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Asymmetric Two-Component Alkenyl Catellani Reaction for the Construction of C—N Axial Chirality

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Chinese Journal of Chemistry 2024年第7期42卷 699-704页

作者： Chenggui Wu Ze-Shui Liu Yong Shang Chang Liu Shuang Deng Hong-Gang Cheng Hengjiang Cong Yinchun Jiao Qianghui Zhou Sauvage Center for Molecular Sciences Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)Hubei Key Lab on Organic and Polymeric OptoElectronic MaterialsCollege of Chemistry and Molecular SciencesThe Institute for Advanced Studiesand TaiKang Center for Life and Medical SciencesWuhan UniversityWuhanHubei 430072China Key Laboratory of Xin'an Medicine Ministry of EducationAnhui University of Chinese MedicineHefeiAnhui 230038China School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtanHunan 411201China

Herein,we report an asymmetric two-component alkenyl Catellani reaction for the construction of C—N axial chirality through a palladium/chiral norbornene cooperative catalysis and an axial-to-axial chirality transfer *** partially aromatic iodinated 2-pyridones,quinolones,coumarin and uracil substrates react with 2,6-disubstituted aryl bromides with a tethered amide group,to afford a wide variety of polycyclic C—N atropisomers(38 examples,up to 97%e.e.).The obtained C—N axial chirality originates from the preformed transient C—C axial chirality with high *** synthetic utility of this chemistry is demonstrated by facile prepa-ration of complex quinoline and pyridine based C—N atropisomers through a N-deprotection and aromatization *** addi-tion,a remote axial-to-central diastereoinduction process dictated by C—N axial chirality is observed with excellent diastereocontrol.

关键词： Alkenyl Catellani reaction Asymmetric catalysis Atropisomerism Axial-to-axial chirality transfer Heterocycles

Thermal Hall effect and the Wiedemann–Franz law in Chern insulator

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Chinese Physics B 2023年第10期32卷 579-584页

作者：王安新秦涛 School of Physics and Optoelectronics Engineering Anhui UniversityHefei 230601China

Thermal Hall effect, where a transverse temperature difference is generated by implementing a longitudinal temperature gradient and an external magnetic field in the perpendicular direction to systems, is a useful tool to reveal transport properties of quantum materials. A systematic study of the thermal Hall effect in a Chern insulator is still lacking. Here,using the Landauer–Büttiker formula, we investigated the thermal Hall transport of the Harper–Hofstadter model with flux φ= 1/2 and its generalizations. We demonstrated that the Wiedemann–Franz law, which states that the thermal Hall conductivity is linearly proportional to the quantum Hall conductivity in the low temperature limit, is still valid in this Chern insulator, and that the thermal Hall conductivity can be used to characterize the topological properties of quantum materials.

关键词： thermal Hall effect quantum Hall effect Chern insulator Landauer–Büttike formula

Transition-metal-free synthesis of 1,4-benzoxazepines via[4+3]-cycloaddition of para-quinone methides with azaoxyallyl cations

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Science China Chemistry 2021年第1期64卷 61-65页

作者： Shuang-Jing Zhou Xiao Cheng Chun-Xia Hu Guo-Yong Xu Wen-Jing Xiao Jun Xuan anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials and Key Laboratory of Functional Inorganic Materials of anhui Province College of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(anhui university) Ministry of EducationHefei 230601China Key Laboratory of Pesticide&Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China AInstitute of Physical Science and Information Technology Anhui University.Hefei 230601China

A formal[4+3]-cycloaddition reaction of ortho-hydroxyphenyl-substituted para-quinone methides(p-QMs)with in-situ generated azaoxyallyl cations is *** reaction occurs under very mild reaction conditions(transition-metal free,room temperature,cheap inorganic base)and provides a very efficient route to a series of biologically important 1,4-benzoxazepine derivatives in good to excellent yields.

关键词： 1,4-benzoxazepines para-quinone methides azaoxyallyl cations cycloaddition transition-metal-free

General synthesis of transition metal nitride arrays by ultrafast flash Joule heating within 500 ms

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Science China Chemistry 2024年第6期67卷 1976-1982页

作者： Peiqi Shen Jiahui Zhao Yanan Gao Yunxiang Lin Yuchen Han Kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China Institutes of Physical Science and Information Technology Center of Free Electron Laser&High Magnetic FieldLeibniz International Joint Research Center of Materials Sciences of Anhui ProvinceAnhui UniversityHefei230601China

Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic ***,the conventional synthetic processes for TMNs suffer from high energy consumption and low production *** this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 *** a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(*** hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.

关键词： flash Joule heating rapid synthesis transition metal nitrides hydrazine oxidation reaction electrocatalysts

Visible light and base promoted O-H insertion/cyclization of para-quinone methides with aryl diazoacetates: An approach to 2,3-dihydrobenzofuran derivatives

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Chinese Chemical Letters 2021年第8期32卷 2577-2581页

作者： Shuangjing Zhou Baogui Cai Chuxia Hu Xu Cheng Lei Li Jun Xuan anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(anhui university) Ministry of EducationHefei 230601China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China

A visible light and base promoted O-H insertion/cyclization of para-quinone methides with aryl diazoacetates is developed. This one-pot two step reaction offers a mild and efficient approach for the synthesis of biolo... 详细信息

关键词： Carbene 2 3-Dihydrobenzofuran Visible light para-Quinone methides Aryl diazoacetates

