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ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling guo Shun-Xi Li Yu-Cheng liu Yu-long Li wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu wei Ma Yuying Guan Mengyuan guo Qianqian Shao Xunming Ji Jia liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

Deciphering the role of ultra-low-loaded rhodium in niFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu guo Lanyue Zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li Yong Peng wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,niFe-MIL-53 modified with ultra-low rhodium（Rh@niFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of niFe-MIL-53 and the in-situ formed Rh@niFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between niFeOOH and niFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the niFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@niFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： X ray photoelectron spectroscopy

PREPARATION AND CHARACTERIZATION OF SPHERICAL PP/PB ALLOYS WITH MgCl_2-SUPPORTED ZIEGLER-NATTA CATALYST

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Chinese Journal of Polymer Science 2012年第5期30卷 632-641页

作者：贺爱华 yang-wei Shi guo-qing liu wei Yao bao-chen Huang Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology

Polypropylene （PP）/polybutene-1 （PB） alloys within reactor were prepared by MgCl2-supported Ziegler-Natta catalyst with sequential two-stage polymerization technology. First, propylene homo-polymerizations were carried out to form isotactic polypropylene （iPP） particles containing active catalyst. Then, butene-1 was subsequently polymerized to form polybutene-1 phase inside the iPP particles. Finally, iPP/PB alloys with spherical shape and adjustable PB content were synthesized. The catalytic activity and catalytic stereospecificity of the Z-N catalyst in the two-stage polymerization process are discussed. The composition and physical properties of the PP alloys were characterized by FT-IR, 13C-NMR, SEM, DSC and XRD. It was found that the in-reactor PP alloys are mainly composed of PP and PB with a little amount of poly（butene- co-propylene） random copolymers and poly（butene-block-propylene） block copolymers. SEM measurements verified that the PB phases with size in the range of 300-400 nm dispersed in the PP matrix uniformly. The incorporation of PB upon the PP matrix affects the properties of final products greatly.

关键词： Polymer blends and alloys Polymer synthesis Polypropylene In situ polymerization.

Deliberate design of MOF-based pre-catalyst rationalizing the structural reconstruction toward efficient oxygen evolution reaction

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Science China Chemistry 2025年

作者： Yunhui Chen Meng Tian Zhongqi Zhang Guangzhao Wang Yan guo Jing Wu Dawei Qi Zhenhua Yan Xiangyu liu Xi liu State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia University Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing School of Electronic Information Engineering Yangtze Normal University Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) State Key Laboratory of Advanced Chemical Power Sources College of Chemistry Nankai University School of Chemistry and Chemical Engineering In-situ Center for Physical Sciences Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University

Metal-organic frameworks （MOFs）,that have emerged as promising electrocatalysts in oxygen evolution reaction （OER）,usually undergo structural reconstruction to form metal hydroxides as active ***,it remains a great challenge to design and synthesize ideal MOF-based pre-catalysts for properly cognizing and utilizing the reconstruction process toward efficient OER ***,the well-defined MOF-808 is post-modified by 2-hydroxyphosphonoacetic acid （HPAA） to form a micro-adsorber that enables to capture of metal ions ***3+and ni2+ions are synergistically anchored into the microadsorber,developing a Fe/ni-containing pre-catalyst that can be dynamically electrooxidized to be an active and stable dual-site electrocatalyst denoted by R-MOF-HPAA@Feni with abundant metal *** a result,R-MOF-HPAA@Feni exhibits an excellent OER performance with a low overpotential of 272 mV and Tafel slope of 35.9 m V dec-1,as well as long-term stability over 300 h at 10 m A *** and theoretical calculations suggest the resulting catalyst mainly follows a lattice oxygen mechanism （LOM） of dual-metal-site mechanism （DMSM）.Owing to the chelating role of HPAA,the post-synthesized MOF-HPAA behaves as a trap to uniformly and firmly adhere Fe3+and ni2+ions,leading to a functionalized MOF-based pre-catalyst which can be structurally evolved into atomic level-distributed OER electrocatalysts.

