In this study, we disclosed a N‐heterocyclic carbene (NHC)‐catalyzed asymmetric ring‐opening reaction of biaryl lactams via direct atroposelective nucleophilic activation. The optimized bulky carbene catalyst ensures that the reaction can proceed under mild conditions, affording the desired product with good to excellent yields and atroposelectivity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Axially chiral biaryls represent the most important class of atropisomers, and they widely exist in natural products and biologically active molecules. They also constitute a unique scaffold for chiral ligands and catalysts in organic synthesis. The development of synthetic methods to obtain such chiral compounds has received widespread attention, among which catalytically atroposelective ring‐opening of configurationally labile compounds represents one of the most attractive strategies. Various substrates with strained cyclic structures, such as the renowned Bringmann's lactones, can undergo asymmetric transformation into stable atropisomers. Known advancement primarily relies on metal catalyst combined with well‐designed chiral ligands, the approaches utilizing organocatalysis as a critical resolution strategy are notably scarce. In this study, we disclosed a N‐heterocyclic carbene (NHC)‐catalyzed asymmetric ring‐opening reaction of biaryl lactams via direct atroposelective nucleophilic activation. The optimized bulky carbene catalyst ensures that the reaction can proceed under mild conditions, affording the desired product with good to excellent yields and atroposelectivity. [ABSTRACT FROM AUTHOR]

Chiral imidazolidin-2-ones are a kind of important N-heterocycles in bioactive molecules and can be converted to valuable chiral vicinal diamines. It is of great significance to develop catalytic asymmetric transformations for the synthesis of chiral N -heterocycles which play a significant role in drug development. Herein, an asymmetric intramolecular C(sp³)--H amination of N-benzoyloxyurea via 1,5-hydrogen atom transfer (HAT) is developed by using earth-abundant iron as the catalyst and chiral amino-acid derived phenanthroline as ligand, affording a series of chiral imidazolidinones in moderate-to-good yields (up to 68%) and enantiomeric ratios (up to 81:19). It is worth noting that this is one of the very few examples of iron-catalyzed enantioselective intramolecular C(sp³)--H aminations realized with a nonenzymatic catalyst. [ABSTRACT FROM AUTHOR]

This research Account describes the development of chiral organocatalysts, focusing on diphenyl-2-pyrrolidinemethanol and its derivatives as valuable tools in asymmetric transformations. The research also includes the discovery of a novel anionic Si→C alkyl migration method, which has been developed into a one-pot procedure for synthesizing (E)-chalcones from hydroxyamide and N , N -diethylcarbamates. The findings underscore the potential of sulfide and silicon as valuable reagents for organic synthesis and emphasize the importance of exploring new reaction pathways and mechanisms to discover novel synthetic methods. 1 Introduction 2 Synthesis of 2 and Sulfur Reagent as Chiral Lewis Acid 3 Sulfur/Selenium Reagent as Chiral Lewis Base 4 Anionic Si→C Alkyl Migration 5 Conclusion [ABSTRACT FROM AUTHOR]

Axially chiral thioethers and sulfoxides emerge as two pivotal classes of ligands and organocatalysts, which have remarkable features in the stereoinduction of various asymmetric transformations. However, the lack of easy methods to access such molecules with diverse structures has hampered their broader utilization. Herein, an oxidative kinetic resolution for sulfides using a chiral bifunctional squaramide as the catalyst with cumene hydroperoxide as the terminal oxidant is established. This asymmetric approach provides a variety of axially chiral thioethers as well as sulfoxides bearing both axial and central chirality, with excellent diastereo‐ and enantioselectivities. This catalytic system also successfully extends to the kinetic resolution of benzothiophene‐based sulfides. Preliminary mechanism investigation indicates that the multiple hydrogen bonding interactions between the bifunctional squaramide catalyst and substrates play a crucial role in determining the enantioselectivity and reactivity. [ABSTRACT FROM AUTHOR]

The precise synthesis of chiral small molecules is a core research area in chemical science. Deracemization, an appealing technology that converts racemate to its single enantiomer with the same constitution in theoretical 100 % yield, appears as a straightforward and efficient strategy in asymmetric synthesis. A cascading redox sequence was the most employed approach to drive deracemization through destroy and recreate the stereocenter in a given molecule. This review mainly focuses on the progress of redox deracemization driven by respective biocatalysis and chemo–catalysis. In particular, each section will be subdivided according to the action modes, the respective substrate classes and perspectives on future development. [ABSTRACT FROM AUTHOR]