Resin-bonded NdFeB micromagnets for integration into electromagnetic vibration energy harvesters

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Journal of Zhejiang university-Science C(Computers and Electronics) 2013年第4期14卷 283-287页

作者： Pei-hong WANG Kai TAO Zhuo-qing YANG Gui-fu DING School of Physics and Material Science Anhui University Institute of Micro/Nano Science and Technology Shanghai Jiao Tong University

A micromachining technique is presented for the fabrication of resin-bonded permanent magnets in the *** paste is prepared from NdFeB powder and an epoxy resin,filled into lithographically defined photoresist molds or metal molds,and formed into resin-bonded magnets after curing at room temperature.A coercivity of 772.4 kA/m,a remanence of 0.27 T,and a maximum energy product of 22.6 kJ/m3 have been achieved in an NdFeB disk micromagnet with dimensions of Ф200 μm×70 μ*** on the developed micro-patterning of resin-bonded magnets,a fully integrated electromagnetic vibration energy harvester has been designed and *** dimensions of the energy harvester are only 4.5 mm×4.5 mm×1.0 mm,and those of the micromagnet are 1.5 mm×1.5 mm×0.2 *** microfabrication technique can be used for producing permanent magnets tens or hundreds of micrometers in size for use in various magnetic devices.

关键词： NdFeB Micromagnet Resin-bonded Electromagnetic vibration energy harvester

Controllable selective anchoring of subnanometric Ru clusters or single-atoms/clusters on tungsten nitride for the hydrogen oxidation

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Science China Chemistry 2024年第11期67卷 3749-3756页

作者： Qijiao Sun Chuanqiang Wu Yiqiang Sun Yuan Shen Lei Zhao Xiaodong Yang Li Yang Yunxiang Lin Keke Mao Kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Information Materials and Intelligent Sensing Laboratory of anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China School of Chemistry and Chemical Engineering University of JinanJinan 250022China School of Energy and Environment Anhui University of TechnologyMa’anshan 243032China

The impregnation method in the preparation of metal cluster catalysts typically inadvertently introduces single atoms(SAs) into the substrate. However, the question of whether the introduction of SAs will further improve the catalytic activity of cluster systems for specific reactions such as the hydrogen oxidation reaction(HOR) remains unraveled. Herein, we demonstrate Ru clusters anchored on WN nanowires(RuC/WN) show a higher alkaline HOR catalytic activity in comparison with Ru SAs and nanoclusters(NCs)-coupled catalyst anchored on WN nanowires system(RuC,S/WN). Notably, the RuC/WN exhibits superb intrinsic catalytic activity with a mass-normalized exchange current density of 890 m A mg^(-1)PGM, which is among the top level of well developed Ru-based HOR catalysts. Both theoretical simulation and experimental investigation suggest that RuC/WN owns an optimized H^(*)and OH^(*) reaction intermediates for the alkaline HOR, therefore resulting in the excellent intrinsic HOR catalytic performance.

关键词： hydrogen oxidation reaction Ru cluster catalyst Ru single atoms and nanoclusters coupled catalyst tungsten nitride substrate

Visible Light-Promoted Sulfoxonium Ylides Synthesis from Aryl Diazoacetates and Sulfoxides

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Chinese Journal of Chemistry 2021年第6期39卷 1646-1650页

作者： Juan Lu Lei Li Xiang-Kui He Guo-Yong Xu Jun Xuan anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefeiAnhui 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(anhui university) Ministry of EducationHefeiAnhui 230601 China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province School of ScienceWestlake University18 Shilongshan RoadHangzhouZhejiang 310024China Institute of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China

A visible light-promoted reaction of donor/acceptor diazoalkanes with sulfoxides towards the synthesis of synthetically useful sulfoxonium ylides was *** reaction occurred under sole visible light irradiation without the need of any transition-metals or additives,affording the corresponding sulfoxonium ylides in moderate to good *** success of late-stage modification of natural isolates or drug candidates,scale-up reaction and transformation of sulfoxonium ylides to other useful molecules further rendered the approach valuable.

关键词： Sulfoxonium ylides Synthetic methods Carbene Visible Light Diazo compounds

The Possibility of Detecting our Solar System through Astrometry

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Research in Astronomy and Astrophysics 2023年第11期23卷 198-204页

作者： Dong-Hong Wu Department of Physics Anhui Normal UniversityWuhu 241000China

Searching for exoplanets with different methods has always been the focus of astronomers over the past few *** multiple planet detection techniques,astrometry stands out for its capability to accurately determine the orbital parameters of *** this study,we examine the likelihood of extraterrestrial intelligent civilizations detecting planets in our solar system using the astrometry *** conducting injection-recovery simulations,we investigate the detectability of the four giant planets in our solar system under different observing baselines and observational *** findings indicate that extraterrestrial intelligence could detect and characterize all four giant planets,provided they are observed for a minimum of 90 yr with signal-noise ratios exceeding *** individual planets such as Jupiter,Saturn,and Neptune,a baseline that surpasses half of their orbital periods is necessary for ***,Uranus requires longer observing baselines since its orbital period is roughly half of that of *** the astrometry precision is equal to or better than 10μas,all 8707 stars located within30 pc of our solar system possess the potential to detect the four giant planets within 100 ***,our prediction suggests that over 300 stars positioned within 10 pc from our solar system could detect our Earth if they achieve an astrometry precision of 0.3μas.

关键词： astrometry planets and satellites:detection Planetary Systems