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Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin Dong-Sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of chemical Reaction {1. College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 201. to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1.3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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Iron-nickel alloy particles with N-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of Nbenzylaniline molecules

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Nano Research 2024年第4期17卷 2308-2319页

作者： Gang Wang Longchao Sun Wanyi Liu Haijuan Zhan Shuxian Bi college of {1. and chemical engineering Ningxia UniversityYinchuan 750021China

A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was *** controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted ***_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple ***,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)*** N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy *** carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.

关键词： iron-nickel alloy catalyst N-alkylation reaction magnetic separation reaction path dehydrogenation reaction

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Micro/nanoelectrode-based electrochemical methodology for single cell and organelle analysis

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Nano Research 2024年第1期17卷 196-206页

作者： Chuchu Xu De Yang Yuchan Wang Ruolin Liu Fan Wang Zhongqun Tian Keke Hu Department of chemistry College of Chemistry&Chemical EngineeringXiamen UniversityXiamen 361005China

Cells are the basic unit of *** analysis of single cells/organelles is essential for uncovering the molecular mechanisms of physiological and pathological processes that are difficult to elucidate on a larger *** paper provides an overview of the commonly used fabrication methods for micro/nanoelectrodes applied in the investigations of single cells/organelles as well as the corresponding electrochemical measurements over the last four years including extracellular measurement,combination of extra and intracellular measurement,intracellular reactive oxygen species and reactive nitrogen species(ROS/RNS)measurement,and isolated organelles measurement.

关键词： single cell/organelle micro/nanoelectrode electrochemical measurement chemical transmitters

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Fe3O4/Fe/FeS Tri-Heterojunction Node Spawning N-Carbon Nanotube Scaffold Structure for High-Performance Sodium-Ion Battery

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Energy & Environmental Materials 2024年第4期7卷 143-152页

作者： Yuan Liu Qing Lin Xiaocui Chen Xufeng Meng Baoxiu Hou Haiyan Liu Shuaihua Zhang Ningzhao Shang Zheng Wang Chaoyue Zhang Jianjun Song Xiaoxian Zhao Department of chemistry College of Science Hebei Agricultural University college of {1. and chemical engineering Qingdao University college of Physics Qingdao University

The Fe-based anode of sodium-ion batteries attracts much attention due to the abundant source,low-cost,and high specific ***,the low electron and ion transfer rate,poor structural stability,and shuttle effect of NaS2intermediate restrain its further ***,the Fe3O4/Fe/FeS tri-heterojunction node spawned N-carbon nanotube scaffold structure（FHNCS） was designed using the modified MIL-88B（Fe） as a template followed by catalytic growth and sulfidation process.

关键词： anode core-shell heterojunction hollow structure sodium ion batteries

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Two-dimensional C_(2)N-based single-atom catalyst with complex microenvironment for enhanced electrochemical nitrogen reduction:A descriptor-based design

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Journal of Energy chemistry 2024年第10期97卷 110-119,I0003页

作者： Enduo Dai Wei An Ruixian Guo Xugen Shi Yunyi Li Yibo Wang Mingming Liu college of {1. and chemical engineering.Shanghai University of engineering Science Shanghai 201620China

The catalytic descriptor with operational feasibility is highly desired towards rational design of high-performance catalyst especially the electrode/electrolyte solution interface working under mild ***,we demonstrate that the descriptorΩparameterized by readily accessible intrinsic properties of metal center and coordination is highly operational and efficient in rational design of single-atom catalyst(SAC)for driving electrochemical nitrogen reduction(NRR).Using twodimensional metal(M)-B_(x)P_(y)S_(z)N_m@C_(2)N as prototype SAC models,we reveal that^(*)N_(2)+(H~++e~-)→^(*)N_(2)H acts predominantly as the potential-limiting step(PLS)of NRR on M-B_(2)P_(2)S_(2)@C_(2)N and M-B_(1.P_(1.S_(1.N_(3)@C_(2)N regardless of the distinction in coordination *** the 28 screened M active sites,withΩvalues close to the optimal 4,M-B_(2)P_(2)S_(2)@C_(2)N(M=V(Ω=3.53),Mo(Ω=5.1.),and W(Ω=3.92))and M-B_(1.P_(1.S_(1.N_(3)@C_(2)N(M=V(Ω=3.00),Mo(Ω=4.34),and W(Ω=3.32))yield the lowered limiting potential(U_(L))as-0.45,-0.54.-0.36,-0.58,-0.25,and-0.24 V,respectively,thus making them the promising NRR *** importantly,these SACs are located around the top of volcano-shape plot of U_(L) versusΩ,re-validatingΩas an effective descriptor for accurately predicting the high-activity NRR SACs even with complex *** study unravels the relationship between active-site structure and NRR performance via the descriptorΩ,which can be applied to other important sustainable electrocatalytic reactions involving activation of small molecules viaσ-donation andπ^(*)-backdonation mechanism.