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Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing wei Hongjing Wu Mengyang Li Bing wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

2D Co metal-organic framework nanosheet as an oxidase-like nanozyme for sensitive biomolecule monitoring

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Rare Metals 2023年第3期42卷 797-805页

作者： Jia-wei guo Zhong-wei yang Xiu-Li liu Li-wei Zhang wei-Bo guo Jian Zhang long-Hua Ding Institute for Advanced Interdisciplinary Research School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China School of Chemistry and Chemical Engineering Linyi UniversityLinyi276005China Department of Biology and Biological Engineering Chalmers University of Technology41296 GoteborgSweden

Nanozyme-based biomolecules sensitive and quantitative detection is an attractive strategy due to their high chemical,thermal stability and reactive ***,we have synthesized a significant number of two-dimensional(2D)cobalt-metal-organic framework(Co-MOF)nanosheets with oxidase(OXD)-like activity using a facile solvothermal method in one pot for biomolecule monitoring.

关键词： attractive cobalt facile

Structure and electrochemical performances of Mg20-xYxni10（x=0-4） alloys prepared by mechanical milling

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Rare Metals 2019年第10期38卷 954-964页

作者： yang-Huan Zhang Xi-Ping Song Pei-long Zhang Yong-guo Zhu Hui-Ping Ren bao-wei Li Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Whole Win Materials Sci.&Tech.Co. Ltd.Beijing 100083Chin

Mg2ni-type Mg20-xYxni10(x=0,1,2,3 and4) electrode alloys were fabricated by vacuum induction ***,the as-cast alloys were mechanically milled on a planetary-type ball *** effects of milling time and Y content on the microstructures and electrochemical performances of the alloys were investigated in *** results show that nanocrystalline and amorphous structure can be successfully obtained through mechanical *** substitution of Y for Mg facilitates the glass forming of the Mg2ni-type alloy and significantly enhances the electrochemical characteristics of the alloy ***,the discharge capacity of Y-free alloy monotonously grows with the milling time prolonging,while that of the Y-substituted alloys has the maximum values in the same *** milling time of obtaining the greatest discharge capacity markedly decreases with Y content *** electrochemical kinetics of the alloys,including high rate discharge ability(HRD),diffusion coefficient(D),limiting current density(IL) and charge transfer rate,monotonously increase with milling time extending.

关键词： Mg2ni-type alloy Y substitution for Mg Milling duration Electrochemical performances

Simulation study of the purification system for indoor oil mist control in machining factories

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Building Simulation 2023年第8期16卷 1361-1374页

作者： Yukun Wang Yu guo Wenjia Hao wei liu Zhengwei long Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityWeijin Road 92Tianjin 300072China Division of Sustainable Buildings Department of Civil and ArchitecturalEngineeringKTH Royal Institute of TechnologyBrinellvägen 23Stockholm10044Sweden

High-concentration oil mists can cause serious health problems to workers,which are generally mitigated by ventilation and purification ***,the coupling relationship between these systems is not *** this study,the effects of purifier outlet direction,purification air volume,installation height,and purification efficiency on indoor oil mist distribution were investigated by numerical simulation using an actual machining *** mitigation of oil mist in various combinations of ventilation and purification systems was also *** results show that the outlet direction of the purifier has a great influence on the distribution of oil mist in the factory,and the maximum difference of oil mist concentration in the breathing zone under different orientations is 17%.The best purifier outlet direction is vertically *** the purifier outlet direction is upward,a larger purification air volume is beneficial for contaminant removal,and a lower purifier exhaust installation height is helpful for oil mist discharge from the bottom of the factory and reducing the concentration of oil mist in the breathing *** oil mist concentration of purifier exhaust increases from 0 to 2 mg/m^(3) and the oil mist concentration in the breathing zone increases by 67%.The combined system of purification system with the roof exhaust system and displacement ventilation system has the optimal pollution removal efficiency and the lowest concentration of oil mist in the breathing zone compared to other *** research results can provide a reference for the design,installation,and operation of ventilation and purification systems in machining factories.

关键词： oil particulate matter purification system ventilation system indoor air quality CFD