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Removal of Microcystin-LR in lake water sample by hydrophilic mesoporous silica composites under high-throughput MALDI-TOF MS detection platform

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Chinese Chemical Letters 2024年第5期35卷 380-385页

作者： Wantong Zhang Zixing Xu Guofei Dai Zhijian Li Chunhui Deng Department of chemistry Institute of Metabolism&Integrate Biology(IMIB)Fudan UniversityShanghai 200433China Jiangxi Key Laboratory of organic chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Jiangxi Academy of Water Science and Engineering Nanchang 330029China

Microcystins(MCs),a family of cyclic heptapeptide cyanotoxins,exists in aquatic environment where cyanobacterial bloom happens,which will accumulate in aquatic organisms and transfer through the food chain to higher trophic levels,posing a health risk to both animals and human *** various MCs,Microcystin-LR(MC-LR)is worthiest studied for its strong toxicity,ubiquity and *** in this work,iminodiacetic acid(IDA)decorated magnetic mesoporous silica(mSiO_(2))nanocomposites(Fe_(3)O_(4)@mSiO_(2)-IDA)were facilely synthesized which possessed the merits of large surface area(188.21 m^(2)/g),accessible porosity(2.66 nm),excellent hydrophilicity and rapid responsiveness to magnetic *** the composites were successfully employed to the removal process of Microcystin-LR in real water samples followed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS)analysis,achieving the removal efficiency above 92.5%even after ten recycles of the *** provided a potential method for removing MC-LR in aqueous environment with high effectiveness,lower costs and less secondary contamination.

关键词： Microcystin-LR Mesoporous silica Magnetic composites MALDI-TOF MS analysis

Synergistic asymmetric diarylation of tethered alkenes via C–H functionalization of simple(hetero)arenes

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Science China chemistry 2024年第8期67卷 2710-2718页

作者： Jian Yao Can Zhao 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 and Shanghai Hongkong Joint Laboratory in Chemical Synthesis Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

By virtue of the atom-and step-economy, utilization of simple arenes as a supplant of pre-prepared aryl metal species or aryl halides for the synthesis of arylated chiral molecules has attracted great attention from the synthetic community. While transition-metal-catalyzed enantioselective diarylation of tethered alkenes has been employed to prepare important chiral cyclic compounds, the direct use of simple arenes as aryl precursors is still underdeveloped, probably due to the difficulties in the effective control of the reactivity, site-selectivity and/or enantioselectivity. Herein we report an asymmetric Pd/Ag dual metal catalytic system for the non-directed, site-and enantioselective domino Heck/intermolecular C–H functionalization of *** studies showed that Pd and Ag act in cooperation in the catalysis and the chiral bisphosphine ligand plays a bifunctional role, i.e., assisting the silver species in the cleavage of the aryl C–H bond, while inducing the enantioselectivity on direct complexation with palladium. This method provides an efficient approach to the corresponding chiral oxindoles with good enantiomeric excesses from a broad scope of arenes, including fluoroarenes, heteroarenes and several complex products derived from medicines or natural products.

关键词： asymmetric Pd/Ag dual metal catalytic system simple arenes C–H functionalization bifunctional role chiral oxindoles

Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

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Chinese Journal of chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou Jingyu Hu Chuanfa Ni Xiu Wang Jinbo Hu Key Laboratory of Organofluorine chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic *** organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(NIS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a ***,in this article,we report a new and unusual reaction mode between an alkene and NIS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor *** only does this unusual single electron transfer reaction between an alkene and NIS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine

Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution

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Nano-Micro Letters 2024年第9期16卷 49-94页

作者： Xuan Wang Akang Chen XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang Key Laboratory of Cluster Science Ministry of Education of ChinaBeijing Key Laboratory of Photoelectronic and Electrophonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of Chemistry Chinese Academy of SciencesBeijing 100190People’s Republic of China

In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk *** controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various *** this context,the atomic substitution method has emerged as a favorable *** involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting *** this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC *** effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are *** enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these ***,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized.

关键词： Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis

Catalytic C-H activation-initiated transdiannulation:An oxygen transfer route to ring-fluorinated tricyclic γ-lactones

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Chinese Chemical Letters 2024年第9期35卷 145-149页

作者： Qiuyun Li Yannan Zhu Yining Wang Gang Qi Wen-Juan Hao Kelu Yan Bo Jiang School of chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China School of chemistry&Materials Science Jiangsu Normal UniversityXuzhou 221116China Key Laboratory of Life-organic Analysis of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufu 273165China

Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic ***,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted *** approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration.