Direct asymmetric hydrogenation (AH) and asymmetric transfer hydrogenation (ATH) are among the most efficient approaches to produce chiral building blocks. Recently, these types of transformations have witnessed a shift towards the use of molecular catalysts based on earth‐abundant transition metals due to their ready availability, economic advantage, and novel properties. With particular regard to manganese, catalyst development has seen both the efficiency and substrate scope in AH and ATH greatly improved, with the emergence of a large number of well‐defined Mn‐complexes employed in this field. The reaction scope includes the AH and ATH of C=O bonds, asymmetric reduction of C=N bonds and the asymmetric reductive transformations of C=C bonds. Herein, our survey of the area focuses on the catalytic activity of such complexes, their versatility towards asymmetric transformations and the routes employed to convert substrates to their target molecules. We consider the collected findings of this article will be helpful to the reader by providing an insight into ligand design, thereby aiding future catalyst development. Moreover, this review is aimed at highlighting the remarkable progress made in the last seven years in the development of manganese complexes for enantioselective reduction. [ABSTRACT FROM AUTHOR]

Axially chiral biaryl scaffolds are important in pharmaceuticals, natural products, and asymmetric synthesis. Atroposelective ring‐opening of configurationally labile biaryl reagents via dynamic kinetic asymmetric transformation provides a valuable approach to access axially chiral biaryl atropisomers. This review summarizes seminal contributions and recent advancements on this topic based on the use of different types of configurationally labile biaryl reagents. [ABSTRACT FROM AUTHOR]

A formal [4+2] annulation reaction of phthalaldehydes and 3‐ylideneoxindoles through a tandem process of a Stetter–aldol reaction was accomplished by the application N‐heterocyclic carbenes as effective catalysts. Under mild conditions, this unprecedented cascade reaction readily occurs in good yield, enabling straightforward access to functionalized tetrahydronaphthalene‐fused spirooxindoles. For the first time, the feasibility of an asymmetric Stetter–aldol reaction has also been briefly explored by employing chiral organic bases to promote the asymmetric transformation. [ABSTRACT FROM AUTHOR]

Near infrared (NIR) emitter with circularly polarized phosphorescence (CPP), known as NIR CPP, has emerged as a key part in the research of cutting‐edge luminescent materials. However, it remains a challenge to obtain nanoclusters with NIR CPP activity. Here, we propose an asymmetric transformation approach to efficiently synthesize two pairs of chiral silver nanoclusters (R/S‐Ag29 and R/S‐Ag16) using an achiral Ag10 nanocluster as starting material in the presence of different concentration chiral inducer (R/S)‐1,1′‐binaphthyl‐2,2′‐diyl hydrogenphosphate (R/S‐BNP). R/S‐Ag29, formed in the low‐concentration R/S‐BNP, exhibits a unique kernel‐shell structure consisting of a distorted Ag13 icosahedron and an integrated cage‐like organometallic shell with a C3 symmetry, and possesses a superatomic 6‐electron configuration (1S2|1P4). By contrast, R/S‐Ag16, formed in the high‐concentration R/S‐BNP, features a sandwich‐like pentagram with AgI‐pure kernel. Profiting from the hierarchically chiral structures and superatomic kernel‐dominated phosphorescence, R/S‐Ag29 exhibits infrequent CPP activity in the second near‐infrared (975 nm) region, being the first instance of NIR‐II CPP observed among CPL‐active metal nanoclusters. This study presents a new approach to reduce the difficulty of de novo synthesis for chiral silver nanomaterials, and facilitates the design of CPP‐active superatomic nanoclusters in NIR region. [ABSTRACT FROM AUTHOR]

The boracarboxylation reaction has potential for the production of natural products and drug candidates, but the development of an asymmetric version of this transformation is challenging. We report an enantioselective boracarboxylation of styrenes, enabled by a copper catalyst containing chiral phosphines. Our experimental conditions provide yields between 31–76% and enantiomeric ratios from 80:20 up to 98:2 for electron‐rich styrenes. Oxidation of a boracarboxylation product gives (S)‐tropic acid, an intermediate towards several tropane alkaloids. A computational analysis of the mechanistic details shows a complex pattern of competing reaction pathways, highlighting challenges encountered when developing asymmetric reactions using CO2. [ABSTRACT FROM AUTHOR]

