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Vicinal stereogenic centers represent prevalent structural motifs in organic synthetic chemistry, and their construction poses a longstanding challenge. Transition-metal-catalyzed asymmetric allylic substitution has become a well-established enantioselective C–C bond-forming reaction. When these reactions involve a prochiral nucleophile and an allylic electrophile with a terminal substituent, the creation of vicinal stereogenic centers becomes feasible. However, despite remarkable achievements having been accomplished, realizing this transformation with precise control over both the enantio- and diastereoselectivity remains a significant challenge. To address the stereoselective challenges, the introduction of a second catalyst to the transition-metal-catalyzed asymmetric allylic alkylation to control the diastereoselectivity during C–C bond formation has proven particularly fruitful. In this short review, we aim to highlight recent advances in dual catalysis that enable diastereo- and enantioselective allylic substitutions. 1 Introduction 2 Construction of Vicinal Stereogenic Centers by Organo and Metal Dual Catalysis 2.1 Chiral Phase-Transfer Catalysis and Transition-Metal Dual Catalysis 2.2 Chiral Amine and Transition-Metal Dual Catalysis 2.3 NHC and Transition-Metal Dual Catalysis 2.4 Chiral Aldehyde and Transition-Metal Dual Catalysis 2.5 Chiral Lewis Base and Transition-Metal Dual Catalysis 3 Construction of Vicinal Stereogenic Centers by Metal and Metal Dual Catalysis 3.1 Lewis Acidic Metal and Iridium Dual Catalysis 3.2 Lewis Acidic Metal and Palladium Dual Catalysis 3.3 Palladium and Ruthenium Dual Catalysis 3.4 Other Advancements in the Construction of Vicinal Stereogenic Centers through Synergistic Bimetallic Catalysis Enabling Asymmetric Allylic Alkylation 4 Conclusions and Future Outlook [ABSTRACT FROM AUTHOR]

Nickel catalysis is a well-established and powerful tool for C–C cross-coupling reactions, and its versatility has expanded significantly over past decades by its combination with visible-light photocatalysis in metallaphotoredox chemistry. Photocatalysis enables the activation of traditionally inert substrates and turnover of the Ni catalyst through a single-electron transfer processes. In recent years, dual catalysis has been further empowered by photoactive Ni intermediates, which exhibit distinct reactivity profiles from their ground states and complement existing protocols. This short review focuses on the emergent subclass of metallaphotoredox catalysis in which the synergy of a photoactive Ni catalyst and a typical photocatalyst (e.g., a polypyridyl Ir complex) provide solutions to challenging C–C bond formation. 1 Introduction 2 Photoactive Nickel Complexes 3 HAT-Mediated C–C Cross-Coupling 4 Halofunctionalization of π-Systems 5 Photoelimination of an Aryl Radical 6 Conclusion [ABSTRACT FROM AUTHOR]

The first stereodivergent umpolung 1,5-conjugate addition reaction via synergistic Pd/Cu catalysts is reported. By dictating the absolute configuration of each chiral ligand ligated to corresponding metals, all four stereoisomers of the products are easily achieved. A series of amino acid moieties are introduced to the γ-position of the conjugated esters in high yields with excellent diastereoselectivities and enantioselectivities. The downstream transformations highlight the synthetic value of the method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combining tetragonal BTO nanoparticles and 2D MXene nanosheets creates BTO-MX, which can degrade 90 % of RhB in 15 min. • MXene nanosheets enhance electrical conductivity and energy conversion rate during advanced oxidation process. • The heterogeneous structure of BTO-MX provides sufficient active sites, aiding in the adsorption and degradation of RhB. • The synergistically piezo-photocatalytic properties enabled by efficient carrier generation and separation in BTO-MX. Piezo-photocatalysis combines photocatalysis and piezoelectric effects to enhance catalytic efficiency by creating an internal electric field in the photocatalyst, improving carrier separation and overall performance. This study presents a high-performance piezo-photocatalyst for efficient dye degradation using a synergistic barium titanate (BTO)-MXene composite. The composite was synthesized via a facile method, combining the unique properties of BTO nanoparticles with the high conductivity of MXene. The structural and morphological analysis confirmed the successful formation of the composite, with well-dispersed BTO nanoparticles on the MXene surface. The piezo-photocatalytic activity of the composite was evaluated using a typical dye solution (Rhodamine B: RhB) under ultraviolet irradiation and mechanical agitation. The results revealed a remarkable enhancement in dye degradation (90 % in 15 min for piezo-photocatalysis) compared to individual stimuli (58.2 % for photocatalysis and 95.8 % in 90 min for piezocatalysis), highlighting the synergistic effects between BTO and MXene. The enhanced catalytic performance was attributed to the efficient charge separation and transfer facilitated by the composite's structure, leading to increased reactive species generation and dye molecule degradation. Furthermore, the composite exhibited excellent stability and reusability, showcasing its potential for practical applications in wastewater treatment. Overall, this work represents a promising strategy for designing high-performance synergistic catalysts, addressing the pressing need for sustainable solutions in environmental remediation. [ABSTRACT FROM AUTHOR]

Incorporation of CO into substrates to construct high‐value carbonyl compounds is an intensive industrial carbonylation procedure, however, high toxicity and wide explosion limits (12.5–74.0 vol% in air) of CO limit its application in industrial production. The development of a CO‐free catalytic system for carbonylation is one of ideal methods, but full of challenge. Herein, this study reports the CO‐free aminocarbonylation conversion of terminal alkynes synergistically catalyzed by a unique Co(ІІ)/Ag(І) metal–organic framework (MOF), in which the combination of isocyanides and O2 is employed as safe and green source of aminocarbonyl. This reaction has broad substrate applicability in terminal alkyne and isocyanides components with 100% atom economy. The bimetal MOF catalyst can be recycled at least five times without substantial loss of catalytic activities. Mechanistic investigations demonstrate that the synergistic effect between Ag(I) and Co(II) sites can efficiently activate terminal alkyne and isocyanides, respectively. Free radical capture experiments, FT‐IR analysis and theoretical explorations further reveal that terminal alkynes and isocyanides can be catalytically transformed into an anionic intermediate through heterolysis pathways. This work provides secure and practical access to carbonylation as well as a new approach to aminocarbonylation of terminal alkynes. [ABSTRACT FROM AUTHOR]