关键词： C-H bond activation Enaminones Transannulation Oxygen transfer Regioselectivity

Stereodivergent synthesis ofα-fluoroα-azaarylγ-butyrolactones via cooperative copper and iridium catalysis

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Fundamental Research 2024年第1期4卷 77-85页

作者： Kui Tian Xin Chang Lu Xiao Xiu-Qin Dong Chun-Jiang Wang College of chemistry and Molecular Sciences Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Suzhou institute of Wuhan University Suzhou 215123China

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically importantα-fluoroγ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric ***,a novel asymmetric[3+2]annulation ofα-fluoroα-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization,affording a variety of enantioenrichedα-fluoroγ-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 *** addition,other azaaryl acetates bearingα-methyl,α-chlorine orα-phenyl group were tolerated well in this *** 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.

关键词： Asymmetric catalysis α-Fluoroγ-butyrolactones Synergistic catalysis Cascade reaction Stereodivergent synthesis

Lysophosphatidylcholine binds α-synuclein and prevents its pathological aggregation

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National Science Review 2024年第6期11卷 119-128页

作者： Chunyu Zhao Jia Tu Chuchu Wang Wenbin Liu Jinge Gu Yandong Yin Shengnan Zhang Dan Li Jiajie Diao Zheng-Jiang Zhu Cong Liu Interdisciplinary Research Center on Biology and chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Bio-X institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders Ministry of Education Shanghai Jiao Tong University Zhangjiang institute for Advanced Study Shanghai Jiao Tong University Department of Cancer Biology University of Cincinnati College of Medicine

Accumulation of aggregated α-synuclein(α-syn) in Lewy bodies is the pathological hallmark of Parkinson's disease(PD). Genetic mutations in lipid metabolism are causative for a subset of patients with Parkinsonism. The role of α-syn's lipid interactions in its function and aggregation is recognized, yet the specific lipids involved and how lipid metabolism issues trigger α-syn aggregation and neurodegeneration remain unclear. Here, we found that α-syn shows a preference for binding to lysophospholipids(LPLs),particularly targeting lysophosphatidylcholine(LPC) without relying on electrostatic interactions. LPC is capable of maintaining α-syn in a compact conformation, significantly reducing its propensity to aggregate both in vitro and within cellular environments. Conversely, a reduction in the production of cellular LPLs is associated with an increase in α-syn accumulation. Our work underscores the critical role of LPLs in preserving the natural conformation of α-syn to inhibit improper aggregation, and establishes a potential connection between lipid metabolic dysfunction and α-syn aggregation in PD.

关键词： α-synuclein Parkinson's disease lysophosphatidylcholine, aggregation

Magnetic Bistability in the crystaline Fullerene Radical Salt

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Chinese Journal of chemistry 2024年第17期42卷 2043-2048页

作者： Huapeng Ruan Ke Li Quanchun Sun Min Liu Zhongtao Feng Xue Dong Yue Zhao Xinping Wang State Key Laboratory of Coordination chemistry School of Chemistry and Chemical EngineeringCollaborative Innovation Center of AdvancedMicrostructuresNanjing UniversityNanjingJiangsu210023China Department College of Materials and Chemical Engineering Pingxiang UniversityPingxiangJiangxi 337055China State Key Laboratory of Organometallic chemistry Shanghai Institute of Organic ChemistryChinese Academy of ScienceShanghai 200032China

Compounds with magnetic bistability is highly attractive for the construction of switches,thermal sensors,information-storage media and memory ***,we report a crystalline fullerene radical anion salt[Na(THF)_(5)]C_(60)(1),obtained by the reduction of C_(60) with Na in solution,which exhibits magnetic bistability accompanied with one magnetostructural transition,giving low temperature(LT),high temperature(HT)phases and a metastable phase.

关键词： Magnetic bistability Fullerene radical Structural transition crystal structure Chain distortion Fullerene Magnetic materials π-πstacking

Active sites and reaction mechanisms of COhydrogenation on zinc-based mixed oxide catalysts

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Science China chemistry 2024年

作者： Zhuo-Yan Yao Si-Cong Ma Zhi-Pan Liu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Key Laboratory of Computational Physical ScienceDepartment of Chemistry Fudan University State Key Laboratory of Metal organic chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai Qi Zhi Institution

The conversion of C1 molecules, COx（CO and CO2）, to valuable chemical products has garnered ever-increasing *** many routes, the hydrogenation via thermal catalysis is particularly promising as a key clean energy technology with the increasing supply of green H2. Zinc-based mixed oxide catalysts exhibit exceptional catalytic performance in the COxhydrogenation to value-added hydrocarbons, especially in combination with zeolite. This review overviews the recent achievements in understanding the active sites and reaction mechanisms of COxhydrogenation on zinc-based mixed oxide catalysts, focusing on three most-studied zinc-based mixed oxide catalysts, namely ZncrOx, ZnAlOxand ZnZrOx. The challenges and future directions are also discussed.

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