Repurposing enzymes to catalyze non‐natural asymmetric transformations that are difficult to achieve using traditional chemical methods is of significant importance. Although radical C−O bond formation has emerged as a powerful approach for constructing oxygen‐containing compounds, controlling the stereochemistry poses a great challenge. Here we present the development of a dual bio‐/photo‐catalytic system comprising an ene‐reductase and an organic dye for achieving stereoselective lactonizations. By integrating directed evolution and photoinduced single electron oxidation, we repurposed engineered ene‐reductases to steer non‐natural radical C−O formations (one C−O bond for hydrolactonizations and lactonization‐alkylations while two C−O bonds for lactonization‐oxygenations). This dual catalysis gave a new approach to a diverse array of enantioenhanced 5‐ and 6‐membered lactones with vicinal stereocenters, part of which bears a quaternary stereocenter (up to 99 % enantiomeric excess, up to 12.9 : 1 diastereomeric ratio). Detailed mechanistic studies, including computational simulations, uncovered the synergistic effect of the enzyme and the externally added organophotoredox catalyst Rh6G. [ABSTRACT FROM AUTHOR]

Temperature-Cycle-Induced Deracemization (TCID) offers a promising approach to obtain enantiopure solids from racemic mixtures. By combining rapid racemization in solution and temperature swings, homochirality is theoretically achieved. Despite theoretical expectations of doubled yields compared to traditional chiral separation methods, such as in Preferential Crystallization, experimental validation remains lacking. We applied TCID to (1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pentan-3-one) (Cl-TAK), introducing a post-TCID cooling step to enhance yield and a washing step to augment enantiopurity. This refinement yielded an 89.8% mass yield with 99.1% enantiomeric excess in the crystal phase (c.e.e.) within 24 h on an 8.75 g scale, showcasing improved performance with insignificant process duration extension. Additionally, we explored the stochasticity of deracemization, observing the development from low initial crystal enantiomeric excesses (1–6% c.e.e0) at a 2.5 g scale. Kinetic analysis revealed that a 2% c.e.e0 effectively mitigates chiral flipping risks and induction time in our system. Our study underscores the potential for reduced initial c.e.e. to expedite deracemization and presents a straightforward method to optimize yield and purity, facilitating industrial application. [ABSTRACT FROM AUTHOR]

Chiral heterocyclic compounds play a crucial role in the pharmaceutical science, materials science, and agrochemical industries. The critical step for synthesizing chiral heterocycles is the formation of asymmetric carbon‐heteroatom bonds, which can be achieved in a chiral environment under thermal or photochemical conditions. However, photochemical asymmetric transformation has become an area of immense growth in the past 15 years. In the drug discovery and development era, chiral photochemical transformations have drawn the attention of researchers to develop new synthetic strategies for chiral heterocycles via asymmetric carbon‐heteroatom bond formation. Chiral photochemistry in the pathway of asymmetric synthesis requires a chirality source which is transferred to the products. A catalytic chiral metal complexing agent or a chiral photosensitizer that generally follows a single electron transfer (SET) or oxidative and reductive quenching cycle has been widely exploited to achieve this goal. In this review, we have demonstrated the recent development of photochemical synthesis of chiral heterocycles via asymmetric carbon‐heteroatom bond formation by using a chiral metal catalyst, asymmetric organocatalyst, or dual catalytic system based on their plausible mechanism. [ABSTRACT FROM AUTHOR]

This article discusses the development of chiral bifunctional NHC-guanidine ligands for asymmetric hydrogenation. The researchers have shown that these ligands can control chemoselectivity in catalytic reactions, allowing for the reduction of esters to alcohols. They have also synthesized chiral bifunctional ligand precursors using commercially available chiral building blocks. These ligands have been tested in the asymmetric copper(I)-catalyzed hydrogenation of acetophenone, demonstrating the potential for stereoinduction. The results suggest that these ligands could have broader applications in asymmetric catalysis. [Extracted from the article]

Different approaches to achieve 2D supramolecular polymers, as an alternative to the covalent bottom‐up approaches reported for the preparation of 2D materials, are reviewed. The significance of the operation of weak non‐covalent forces to induce a lateral growth of a number of self‐assembling units is collected. The examples of both thermodynamically and kinetically controlled formation of 2D supramolecular polymers showed in this review demonstrate the utility of this strategy to achieve new 2D materials with biased morphologies (nanosheets, scrolls, porous surfaces) and showing elegant applications like chiral recognition, enantioselective uptake or asymmetric organic transformations. Furthermore, elaborated techniques like seeded or living supramolecular polymerizations have been demonstrated to give rise to complex 2D nanostructures. [ABSTRACT FROM AUTHOR]