The efficient construction of chalcogen‐atom‐based chiral compounds remains a challenge, despite the importance of organoselenium and organosulfur compounds in life and materials science. Chalcogen atoms can form net attractive interactions called chalcogen bonds, but it is an undeveloped tool to assist asymmetric catalysis. Herein, we report an enantioselective insertion platform to install a stereogenic center bearing selenyl and thiocyano functional groups. Our method operates by synergistic catalysis by a chiral guanidine and an achiral dirhodium complex in a three‐component or four‐component reaction, through Se−S bond insertion into carbene species, competing successfully with the spontaneous racemic process and showing high regioselectivity. As elucidated by spectroscopic experiments and computational studies, a unique mechanism involving chalcogen as well as hydrogen bonding was established to account for the enantiocontrol. The high stereoselectivity holds for a broad array of selenylthiocyanatopropanoates, which showed excellent anti‐inflammatory toward IL‐1β and low cytotoxicity. [ABSTRACT FROM AUTHOR]

The development of efficient methodologies for the controlled manufacture of specific stereoisomers bearing quaternary stereocenters has prompted advances in a variety of scientific disciplines including pharmaceutical chemistry, materials science, and chemical biology. However, complete control of the absolute and relative stereochemical configurations of alkyne derivatives remains an unmet synthetic challenge. Herein, a Ni/Cu dual‐catalyzed asymmetric propargylic substitution reaction is presented to produce propargylated products with all‐carbon quaternary stereocenters in high yields with significant diastereo‐ and enantioselectivities (up to >20:1 dr, >99% ee). The synthesis of all stereochemical variants of methohexital, a widely used sedative‐hypnotic drug, exemplifies the efficacy of dual‐catalyzed stereodivergent propargylation. [ABSTRACT FROM AUTHOR]

Natural photosynthesis enzymes utilize energies of several photons for challenging oxidation of water, whereas artificial photo‐catalysis typically involves only single‐photon excitation. Herein, a multiphoton excitation strategy is reported that combines parallel photo‐excitations with a photoinduced electron transfer process for the activation of C(sp3)─H bonds, including methane. The metal–organic framework Fe3‐MOF is designed to consolidate 4,4′,4″‐nitrilotrisbenzoic units for the photoactivation of dioxygen and trinuclear iron clusters as the HAT precursor for photoactivating alkanes. Under visible light irradiation, the dyes and iron clusters absorbed parallel photons simultaneously to reach their excited states, respectively, generating 1O2 via energy transfer and chlorine radical via ligand‐to‐metal charge transfer. The further excitation of organic dyes leads to the reduction of 1O2 into O2•− through a photoinduced electron transfer, guaranteeing an extra multiphoton oxygen activation manner. The chlorine radical abstracts a hydrogen atom from alkanes, generating the carbon radical for further oxidation transformation. Accordingly, the total oxidation conversion of alkane utilizing three photoexcitation processes combines the energies of more than two photons. This new platform synergistically combines a consecutive excited photoredox organic dye and a HAT catalyst to combine the energies of more than two photons, providing a promising multiphoton catalysis strategy under energy saving, and high efficiency. [ABSTRACT FROM AUTHOR]

Precisely controlling the product selectivity of a reaction is an important objective in organic synthesis. α‐Ketoamides are vital intermediates in chemical transformations and privileged motifs in numerous drugs, natural products, and biologically active molecules. The selective synthesis of α‐ketoamides from feedstock chemicals in a safe and operationally simple manner under mild conditions is a long‐standing catalysis challenge. Herein, an unprecedented TBD‐switched Pd‐catalyzed double isocyanide insertion reaction for assembling ketoamides in aqueous DMSO from (hetero)aryl halides and pseudohalides under mild conditions is reported. The effectiveness and utility of this protocol are demonstrated by its diverse substrate scope (93 examples), the ability to late‐stage modify pharmaceuticals, scalability to large‐scale synthesis, and the synthesis of pharmaceutically active molecules. Mechanistic studies indicate that TBD is a key ligand that modulates the Pd‐catalyzed double isocyanide insertion process, thereby selectively providing the desired α‐ketoamides in a unique manner. In addition, the imidoylpalladium(II) complex and α‐ketoimine amide are successfully isolated and determined by X‐ray analysis, confirming that they are probable intermediates in the catalytic pathway. [ABSTRACT FROM AUTHOR]

• Ca-based, non-Ca-based additives and recycled solid wastes reduce PI and enhance TD. • These active ingredients improve soil texture via cation exchange and flocculation. • Transition metal oxides catalyze TD of nonchlorinated POPs via two mechanisms. • We also reviewed alkali, solid wastes and nano metals as catalysts to enhance TD. • Additives in photo- and photo-thermal-catalysis and their mechanisms are reviewed. High temperatures and providing sufficient time for the thermal desorption of persistent organic pollutants (POPs) from contaminated clay soils can lead to intensive energy consumption. Therefore, this article provides a critical review of the potential additives which can improve soil texture and increase the volatility of POPs, and then discusses their enhanced mechanisms for contributing to a green economy. Ca-based additives have been used to reduce plasticity of bentonite clay, absorb water and replenish system heat. In contrast, non-Ca-based additives have been used to decrease the plasticity of kaolin clay. The soil structure and soil plasticity can be changed through cation exchange and flocculation processes. The transition metal oxides and alkali metal oxides can be applied to catalyze and oxidize polycyclic aromatic hydrocarbons, petroleum and emerging contaminants. In this system, reactive oxygen species (•O 2 − and •OH) are generated from thermal excitation without strong chemical oxidants. Moreover, multiple active ingredients in recycled solid wastes can be controlled to reduce soil plasticity and enhance thermal catalysis. Alternatively, the alkali, nano zero-valent iron and nano-TiN can catalyze hydrodechlorination of POPs under reductive conditions. Especially, photo and photo-thermal catalysis are discussed to accelerate replacement of fossil fuels by renewable energy in thermal remediation. [Display omitted] [ABSTRACT FROM AUTHOR]

