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Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl c–H bond: quick access to multi-substituted aryl olefins

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Science china chemistry 2024年第3期67卷 882-889页

作者： Jian Yao Lili shao Xiaohong Huo Xiaoming Wang Shanghai Key Laboratory for Molecular Engineering of chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China School of chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-catalyzed olefination of aryl c-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative c-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed c-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl c-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion.

关键词： direct c–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation c–H functionalization

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Bilayer compounded Polytetrafluoroethylene Membrane for Enhanced Oil-Water Emulsion Separation

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chinese Journal of Polymer Science 2024年第6期42卷 838-850页

作者： Yu-liang Yang Tai-Ran Zhang Yan-Ting Han shao-Yun Guo Qin-Gong Rong Jia-Bin Shen State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyChengdu610065China West china Hospital/West china School of Nursing Sichuan UniversityChengdu610041China Shandong Senrong New Materials co. Ltd.Zibo256401China

In order to achieve efficient and durable oil-water emulsion separation,the membranes possessing high separation efficiency and mechanical strength attract extensive attention and are in great demand.In present study,a kind of polytetrafluoroethylene(PTFE)-based bilayer membrane was fabricated by electrospinning fibrous PTFE(fPTFE)on an expanded PTFE(ePTFE)substrate.The morphological observation revealed that the fibrous structure of the fPTFE layer could be tailored by controlling the formulation of spinning solution.The addition of appropriate polyoxyethylene(PEO)would make the fibers in the fPTFE layer finer and more uniform.As a result,the compounded membrane exhibited a small pore size of approximately 1.25µm and a substantial porosity nearing 80%.This led to super-hydrophobicity,characterized by a high water contact angle(WcA)of 149.8°,and facilitated rapid oil permeation.The water-in-oil emulsion separation experiment further confirmed that the compounded membrane not only had a high separation efficiency closing 100%,but such an outstanding separation capacity could be largely retained,either through multiple cycles of use or through strong acid(pH=1),strong alkali(pH=12),or high-temperature(100°c)treatment.Additionally,the mechanical behavior of the bilayer membrane was basically contributed by that of each layer in terms of their volume ratio.More significantly,the poor creep resistance of fPTFE layer was suppressed by compounding with ePTFE substrate.Hence,this study has laid the groundwork for a novel approach to create PTFE-based compounded membranes with exceptional overall characteristics,showing promise for applications in the realm of emulsion separation.

关键词： ePTFE Electrospinning membrane Bilayer compounding Emulsion separation

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Therapeutic genome editing of an aberrant splice site inβ-thalassemia by cRISPR/cas9 with multiple sgRNAs

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Genes & Diseases 2024年第1期11卷 15-18页

作者： Fei Yang Shuqian Xu chao Huang Zhiqiang shao Yuefen Hu Yang Yang Yongrong Lai Qing Ke Dan liang Yuxuan Wu Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Department of Obstetrics and Gynecology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China NHc Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) HefeiAnhui 230032China Department of Hematology Qilu HospitalCheeloo College of MedicineShandong UniversityJinanShandong 250012China BRLMedicine Inc. Shanghai 201108China Department of Hematology The First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 530000China Department of Neurology The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310003China

Genetic mutations cause aberrant splicing,one of the important molecular mechanisms in human diseases.Ivs2-654,a mutation causing aberrant splicing ofβ-globin premRNA and contributing toβ-globin deficiency,is one of the most common diseases in Southeast Asia and china."In our previous work,we found a TTTV protospacer adjacent motif(PAM)by the cas12a system and the editing efficiency of Ivs2-654 c>T achieving 76.7%.

关键词： cRISPR/cas9 china thalassemia

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An Outbreak of Serogroup Y Meningococcal Meningitis in a Private Secondary Vocational School-Guangzhou city,Guangdong Province,china,2023

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china cDc weekly 2024年第12期6卷 242-246,I0005页

作者： Xiang Zeng Qing He Yilan Li Yong Zhou Xiaoping shao Pei Hu Jian liang Yudan Song chao Ma Lijie Zhang Limei Sun Lei Luo chinese Field Epidemiology Training Program Chinese Center for Disease Control and PreventionBeijingChina Zhuhai center for Disease control and Prevention Zhuhai CityGuangdong ProvinceChina Guangdong center for Disease control and Prevention Guangzhou CityGuangdong ProvinceChina Guangzhou center for Disease control and Prevention Guangzhou CityGuangdong ProvinceChina Institute of Public Health Guangzhou Medical University&Guangzhou Center for Disease Control and PreventionGuangzhou CityGuangdong ProvinceChina Department of the National Immunization Programme Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?The inclusion of meningococcal vaccines in the National Immunization Program(NIP)over several years has significantly reduced the incidence of meningococcal meningitis in china to historic lows.Worldwide,there has been a diversification of meningococcal serogroups,leading to a shift in dominant serogroups in china from serogroup A to serogroups c and B,accompanied by a rise in reports of serogroups Y and W.What is added by this report?An outbreak of serogroup Y Neisseria meningitidis(Nm)in a secondary vocational school involved a single confirmed severe case and 24 individuals with laboratory-confirmed Nm carriage.Epidemiological investigation revealed that the outbreak was localized to the classroom of the confirmed case.Prolonged close contact within a confined space was identified as a significant risk factor for Nm transmission.The genotype sequence identified was type 1655(ST-1655),which is categorized under clonal complex 23(cc-23)and bears resemblance to 8 previously confirmed cases of serogroup Y meningococcal meningitis within Guangdong Province.This suggests that serogroup Y infections continue to sporadically emerge and have become prevalent strains.What are the implications for public health practice?This outbreak underscores the critical need to enhance surveillance of meningococcal serogroups and population carrier,and advocate for vaccination with MenY-containing vaccines.