The document is a corrigendum for a research article titled "Chiral Ligand-Concentration Mediating Asymmetric Transformations of Silver Nanoclusters: NIR-II Circularly Polarized Phosphorescence Lighting." It corrects errors in the presentation of CD curves, anisotropy factors, and concentrations of silver nanoclusters. The revised figures and spectra in the Supporting Information address mislabeling and incorrect structural formulas. The authors assure that the conclusions of the original research article remain unaffected by these errors. [Extracted from the article]

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]

A novel one‐pot deracemization method using a bifunctional chiral agent (BCA) is proposed for the first time to convert a racemate to the desired enantiomer. Specifically, chiral α, (α‐diphenyl‐2‐pyrrolidinemethanol) formed enantiospecific cocrystals with racemic dihydromyricetin, and used its own alkaline catalysis to catalyze the racemization between the (2R,3R)‐enantiomer and (2S,3S)‐enantiomer in solution, achieving a one‐pot spontaneous deracemization. This strategy was also successfully extended to the deracemization of three other racemic compound drugs: (R,S)‐carprofen, (R,S)‐indoprofen, and (R,S)‐indobufen. The one‐pot deracemization method based on the BCA strategy provides a feasible approach to address the incompatibility between cocrystallization and racemization reactions that are commonly encountered in the cocrystallization‐induced deracemization process and opens a new window to develop essential enantiomerically pure pharmaceutical products with atom economy. [ABSTRACT FROM AUTHOR]

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

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

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

This article presents a new experimental protocol for benchmarking the reactivity of chiral catalysts in asymmetric catalysis. The protocol involves comparing the performance of a benchmarking catalyst to that of a structurally dissimilar catalyst in a single competition experiment. The authors validated this approach using N-heterocyclic carbenes (NHCs) as organocatalysts and phosphoramidites as chiral ligands for transition-metal catalysis. The results demonstrate the usefulness of this protocol in understanding the relationship between catalyst structure and reactivity in asymmetric catalysis. The article also pays tribute to Keith Fagnou, a respected colleague. [Extracted from the article]

Asymmetric mechanical transducers have important applications in energy harvesting, signal transmission, and micro-mechanics. To achieve asymmetric transformation of mechanical motion or energy, active robotic metamaterials, as well as materials with asymmetric microstructures or internal orientation, are usually employed. However, these strategies usually require continuous energy supplement and laborious fabrication, and limited transformation modes are achieved. Herein, utilizing wettability patterned surfaces for precise control of the droplet contact line and inner flow, we demonstrate a droplet-based mechanical transducer system, and achieve multimodal responses to specific vibrations. By virtue of the synergistic effect of surface tension and solid-liquid adhesion on the liquid dynamics, the droplet on the patterned substrate can exhibit symmetric/asymmetric vibration transformation when the substrate vibrates horizontally. Based on this, we construct arrayed patterns with distinct arrangements on the substrate, and employ the swarm effect of the arrayed droplets to achieve three-dimensional and multimodal actuation of the target plate under a fixed input vibration. Further, we demonstrate the utilization of the mechanical transducers for vibration management, object transport, and laser modulation. These findings provide a simple yet efficient strategy to realize a multimodal mechanical transducer, which shows significant potential for aseismic design, optical molding, as well as micro-electromechanical systems (MEMS). Asymmetric mechanical transducers are pivotal in various applications; however, conventional methods demand continuous energy and intricate fabrication. Here, the authors demonstrate a droplet-based mechanical transducer utilizing wettability-patterned surfaces, enabling precise control of droplet dynamics. [ABSTRACT FROM AUTHOR]

Asymmetric catalytic carbene reactions have been well documented in the last few decades for the expeditious assembly of chiral molecules with structural diversity. However, the enantioselective construction of all‐carbon quaternary centers remains a challenge in this area. In this review article, two types of asymmetric carbene reactions that beyond cyclopropanation, cyclopropenation, and Büchner reaction, have been summarized for the construction of all‐carbon quaternary centers: 1) using carbene species as a 1C synthon that reacts with a trisubstituted prochiral center; 2) sequential installation of two different C−C bonds on the carbene position, which features a gem‐difunctionalization reaction. Especially, the asymmetric metal carbene gem‐dialkylation process, which has emerged as a practical and versatile method for the expeditious assembly of complex architectures from readily available chemical resources, is a complementary approach for the expeditious assembly of all‐carbon quaternary centers. [ABSTRACT FROM AUTHOR]