A large amount of toxic smoke and heat generated by the combustion of ethylene vinyl acetate copolymer (EVA) poses a significant threat to human fire escape evacuation. This work aims to use γ -ray to prepare e-MXene@Ag hybrid flame-retardant materials by the method of in-situ reduction, and EVA composites are prepared by melt blending to reduce the smoke and toxic gases produced during combustion significantly. Compared with pure EVA, the total heat release, total smoke release, and the production rate of CO and CO2 produced by the combustion of EVA composite with 1 wt% e-MXene@Ag1.0 decreased by 30.3%, 33.3%, 18.2%, and 20.1% respectively. The fire hazard reduction of EVA composite materials was due to the physical barrier, catalytic carbonization and adsorption of the e-MXene@Ag1.0 hybrid. In addition, e-MXene@Ag1.0 can also further increase the mechanical properties of EVA composites due to its own 'multi-contact point limit structure'. [ABSTRACT FROM AUTHOR]

Intermolecular pnictogen bonding (PnB) catalysis has received increased interest in non‐covalent organocatalysis. It has been demonstrated that organic electron‐deficient pnictogen atoms can act as prospective Lewis acids. Here, we present a catalytic approach for the asymmetric synthesis of chiral PIII compounds by combining intramolecular PnB interactions and carbene catalysis. Our design features a pre‐chiral phosphorus molecule bearing two electron‐withdrawing benzoyl groups, resulting in the formation of a σ‐hole at the P atom. X‐ray and non‐covalent interaction (NCI) analysis indicate that the model substrates exhibit intrinsic PnB interaction between the oxygen atom of the formyl group and the phosphorus atom. This induces a conformational locking effect, leading to the crystallization of the phosphorus substrate in a preferred conformation (P212121 chiral group). Under the catalysis of N–heterocyclic carbene, the aldehyde moiety activated by the pnictogen bond selectively reacts with an alcohol to yield the corresponding chiral monoester/phosphorus product with excellent enantioselectivity. This Lewis acidic phosphorus center, aroused by the non‐polarized intramolecular pnictogen bond interaction, assists in conformational and selective regulations, providing unique opportunities for catalysis and beyond. [ABSTRACT FROM AUTHOR]

Recent interest has surged in using heterogeneous carriers to boost synergistic photocatalysis for organic transformations. Heterogeneous catalysts not only facilitate synergistic enhancement of distinct catalytic centers compared to their homogeneous counterparts, but also allow for the easy recovery and reuse of catalysts. This mini‐review summarizes recent advancements in developing heterogeneous carriers, including metal–organic frameworks, covalent–organic frameworks, porous organic polymers, and others, for synergistic catalytic reactions. The advantages of porous materials in heterogeneous catalysis originate from their ability to provide a high surface area, facilitate enhanced mass transport, offer a tunable chemical structure, ensure the stability of active species, and enable easy recovery and reuse of catalysts. Both photosensitizers and catalysts can be intricately incorporated into suitable porous carriers to create heterogeneous dual photocatalysts for organic transformations. Notably, experimental evidence from reported cases has shown that the catalytic efficacy of heterogeneous catalysts often surpasses that of their homogeneous analogues. This enhanced performance is attributed to the proximity and confinement effects provided by the porous nature of the carriers. It is expected that porous carriers will provide a versatile platform for integrating diverse catalysts, thus exhibiting superior performance across a range of organic transformations and appealing prospect for industrial applications. [ABSTRACT FROM AUTHOR]

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon molecules. Herein, we reported the precise immobilization of metal single atoms (M-SAs; M = Ru, Rh, Ir, Pd, Pt, and Au) into a porphyrinic metal-organic framework (MOF) of PCN-222 (PCN = porous coordination network), and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene hydrosilylation. Under solvent-free conditions, Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room temperature. Experimental and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates, which helped to condense the substrates in the cavities of the porous catalysts. Further density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway. [ABSTRACT FROM AUTHOR]

Enzymes have flexible structures and can modulate the multiple catalytic sites efficiently for synergistic catalysis. Inspired by enzymes, various artificial catalysts have been designed, while controllable synergistic effects in artificial catalysts have never been reported. Here, we report the first example of photo‐regulated synergistic catalyst (PRSC) and the synergistic effects between acidic and basic sites can be regulated by light. PRSCs have acidic sites on pore walls and basic sites on pendant azobenzene groups, and photo‐regulation is achieved through azobenzene isomerization. In the cascade reaction of converting benzaldehyde dimethyl acetal (BA) to benzylidenemalononitrile (BM), the PRSC shows a change of up to 33.6% in BM yield. Mechanism exploration indicates that cis azobenzene makes the catalytic system more stable. The promoted adsorption energy of the reactant malononitrile (MN) on basic sites and the activated C atom of MN that connects to methylene groups are responsible for the tunable synergistic effects of PRSCs. [ABSTRACT FROM AUTHOR]

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading, adjustable active centres, and electronic valence states. However, the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory stage. Here, we designed and synthesized a bimetallic palladium complex (BPB-Pd2) with conjugated backbone. The supported BPB-Pd2 was applied to electrochemical CO2 reduction reaction (CO2RR) for the first time. The as-obtained BPB-Pd2 gives an exceptional Faradaic efficiency of CO (FECO) of 94.4% at −0.80 V vs. reversible hydrogen electrode (RHE), which is significantly superior to monoatomic palladium catalyst (BPB-Pd1). The density functional theory (DFT) calculations revealed that the essential reason for the outstanding activity of BPB-Pd2 toward CO2RR was that the electronic effect between diatomic palladium reduces the free energy change for CO2RR process. Thus, BPB-Pd2 exhibits moderate free energy change to form COOH* intermediate, which was beneficial for the generation of CO in CO2RR. [ABSTRACT FROM AUTHOR]

Abstract Incorporation of CO into substrates to construct high‐value carbonyl compounds is an intensive industrial carbonylation procedure, however, high toxicity and wide explosion limits (12.5–74.0 vol% in air) of CO limit its application in industrial production. The development of a CO‐free catalytic system for carbonylation is one of ideal methods, but full of challenge. Herein, this study reports the CO‐free aminocarbonylation conversion of terminal alkynes synergistically catalyzed by a unique Co(ІІ)/Ag(І) metal–organic framework (MOF), in which the combination of isocyanides and O2 is employed as safe and green source of aminocarbonyl. This reaction has broad substrate applicability in terminal alkyne and isocyanides components with 100% atom economy. The bimetal MOF catalyst can be recycled at least five times without substantial loss of catalytic activities. Mechanistic investigations demonstrate that the synergistic effect between Ag(I) and Co(II) sites can efficiently activate terminal alkyne and isocyanides, respectively. Free radical capture experiments, FT‐IR analysis and theoretical explorations further reveal that terminal alkynes and isocyanides can be catalytically transformed into an anionic intermediate through heterolysis pathways. This work provides secure and practical access to carbonylation as well as a new approach to aminocarbonylation of terminal alkynes.