关键词： Electrocatalysis N_(2) reduction Single-atom catalyst Descriptor DFT

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Tough lanthanide luminescent hydrogel for nitroaromatics detection

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Journal of Rare Earths 2024年第2期42卷 293-302,I0003页

作者： Shu Xie Fei Li Fengyi Liu Quanqing Xu Xufeng Zhang college of {1. and chemical engineering Yunnan Normal UniversityKunming650092China

Luminescent hydrogels have received considerable attention in the application of *** matics are harmful to human health and can be *** skin allergies and central nervous system injuries may also be attributed to the over exposure to ***,nitroaromatics sensor with fast detection and low detection limit is highly ***,novel tough hydrogels were prepared by introducing hydrogen bonds and covalent bonds into the interpenetrating networks of modified chitosan and poly(vinyl alcohol)(PVA) via frozen-thawing induced chemical *** synthesized hydrogels exhibit high mechanical strength(0.23 MPa tensile strength at 1.0% tensile strain,1.0 MPa compressive strength at 80% compressive strain).Strong green emission was realized by energy transfer from the modified chitosan to Tb^(3+)via the so-called "antenna effect." The prepared luminescent hydrogels show an excellent detection effect on nitroaromatic compounds and its detection limit can reach *** hydrogels also exhibit good reversibility and a fast "off-on" fluorescence switching *** work may open up a new way for the development of stable,rapid,and reusable sensors for the detection of harmful nitroaromatics.

关键词： Hydrogels Lanthanide Luminescence Nitroaromatics Sensors Rare earths

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Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-Yang Liu Jing-Wei Liu Gang Li Jing-Xiang Zhao college of {1. and chemical engineering Harbin Normal UniversityHarbin 150025China

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and *** this work,by means of the density functional theory(DFT) calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM_(1.4)@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions(OER),oxygen reduction reactions(ORR) and hydrogen evolution reactions(HER).The computed results reveal that the Pd_(2),Pd_(4) and Pt_(1. anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.1. and 0.37/0.43/0.01.V,respectively,while Pd_(1. and Pt_(2)@graphdiyne can exhibit excellent catalytic performance for water splitting(OER/HER) with the overpotentials of 0.55/0.1. and 0.43/0.03 *** addition,Ni_(1. and Pd_(3) anchored GDY can perform as bifunctional catalysts for metal-air cells(OER/ORR) and fuels cells(ORR/HER) with the overpotentials of 0.34/0.32 and 0.42/0.04 V,***,by precisely controlling the numbers of atoms in clusters,the TM_(1.4) anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

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Programmed DNA walkers for biosensors

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Chinese chemical Letters 2024年第9期35卷 119-129页

作者： Chang Liu Tao Wu Lijiao Deng Xuzi Li Xin Fu Shuzhen Liao Wenjie Ma Guoqiang Zou Hai Yang School of chemistry and {1. engineering Hunan Institute of EngineeringXiangtan 411104China college of {1. and chemical engineering Central South UniversityChangsha 410083China

Nowadays,due to excellent biological and polymeric characteristics,DNA has been widely noted as an emerging building block to construct diverse materials for biosensing,in vivo imaging,drug delivery,and disease ***,relying on programmability,predictability,and stability of DNA,DNA walkers have opened new and exciting opportunities in modern life sciences for target detection and biological analysis,which are constructed by self-assembly of DNA or combining DNA with other nanomaterials(e.g.,quantum dots,gold nanoparticles,magnetic nanoparticles,polymers).Compared with conventional nanomaterials(lanthanide-doped upconversion nanoparticles,magnetic nanomaterials,carbon dots,silicon dots,and so on),DNA walkers showed convenient modification,lower biotoxicity,excellent biocompatibility and high biostability,improving the biological ***,with high-speed operating efficiency and sustainable operation,DNA walkers powered by strand displacement reaction or protein enzyme/DNAzyme reaction,have highly sensitive detection and signal amplification abilities,which are applied in biosensing,material assembly and synthesis,and early cancer ***,DNA walkers could be regarded as signal amplifiers,which enhanced the signal transduction and amplified biosensor sensing ***,we systematically and comprehensively summarized the operating principles of various DNA walkers,categorized rational design of the DNA walker,and outlined the application of DNA walker in ***,the challenges and future trends of DNA walkers were discussed.