关键词： break Secondary Guangdong

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Intensive management enhances mycorrhizal respiration but decreases free-living microbial respiration by affecting microbial abundance and community structure in Moso bamboo forest soils

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Pedosphere 2024年第2期34卷 508-519页

作者： Wenhao JIN Jiangfei GE Shuai shao Liyuan PENG Jiajia XING chenfei liang Junhui cHEN Qiufang XU Hua QIN State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China School of Environmental and Resource Sciences Zhejiang A&F UniversityHangzhou 311300China

Intensive management is known to markedly alter soil carbon(c)storage and turnover in Moso bamboo forests compared with extensive management.However,the effects of intensive management on soil respiration(RS)components remain unclear.This study aimed to evaluate the changes in different RScomponents(root,mycorrhizal,and free-living microorganism respiration)in Moso bamboo forests under extensive and intensive management practices.A1-year in-situ microcosm experiment was conducted to quantify the RScomponents in Moso bamboo forests under the two management practices using mesh screens of varying sizes.The results showed that the total RSand its components exhibited similar seasonal variability between the two management practices.compared with extensive management,intensive management significantly increased cumulative respiration from mycorrhizal fungi by 36.73%,while decreased cumulative respiration from free-living soil microorganisms by 8.97%.Moreover,the abundance of arbuscular mycorrhizal fungi(AMF)increased by 43.38%,but bacterial and fungal abundances decreased by 21.65%and 33.30%,respectively,under intensive management.Both management practices significantly changed the bacterial community composition,which could be mainly explained by soil pH and available potassium.Mycorrhizal fungi and intensive management affected the interrelationships between bacterial members.Structural equation modeling indicated that intensive management changed the cumulative RSby elevating AMF abundance and lowering bacterial abundance.We concluded that intensive management reduced the microbial respiration-derived c loss,but increased mycorrhizal respiration-derived c loss.

关键词： arbuscular mycorrhizal fungi extensive management microbial co-occurrence network root respiration soil organic c soil respiration structural equation model

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Growth of Ag/g-c_(3)N_(4) nanocomposites on nickel foam to enhance photocatalytic degradation of formaldehyde under visible light

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Journal of Environmental Sciences 2024年第3期137卷 432-442页

作者： Ze Wang Zhi Huang Jiang Yu Xiao shao Weidong Peng Jie Yu Yinying Jiang Department of Environmental Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Institute of New Energy and Low carbon Technology Sichuan UniversityChengdu 610065China School of Agriculture and Environment University of Western AustraliaPerth 6907Western AustraliaAustralia Yibin Institute of Industrial Technology Sichuan UniversityYibin 644000China

Formaldehyde is a pollutant that significantly affects the indoor air quality.However,conventional remediation approaches can be challenging to deal with low-concentration formaldehyde in an indoor environment.In this study,Photocatalysts of Ag/graphitic carbon nitride(g-c_(3)N_(4))/Ni with 3D reticulated coral structure were prepared by thermal polymerization and liquid phase photo-deposition,using nickel foam(NF)as the carrier.Experiments demonstrated that when the Ag concentration was 3%,and the relative humidity was 60%,the Ni/Ag/g-c_(3)N_(4)showed the maximum degradation rate of formaldehyde at 90.19%under visible light irradiation,and the formaldehyde concentration after degradation was lower than the Hygienic standard stated by the chinese Government.The porous structure of Ni/Ag/g-c_(3)N_(4)and the formation of Schottky junctions promoted the Adsorption efficiency and degradation of formaldehyde,while the nickel foam carrier effectively promoted the desorption of degradation products.Meanwhile,the degradation rate was only reduced by3.4%after 16 recycles,the three-dimensional porous structure extended the lifetime of the photocatalyst.This study provides a new strategy for the degradation of indoor formaldehyde at low concentrations.