Abstract Precisely controlling the product selectivity of a reaction is an important objective in organic synthesis. α‐Ketoamides are vital intermediates in chemical transformations and privileged motifs in numerous drugs, natural products, and biologically active molecules. The selective synthesis of α‐ketoamides from feedstock chemicals in a safe and operationally simple manner under mild conditions is a long‐standing catalysis challenge. Herein, an unprecedented TBD‐switched Pd‐catalyzed double isocyanide insertion reaction for assembling ketoamides in aqueous DMSO from (hetero)aryl halides and pseudohalides under mild conditions is reported. The effectiveness and utility of this protocol are demonstrated by its diverse substrate scope (93 examples), the ability to late‐stage modify pharmaceuticals, scalability to large‐scale synthesis, and the synthesis of pharmaceutically active molecules. Mechanistic studies indicate that TBD is a key ligand that modulates the Pd‐catalyzed double isocyanide insertion process, thereby selectively providing the desired α‐ketoamides in a unique manner. In addition, the imidoylpalladium(II) complex and α‐ketoimine amide are successfully isolated and determined by X‐ray analysis, confirming that they are probable intermediates in the catalytic pathway.

Abstract The development of efficient methodologies for the controlled manufacture of specific stereoisomers bearing quaternary stereocenters has prompted advances in a variety of scientific disciplines including pharmaceutical chemistry, materials science, and chemical biology. However, complete control of the absolute and relative stereochemical configurations of alkyne derivatives remains an unmet synthetic challenge. Herein, a Ni/Cu dual‐catalyzed asymmetric propargylic substitution reaction is presented to produce propargylated products with all‐carbon quaternary stereocenters in high yields with significant diastereo‐ and enantioselectivities (up to >20:1 dr, >99% ee). The synthesis of all stereochemical variants of methohexital, a widely used sedative‐hypnotic drug, exemplifies the efficacy of dual‐catalyzed stereodivergent propargylation.

Abstract Natural photosynthesis enzymes utilize energies of several photons for challenging oxidation of water, whereas artificial photo‐catalysis typically involves only single‐photon excitation. Herein, a multiphoton excitation strategy is reported that combines parallel photo‐excitations with a photoinduced electron transfer process for the activation of C(sp3)─H bonds, including methane. The metal–organic framework Fe3‐MOF is designed to consolidate 4,4′,4″‐nitrilotrisbenzoic units for the photoactivation of dioxygen and trinuclear iron clusters as the HAT precursor for photoactivating alkanes. Under visible light irradiation, the dyes and iron clusters absorbed parallel photons simultaneously to reach their excited states, respectively, generating 1O2 via energy transfer and chlorine radical via ligand‐to‐metal charge transfer. The further excitation of organic dyes leads to the reduction of 1O2 into O2•− through a photoinduced electron transfer, guaranteeing an extra multiphoton oxygen activation manner. The chlorine radical abstracts a hydrogen atom from alkanes, generating the carbon radical for further oxidation transformation. Accordingly, the total oxidation conversion of alkane utilizing three photoexcitation processes combines the energies of more than two photons. This new platform synergistically combines a consecutive excited photoredox organic dye and a HAT catalyst to combine the energies of more than two photons, providing a promising multiphoton catalysis strategy under energy saving, and high efficiency.

An unusual diastereodivergent stereoselective allylation reaction is presented. It consists of a palladium-catalyzed allylation reaction of an organocatalytically generated amino isobenzofulvene, where the diastereoselectivity is controlled by the electronic properties of a monodentate, achiral ligand on palladium. One major diastereoisomer is formed using triarylphosphines substituted with neutral or electron-donating substituents of the aryl group, while those with electron-withdrawing substituents favor the other diastereoisomer. The diastereoselectivity correlates with the Taft inductive parameter of substituents on the triarylphosphine ligand on palladium. The synergistic reaction involves both a catalytic secondary amine catalyst for the indene-aldehyde activation and the monodentate phosphine ligands on palladium, affording a highly enantioselective reaction with up to 98 % enantiomeric excess. Based on computational investigations, the role of the monodentate phosphine ligand on the diastereoselectivity is discussed.

The construction of two distal stereocenters through a single catalytic process is of great interest in organic synthesis. While there are some successful reports regarding stereodivergent preparation of 1,3‐ or 1,4‐stereocenters, the more challenged 1,5‐nonadjacent stereocenters have never been achieved in a stereodivergent fashion. Herein we describe a synergistic palladium/copper catalysis for 1,4‐difunctionalization reactions of 1,3‐dienes, providing access to 1,5‐nonadjacent quaternary stereocenters. Because each of the two catalysts separately controlled one of the newly formed stereocenters, stereodivergent synthesis of all four diastereomers of the products could readily be achieved simply by choosing an appropriate combination of chiral catalysts. Experimental and computational studies supported a mechanism involving a Heck/Tsuji–Trost cascade reaction, and the origins of the stereoselectivity were elucidated. [ABSTRACT FROM AUTHOR]

Catalytic hydrogenation of nitroarenes is a type of important reaction to get corresponding amines, the development of catalysts with outstanding catalytic performance is in urgent need. In this review, we summarize the breakthroughs in the development of supported metal catalysts in the past few decades, including the use of different metals and supports, improved metal utilization efficiency, adjustment of the structure, and the interaction. We focus on how to develop and innovate the structure of the catalyst, aiming at the contradiction between conversion and selectivity in selective hydrogenation of nitroarenes, from the perspective of the structure and the interaction to construct a kind of catalyst with low noble metal loading and high activity, stabilize the active components, and design and fabricate hybrid nanostructured catalysts with desired activity and selectivity. The development process and the catalytic performance of metal‐2D semiconductor hybrid nano‐structure catalyst are also discussed and provide a theoretical and practical basis for the precise design of supported metal catalysts. [ABSTRACT FROM AUTHOR]