关键词： DNA walker Biosensors Signal amplification strategies Operating principles Design strategies

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Cooperation between single atom catalyst and support to promote nitrogen electroreduction to ammonia:A theoretical insight

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Journal of Energy chemistry 2024年第9期96卷 336-344页

作者： Wanying Guo Siyao Wang Hongxia Wang Qinghai Cai Jingxiang Zhao college of {1. and chemical engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

The co-catalysis between single atom catalyst(SAC)and its support has recently emerged as a promising strategy to synergistically boost the catalytic activity of some complex electrochemical reactions,encompassing multiple intermediates and ***,we utilized defective BC_(3)monolayer-supported SACs as a prototype to investigate the cooperative effects of SACs and their support on the catalytic performance of the nitrogen reduction reaction(NRR)for ammonia(NH_(3))*** results showed that these SACs can be firmly stabilized on these defective BC_(3)supports with high stability against ***,co-activation of the inert N_(2)reactant was observed in certain embedded SACs and their neighboring B atoms on certain BC3 sheets due to the noticeable charge transfer and significant N–N bond *** high-throughput screening revealed that the Mo/DV_(CC)and W/DV_(CC)exhibit superior NRR catalytic performance,characterized by a low limiting potential of−0.33 and−0.43 V,respectively,which can be further increased under acid conditions based on the constant potential ***,varying NRR catalytic activities can be attributed to the differences in the valence state of active ***,further microkinetic modeling analysis displayed that the turnover frequency of N_(2)–to–NH_(3)conversion on Mo/DV_(CC)is as large as 1.20×1.^(−3)s^(−1.site^(−1. at 700 K and 1.0 bar,thus guaranteeing its ultra-fast reaction *** results not only suggest promising advanced electrocatalysts for NRR but also offer an effective avenue to regulate the electrocatalytic performance via the co-catalytic metal–support interactions.

关键词： Co-catalysis Single atom catalyst Nitrogen reduction DFT computations

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Enhancing the electrocatalytic performance of nitrate reduction to ammonia by in-situ nitrogen leaching

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Chinese chemical Letters 2024年第2期35卷 564-569页

作者： Mimi Fu Yini Mao Hua Wang Wei Luo Yimin Jiang Wei Shen Ming Li Rongxing He college of {1. and chemical engineering Southwest UniversityChongqing 400715China

Electrochemical nitrate reduction reaction (NITRR) is regarded as a “two birds-one stone” method for the treatment of nitrate contaminant in polluted water and the synthesis of valuable ammonia, which is retarded by the lack of highly reactive and selective electrocatalysts .Herein, for the first time, nickel foam supported Co_(4) N was designed as a high-performance NITRR catalyst by an in-situ nonmetal leaching-induced *** the optimal potential, the Co_(4) N/NF catalyst achieves ultra-high Faraday efficiency and NH_(3) selectivity of 95.4% and 99.4%, *** situ X-ray absorption spectroscopy (XAS), together with other experiments powerfully reveal that the nitrogen vacancies produced by nitrogen leaching are stable and play a key role in boosting nitrate reduction to *** calculations confirm that Co_(4) N with abundant nitrogen vacancies can optimize the adsorption energies of NO_(3)^(-) and intermediates, lower the free energy (Δ G ) of the potential-determining step (*NH_(3) to NH_(3) ) and inhibit the formation of N-containing *** addition, we also conclude that the nitrogen vacancies can stabilize the adsorbed hydrogen, making H_(2) quite difficult to produce, and lowering ΔG from *NO to *NOH, which facilitates the selective reduction of *** study reveals significant insights about the in-situ nonmetal leaching to enhance the NITRR activity.

关键词： Co4N Nitrate reduction In-situ nonmetal leaching Nitrogen vacancy Mechanism

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