关键词： Graphitic carbon nitride(g-c_(3)N_(4)) Nickel foam(NF) Ag Formaldehyde Photocatalysis

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Enhancement of low-temperature toughness of Fe-Mn-c-Al alloy by rare earth ce-modified inclusions

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Journal of Iron and Steel Research(International) 2024年第1期31卷 157-173页

作者： Guang-kai Yang chang-ling Zhuang Yi-zhuang Li chen Hu shao-bo Li college of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-c-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and cost-effectiveness.However,their limited low-temperature toughness restricts their large-scale applications in specific scenarios.The influence of trace amounts of rare earth cerium(ce)on the low-temperature toughness of Fe-18Mn-0.6c-1.8Al alloys was investigated.The addition of ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth inclusions.This leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic performance.The presence of ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption energy.Specifi-cally,the addition of rare earth ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure mode.The impact toughness of the Fe-Mn-c-Al alloy is significantly improved by the addition of 0.0048 wt.%ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-c-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

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Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(c_(6)F_(5))_(3)/chiral phosphoric acid

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chinese chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu Zhi-Yuan Ren chen Yang Xiangyi shao Li chen Xin Li State Key Laboratory of Elemento-Organic chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive challenge.Herein,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(c_(6)F_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction conditions.Moreover,the synthetic utility was confirmed by the scaled-up reaction and transformations of the products.The mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DFT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(c_(6)F_(5))_(3)/chiral phosphoric acid Theoretical calculations

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Graphdiyne(c_nH2n-2) as an "electron transfer bridge" boosting photocatalytic hydrogen evolution over Zn0.5co0.5S/MoS2 S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li Jing-Zhi Wang Zhi-liang Jin School of chemistry and chemical Engineering North Minzu University School of chemistry and chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion Technology Key Laboratory for Chemical Engineering and Technology State Ethnic Affairs Commission North Minzu University

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the catalyst.In this paper,a carbon isotope superconducting material graphdiyne （GDY） is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn0.5co0.5S/Mo S2inorganic system.In terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated charges.Morphologically,the large twodimensional layer provides more loading and anchoring points for Zn0.5co0.5S/Mo S2,which increases the number of active sites.The ternary composite catalyst 20%GDY/Zn0.5co0.5S/Mo2S （20-GcSM） generates 69.94μmol of hydrogen （5 h） in triethanolamine solution.It is 2.97 and1.80 times higher than Zn0.5co0.5S and Zn0.5co0.5S/Mo S2,respectively.After the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h （under dark conditions）.In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron spectroscopy.This work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

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Texture and Geochemistry of Multi-stage Hydrothermal Scheelite in the Mamupu cu-Au-Mo(-W)Deposit,Eastern Tibet:Implications for Tungsten Mineralization in the Yulong Belt

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 701-716页

作者： ZHANG Xiaoxu TANG Juxing LIN Bin WANG Qin HE liang YAN Gang shao Rui WU Qiang DU Qiu ZHAXI Pingcuo chengdu center China Geological Survey(Geosciences Innovation Center of Southwest China)Chengdu 610081China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China Earth Sciences college Chengdu University of TechnologyChengdu 610059China No.6 Geological Party Tibetan Bureau of Geology and Mineral Exploration and DevelopmentLhasa 851400China Tibet Shengyuan Mining Group co. Ltd.Lhasa 851400China

Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPcB),Tibet.This study reports the results of cathodoluminescence,trace element and Sr isotope analyses of Mamupu scheelite samples,undertaken in order to better constrain the mechanism of W mineralization and the sources of the ore-forming fluids.Three different types of scheelite are identified in the Mamupu deposit:scheelite A(Sch A)mainly occurs in breccias during the prograde stage,scheelite B(Sch B)forms in the chlorite-epidote alteration zone in the retrograde stage,while scheelite c(Sch c)occurs in distal quartz sulfide veins.The extremely high Mo content and negative Eu anomaly in Sch A represent high oxygen fugacity in the prograde stage.compared with ore-related porphyries,Sch A has a similar REE pattern,but with higher ΣREE,more depleted HREE and slightly lower(^(87)Sr/^(86)Sr)i ratios.These features suggest that Sch A is genetically related to ore-related porphyries,but extensive interaction with carbonate surrounding rocks affects the final REE and Sr isotopic composition.Sch B shows dark(Sch B-I)and light(Sch B-II)domains under cL imaging.From Sch B-I to Sch B-II,LREEs are gradually depleted,with MREEs being gradually enriched.Sch c has the highest LREE/HREE ratio,which indicates that it inherited the geochemical characteristics of fluids after the precipitation of HREE-rich minerals,such as diopside and garnet,in the early prograde stage.The Mo content in Sch B and Sch c gradually decreased,indicating that the oxygen fugacity of the fluids changed from oxidative in the early stages to reductive in the later,the turbulent Eu anomaly in Sch B and Sch c indicating that the Eu anomaly in the Mamupu scheelite is not solely controlled by oxygen fugacity.The extensive interaction of magmatic-hydrothermal fluids and carbonate provides the necessary ca^(2+)for the precipitation of scheelite in the Mamupu deposit.

关键词： scheelite geochemistry Mamupu cu deposit Yulong porphyry copper belt eastern Tibet

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