The reaction kinetics of photocatalytic CO2 reduction is highly dependent on the transfer rate of electrons and protons to the CO2 molecules adsorbed on catalytic centers. Studies on uncovering the proton effect in catalysts on photocatalytic activity of CO2 reduction are significant but rarely reported. In this paper, we, from the molecular level, revealed that the photocatalytic activity of CO2 reduction is closely related to the proton availability in catalysts. Specifically, four dinuclear Co(II) complexes based on Robson-type ligands with different number of carboxylic groups (-nCOOH; n = 0, 2, 4, 6) were designed and synthesized. All these complexes show photocatalytic activity for CO2 reduction to CO in a water-containing system upon visible-light illumination. Interestingly, the CO yields increase positively with the increase of the carboxylic-group number in dinuclear Co(II) complexes. The one containing -6COOH shows the best photocatalytic activity for CO2 reduction to CO, with the TON value reaching as high as 10,294. The value is 1.8, 3.4, and 7.8 times higher than those containing -4COOH, -2COOH, and -0COOH, respectively. The high TON value also makes the dinuclear Co(II) complex with -6COOH outstanding among reported homogeneous molecular catalysts for photocatalytic CO2 reduction. Control experiments and density functional theory calculation indicated that more carboxylic groups in the catalyst endow the catalyst with more proton relays, thus accelerating the proton transfer and boosting the photocatalytic CO2 reduction. This study, at a molecular level, elucidates that more carboxylic groups in catalysts are beneficial for boosting the reaction kinetics of photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • The FeCoNiMnV HEA/ N -CNTs catalyst was prepared by a one-step pyrolysis. • The multi-metal synergy favored the ORR catalytic performance. • Clustered N -CNTs had rich shared boundaries and interstitial space to expedite the charge/mass transfer. • The built battery showed high OCV, large power density and long-term durability. Efficient and stable oxygen reduction reaction (ORR) catalysts are essential for constructing reliable energy conversion and storage devices. Herein, we prepared noble metal-free FeCoNiMnV high-entropy alloy supported on nitrogen-doped carbon nanotubes (FeCoNiMnV HEA/ N -CNTs) by a one-step pyrolysis at 800 °C, as certificated by a set of characterizations. The graphitization degree of the N -CHTs was optimized by tuning the pyrolysis temperature in the control groups. The resultant catalyst greatly enhanced the ORR characteristics in the alkaline media, showing the positive onset potential (E onset) of 0.99 V and half-wave potential (E 1/2) of 0.85 V. More importantly, the above FeCoNiMnV HEA/ N -CNTs assembled Zn-air battery exhibited a greater open-circuit voltage (1.482 V), larger power density (185.12 mW cm−2), and outstanding cycle stability (1698 cycles, 566 h). This study provides some valuable insights on developing sustainable ORR catalysts in Zn-air batteries. [ABSTRACT FROM AUTHOR]

Synergistic catalytic effects and metal node modulation are pivotal to the performance of multifunctional catalysts.We present a versatile strategy for constructing bimetallic M1M2 cluster catalysts (polyoxometalates (POMs)/Zr‐based metal‐organic frameworks (Zr‐MOF); M1 = Zr; M2 = W, V, Mo) by a microwave‐assisted in‐situ precoordination‐postmodification approach, which consisted of the grafting of POM single clusters onto Zr–O clusters of hierarchical porous composites (defective Zr‐MOF (HUiO‐66x)) and the modulation of metal nodes in Zr‐MOF. Hierarchical porosity and double active centers in the POMs/Zr‐MOF result in greater accessibility to catalytic sites and adjustable acid–base properties, thus providing opportunities for the catalytic transfer hydrogenation of biomass‐derived aldehydes/ketones. The synergistic acid–base couple sites (W6+–O2−–Zr4+) not only bridge hydrogen donors into the reaction system but also promote the dissociation of α‐C(sp3)‐H from isopropanol and subsequent hydrogen transfer to the activated carbonyl in furfural. Enhanced substrate adsorption and decreased activation barrier of the rate‐determining step are keys for the direct hydrogen transfer from carbonyl compounds to near‐quantitative corresponding alcohols via an eight‐membered‐ring transition state to achieving unprecedented low‐temperature catalytic performance over bimetallic Zr–W clusters. The proposed general method of bimetallic cluster catalysts reveals the roles of accessible metal modulation and synergistic catalytic centers toward specific catalysis. [ABSTRACT FROM AUTHOR]

Mn(I)‐catalyzed enantioselective C−C bond‐forming reactions represent a great challenge in homogeneous catalysis primarily due to a limited understanding of its mechanistic principles. Herein, we have developed an interesting catalytic strategy that leverages a synergistic combination of a dimeric manganese(I) catalyst and a chiral aminocatalyst to address this issue. A range of conjugated dienals and trienals can exclusively proceed 1,4‐hydroalkenylation by using readily available aromatic and aliphatic alkenyl boronic acids as coupling partners, producing a rich library of skipped diene aldehydes in synthetically useful yields and high levels of enantioselectivities. Notably, downstream transformations of these products can not only afford a concise approach to construct enantioenriched skipped trienes but also realize enantioselective total synthesis of analogues to (−)‐Blepharocalyxin D in four steps. DFT calculations suggest the 1,4‐hydroalkenylation is kinetically more favorable than 1,6‐hydroalkenylation. [ABSTRACT FROM AUTHOR]

3,4-Dihydroisoquinoline (DHIQ) is an important precursor used in the production of drugs for treating cancer, HIV, Alzheimer's disease, etc. Major studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of 1,2,3,4-tetrahydroisoquinoline (THIQ), which often requires alkali co-catalysts. Therefore, it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction conditions. Herein, a novel framework 1 was synthesized, exhibiting 1D channels with the size of 4.6 Å × 9.6 Å and high solvent/pH/thermal stability. A stable framework allows it to encapsulate Cu nanoparticles (NPs) to form Cu NPs@1-x (x = 1, 2, 3, and 4) with varying loading amounts of Cu NPs at 2.0 wt%, 3.0 wt%, 4.0 wt%, and 6.0 wt%, respectively. Cu NPs@1–3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98% and a recorded turnover frequency (TOF) of 22.1 h−1 under eco-friendly mild conditions. The corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale experiments. Additionally, the efficient preparation of DHIQ catalyzed by Cu NPs@1–3 could be realized even under air conditions. Importantly, the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@1–3. Mechanism investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal centers. More importantly, this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds. [ABSTRACT FROM AUTHOR]

As a promising candidate for the next generation energy storage system, rechargeable lithium-oxygen batteries (LOBs) still face substantial challenges caused by insulating discharge products that preclude their practical application. Exploring highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance LOBs. Herein, Pd decorated Te nanowires (Pd@Te NWs) were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect, in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ratio. Meanwhile, Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode, enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm−2. Experimental studies and density functional theory (DFT) calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te, in which uniform electron distribution, extensive electron exchange, and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products, while the high adsorption energy of Te substrate for Li species reduces the initial dynamical energy barrier during discharging process. The current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects. [ABSTRACT FROM AUTHOR]

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A synergistic chiral primary amine/palladium /p‐hydroquinone catalysis was developed to facilitate oxidative asymmetric allylic C−H alkylation under aerobic conditions. The ternary synergistic catalysis enables a facile allylic C−H activation and alkylation with oxygen so that stoichiometric utilization of benzoquinone can be avoided. The identified optimal catalytic system allows for terminal addition to allyl arenes with α‐branched β‐ketocarbonyls to afford allylic adducts bearing all‐carbon quaternary centers with high regio‐ and enantioselectivity. This work provides new insights for further studies on the aerobically oxidative C−H alkylation reaction. [ABSTRACT FROM AUTHOR]

A designed Mg88.7Ni6.3Y5 hydrogen storage alloy containing 14H type LPSO (long-period stacking ordered) and ternary eutectic structure was prepared by regulating the alloy composition and casting. The hydrogen storage performance of the alloy was improved by adding nano-flower-like TiO2@C catalyst. The decomposition of the LPSO structure during hydrogenation led to the formation of plenty of nanocrystals which provided abundant interphase boundaries and activation sites. The nanoscale TiO2@C catalyst was uniformly dispersed on the surface of alloy particles, and the ''hydrogen overflow'' effect of TiO2@C accelerated the dissociation and diffusion of hydrogen on the surface of the alloy particles. As a result, the in-situ endogenous nanocrystals of the LPSO structure decomposition and the externally added flower-like TiO2@C catalyst uniformly dispersed on the surface of the nanoparticles played a synergistic catalytic role in improving the hydrogen storage performance of the Mg-based alloy. With the addition of the TiO2@C catalyst, the beginning hydrogen desorption temperature was reduced to 200 °C. Furthermore, the saturated hydrogen absorption capacity of the sample was 5.32 wt.%, and it reached 4.25 wt.% H2 in 1 min at 200 °C and 30 bar.

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically important α-fluoro γ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric hindrance. Herein, a novel asymmetric [3+2] annulation of α-fluoro α-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization, affording a variety of enantioenriched α-fluoro γ-butyrolactones bearing vicinal stereogenic centers with high reaction efficiency and excellent levels of both stereoselectivity and regioselectivity (up to 98% yield, generally >20:1 dr and >99% ee). Notably, all four stereoisomers of these pharmaceutically valuable molecules could be accessed individually via simple permutations of two enantiomeric catalysts. In addition, other azaaryl acetates bearing α-methyl, α-chlorine or α-phenyl group were tolerated well in this transformation. Reaction mechanistic investigations were conducted to explore the process of this bimetallic catalysis based on the results of reaction intermediates, isotopic labelling experiments, and kinetic studies.

Zirconium/Hafnium-oxo clusters (Zr 9 -TC4A and Hf 9 -TC4A) modified by hydrophobic 4- tert -butylthiacalix[4]arene (H 4 TC4A) ligands were synthesized for the first time, in which unsaturated coordinated sulfur (S) atoms on the TC4A4− ligand can generate strong metal–ligand synergy with nearby active metal Zr/Hf sites. The synergistic effect between metals and ligands resulted in excellent catalytic performance when Zr 9 -TC4A and Hf 9 -TC4A were used as bifunctional catalysts for amine oxidation reactions. [Display omitted] The performance applications (e.g., photocatalysis) of zirconium (Zr) and hafnium (Hf) based complexes are greatly hindered by the limited development of their structures and the relatively inert metal reactivity. In this work, we constructed two ultrastable Zr/Hf-based clusters (Zr 9 -TC4A and Hf 9 -TC4A) using hydrophobic 4- tert -butylthiacalix[4]arene (H 4 TC4A) ligands, in which unsaturated coordinated sulfur (S) atoms on the TC4A4− ligand can generate strong metal–ligand synergy with nearby active metal Zr/Hf sites. As a result, these two functionalized H 4 TC4A ligands modified Zr/Hf-oxo clusters, as catalysts for the amine oxidation reaction, exhibited excellent catalytic activity, achieving very high substrate conversion (>99%) and product selectivity (>90%). Combining comparative experiments and theoretical calculations, we found that these Zr/Hf-based cluster catalysts accomplish efficient amine oxidation reactions through synergistic effect between metals and ligands: (i) The photocatalytic benzylamine (BA) oxidation reaction was achieved by the synergistic effect of the dual active sites, in which, the naked S sites on the TC4A4− ligand oxidize the BA by photogenerated hole and oxygen molecules are reduced by photogenerated electrons on the metal active sites; (ii) in the aniline oxidation reaction, aniline was adsorbed by the bare S sites on ligands to be closer to metal active sites and then oxidized by the oxygen-containing radicals activated by the metal sites, thus completing the catalytic reaction under the synergistic catalytic effect of the proximity metal–ligand. In this work, the Zr/Hf-based complexes applied in the oxidation of organic amines have been realized using active S atom-directed metal–ligand synergistic catalysis and have demonstrated very high reactivity. [ABSTRACT FROM AUTHOR]

The combination of organocatalytic activation and photocatalysis for enabling the intramolecular [2+2]‐cycloaddition of enone‐ene substrates bearing one Lewis base binding site is reported. While in a variety of solvents a poor conversion or no reaction takes place in the absence of a hydrogen bonding catalyst, the corresponding ring‐fused cyclobutane products could be built in moderate to good yields using a synergistic dual iridium‐urea co‐catalytic system. Control and mechanistic studies supported the postulated interaction between the organocatalyst and the substrate, which proved essential for an efficient energy transfer from the photosensitizer. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In this paper, we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines. The protocol is performed at mild conditions without the use of noble metals as catalysts. A wide range of structurally diverse secondary amines could be obtained in good yields (up to 94%) with good functional group tolerance. This transformation shows good to excellent selectivity, avoiding the generation of over alkylated byproducts. [ABSTRACT FROM AUTHOR]

Magnesium hydride (MgH 2) stands out as a promising solid-state material for high-density hydrogen storage, offering enormous potential for applications in hydrogen transportation and storage. However, the stable thermodynamics and sluggish kinetics of dehydrogenation/hydrogenation of MgH 2 impede its practical use in on-board hydrogen storage. In this study, the nanocomposite of nickel/manganese oxide (Ni/MnO) was successfully synthesized through the hydrogenation of nickel-manganese two-dimensional layered double hydroxide (NiMn-LDH) and then introduced into MgH 2 by ball milling to form BM-MgH 2 -Ni/MnO composite. Notably, BM-MgH 2 -Ni/MnO-10 displayed excellent hydrogen absorption/dehydrogenation properties. For example, its onset hydrogen release temperature was remarkably reduced to 175.6 °C, 84 °C lower than that of BM-MgH 2. At a temperature of 250 °C, it could desorb about 6.2 wt% of H 2 within 60 min. The fully dehydrogenated product could absorb 5.5 wt% of H 2 within 10 min at 150 °C. Moreover, BM-MgH 2 -Ni/MnO-10 exhibited excellent cycling performance. Throughout the cycling process, the in-situ formation of Mg 2 Ni/Mg 2 NiH 4 and metal Mn was detected, leading to a synergistic effect that significantly enhanced the hydrogen storage capability of MgH 2. This study presents innovative concepts for designing active catalysts to enhance the kinetics of de-/hydrogenation reactions of MgH 2. [Display omitted] • Ni/MnO nanocomposites were successfully synthesized. • Ni/MnO nanocomposites obviously improved the hydrogen storage performance of MgH 2. • Synergistic catalysis of in situ-formed Mg 2 Ni, Mg 0·9 Mn 0·1 O, and Mn was proposed. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In this paper, we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary amines. The protocol is performed at mild conditions without the use of noble metals as catalysts. A wide range of structurally diverse secondary amines could be obtained in good yields (up to 94%) with good functional group tolerance. This transformation shows good to excellent selectivity, avoiding the generation of over alkylated byproducts. [ABSTRACT FROM AUTHOR]

The urgent need to develop a sustainable and environmentally friendly method for synthesizing organophosphine compounds is underscored by their extensive applications in organic synthesis, coordination chemistry, medicinal chemistry, and photoelectric materials. Metalated covalent organic frameworks (MCOFs), which seamlessly integrate the inherent photo properties of COF with the catalytic capabilities of metal ions, offer an optimal material for efficient transformation of organics sustainably. In this study, we introduce a simple COF with nickel anchorages (Bpy‐COF‐NiCl2) as a unimolecular metallaphotocatalytic system for effective C−P bond formation. This heterogeneous photocatalyst exhibits superior catalytic performance, achieving yields of up to 95 %, and demonstrates broad substrate tolerance and functional group reactivity. Notably, the metallaphotocatalytic system has demonstrated the capability to process aryl bromides to produce the desired product, a feat not previously reported. Finally, the production and reusability test at the gram scale attests to its superior practicality for designing future organic cross‐coupling reactions. [ABSTRACT FROM AUTHOR]

Mimicking the photosynthesis of green plants to combine water oxidation with CO2 reduction is of great significance for solving energy and environmental crises. In this context, a trinuclear nickel complex, [NiII3(paoH)6(PhPO3)2]·2ClO4 (1), with a novel structure has been constructed with PhPO32− (phenylphosphonate) and paoH (2-pyridine formaldehyde oxime) ligands and possesses a reflection symmetry with a mirror plane revealed by single-crystal X-ray diffraction. Bulk electrocatalysis demonstrates that complex 1 can homogeneously catalyze water oxidation and CO2 reduction simultaneously. It can catalyze water oxidation at a near-neutral condition of pH = 7.45 with a high TOF of 12.2 s−1, and the Faraday efficiency is as high as 95%. Meanwhile, it also exhibits high electrocatalytic activity for CO2 reduction towards CO with a TOF of 7.84 s−1 in DMF solution. The excellent electrocatalytic performance of the water oxidation and CO2 reduction of complex 1 could be attributed to the two unique µ3-PhPO32− bridges as the crucial factor for stabilizing the trinuclear molecule as well as the proton transformation during the catalytic process, while the oxime groups modulate the electronic structure of the metal centers via π back-bonding. Therefore, apart from the cooperation effect of the three Ni centers for catalysis, simultaneously, the two kinds of ligands in complex 1 can also synergistically coordinate the central metal, thereby significantly promoting its catalytic performance. Complex 1 represents the first nickel molecular electrocatalyst for both water oxidation and CO2 reduction. The findings in this work open an avenue for designing efficient molecular electrocatalysts with peculiar ligands. [ABSTRACT FROM AUTHOR]

[Display omitted] Efficient and stable non-precious metal catalysts (NPMCs) for the oxygen reduction reaction (ORR) are crucial for the advancement of Zn-air batteries. Herein, we report a supramolecular self-scarifying template and confinement pyrolysis strategy to obtain an efficient ORR catalyst of well-dispersed Co 3 Fe 7 /CoC x heterostructure nanoparticles encapsulated by nitrogen-doped carbon nanotubes (Co 3 Fe 7 /CoC x @ N -CNT). The as-synthesized Co 3 Fe 7 /CoC x @ N -CNT catalyst exhibited outstanding ORR activity, with a half-wave potential of 0.88 V versus a reversible hydrogen electrode, and good stability. The Zn-air battery based on the Co 3 Fe 7 /CoC x @ N -CNT cathode achieved a peak power density of 265 mW cm−2 and a durability of over 200 h, which is superior to most reported NPMCs and even the Pt/C counterpart. The physical characterization and electrochemical poisoning experiments revealed that the Co 3 Fe 7 /CoC x nanoparticles in the core along with pyridine N and Fe–N x hosted in the carbon nanotube all acted as active sites for the ORR. Further theoretical calculations showed that the charge redistribution between the Co 3 Fe 7 /CoC x nanoparticles and the Fe–N x carbon overlayers downshifted the d-band center of Fe and optimized the adsorption ability, which boosted the ORR kinetics. This work provides an effective strategy to synthesize non-precious metal ORR catalysts with multiple active sites and highlights the synergistic role of encapsulated nanoparticles and carbon support. [ABSTRACT FROM AUTHOR]

A designed Mg 88.7 Ni 6.3 Y 5 hydrogen storage alloy containing 14H type LPSO (long-period stacking ordered) and ternary eutectic structure was prepared by regulating the alloy composition and casting. The hydrogen storage performance of the alloy was improved by adding nano-flower-like TiO 2 @C catalyst. The decomposition of the LPSO structure during hydrogenation led to the formation of plenty of nanocrystals which provided abundant interphase boundaries and activation sites. The nanoscale TiO 2 @C catalyst was uniformly dispersed on the surface of alloy particles, and the "hydrogen overflow'' effect of TiO 2 @C accelerated the dissociation and diffusion of hydrogen on the surface of the alloy particles. As a result, the in-situ endogenous nanocrystals of the LPSO structure decomposition and the externally added flower-like TiO 2 @C catalyst uniformly dispersed on the surface of the nanoparticles played a synergistic catalytic role in improving the hydrogen storage performance of the Mg-based alloy. With the addition of the TiO 2 @C catalyst, the beginning hydrogen desorption temperature was reduced to 200 °C. Furthermore, the saturated hydrogen absorption capacity of the sample was 5.32 wt.%, and it reached 4.25 wt.% H 2 in 1 min at 200 °C and 30 bar. [ABSTRACT FROM AUTHOR]

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed, which exhibits good functional group compatibility, high atomic and step economy. This protocol utilizes a strategy of synergistic catalysis with a chiral N,N′-dioxide/NiII complex and an achiral Pd0 catalyst, generating a series of multi-substituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-, Z/E- and enantioselectivity under mild conditions. Further transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product analogues. Experimental studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E- and enantioselectivity. The density functional theory (DFT) calculations further demonstrated that multiple C-H···π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state. [ABSTRACT FROM AUTHOR]

A N, S co‐doped carbon with abundant vacancy defects (NSC) anchored Pt single atoms (SAs) and nanoclusters (NCs) derived from coal pitch by a self‐assembly‐pyrolysis strategy is reported and a defect‐induced electron redistribution effect based on Pt SAs‐Pt NCs/NSC catalyst is proposed for electrocatalytic hydrogen evolution reaction (HER). The optimized catalyst featuring Pt‐N3S1 SAs and Pt NCs dual active sites exhibit excellent HER activity with an overpotential of 192 mV at a current density of 400 mA cm−2, a turnover frequency of 30.1 s−1 at an overpotential of 150 mV, which the mass activity is 13716 mA mgPt−1, 7.4 times higher than that of 20% Pt/C catalyst. In situ Raman revealsa direct correlation between the defect structure of the catalyst and hydrogen adsorption during the reaction process. Density functional theory calculation shows the defect‐induced electron redistribution between Pt‐N3S1 SAs and Pt NCs. The electrons are transferred from Pt NCs to Pt SAs, which increases the number of electrons on the surface of Pt SAs and enhances the adsorption ability of H+. Meanwhile, the dissociation ability of H* on the Pt NCs is promoted, thus synergistically promoting the HER process. [ABSTRACT FROM AUTHOR]

A highly catalytic activity dielectric barrier discharge (DBD) plasma-catalyst synergistic system was constructed by DBD plasma and Ce 0.5 Bi 0.5 VO 4 /honeycomb ceramic plate (Ce 0.5 Bi 0.5 VO 4 /HCP) catalytic coating. Various characterization techniques were employed to analyze the physicochemical properties of the prepared photocatalysts. The catalytic activity of different catalytic systems was evaluated using amoxicillin (AMX) as the target contaminant. The DBD plasma-catalyst synergistic system exhibited significantly enhanced catalytic capacity compared to the single DBD plasma system. H 2 O 2 and O 3 concentrations in the solution during the reaction were monitored, and their formation process and roles were analyzed. The TOC results indicated that AMX exhibits a good mineralization rate in the synergistic system, and the 3D EEMs further revealed the changes in organic pollutant types during the mineralization process. The possible degradation pathways of AMX were inferred through mass spectra results and theoretical calculations. Additionally, the LC 50 results for fathead minnow and daphnia show a significant downward trend of the main degradation intermediates. A possible synergistic mechanism was discussed based on the characterization results, experimental data, and relevant literature. This study offers a straightforward technical approach and theoretical backing for the synergistic wastewater treatment using DBD plasma combined with photocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom‐ and step‐economy. The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes. We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α‐pentadienylation of β‐ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes. The reaction features the construction of acyclic all‐carbon quaternary centers with high enantioselectivity, and good functional group tolerance and scalability. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Direct alkylation with skipped enynes or cyclopropropylacetylenes represents an ideal process for the installation of pentadienyl group in terms of atom‐ and step‐economy. The development of catalytic asymmetric versions has been frequently pursued and most of the successes have been achieved with enolizable aldehydes. We herein describe a synergistic chiral primary amine/Pd catalysis for asymmetric α‐pentadienylation of β‐ketocarbonyls and aldehydes with skipped enynes or cyclopropropylacetylenes. The reaction features the construction of acyclic all‐carbon quaternary centers with high enantioselectivity, and good functional group tolerance and scalability. [ABSTRACT FROM AUTHOR]