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Copper-catalyzed asymmetric dearomatizing amination of 2-naphthols:Csp^(2)–n coupling via 1,3-reductive elimination

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Science China Chemistry 2024年第8期67卷 2694-2700页

作者： Aying Yihuo Maoping Pu Zheng tan Jibang Liao Jiuqi tan Qi-Lin Zhou Xiaohua Liu Xiaoming Feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Frontiers Science Centerfor New Organic MatterNankai UniversityTianjin300071China

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by n,n′-dioxide-copper(I)complex as a chiral catalyst was presented.A variety of optically activeβ-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction *** studies indicated that this Csp^(2)–n dearomatizing coupling proceeds via 1,3-reductive elimination of phenolate-Cu~Ⅲ-amino intermediate in five-membered ring transition *** origin of enantioselectivity has also been elucidated based on density functional theory calculations.

关键词： asymmetric catalysis amination dearomatization copper catalysis coupling reaction

The Ti-tan plasmid toolbox for TurboID-based proximity labeling assays in nicotiana benthamiana

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Journal of Integrative Plant Biology 2024年第2期66卷 166-168页

作者： Huang tan Yu Zhou Erik Dinius Rosa Lozano-Durán Department of Plant Biochemistry Center for Plant MolecularBiology(ZMBP)Eberhard Karls UniversityTubingenD‐72076Germany

Protein-protein interactions and the formation of protein complexes play a central role in the regulation of virtually all aspects of *** identification and characterization of interactions between proteins is the bas... 详细信息

关键词： proximity complexes enable

n,O-Bidentated difluoroboron complexes based on pyridine-ester enolates:Facile synthesis,post-complexation modification,optical properties,and applications

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Chinese Chemical Letters 2024年第9期35卷 169-174页

作者： Chaochao Jin Kai Li Jiongpei Zhang Zhihua Wang Jiajing tan College of Chemistry Beijing University of Chemical Technology(BUCT)Beijing 100029China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055China

An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and *** rapid structure-activity relationship(SAR)studies indicated that unsymmetrical n,O-chelated BF2complexes were highly fluorescent in solid state,and exhibited large Stokes shifts,excellent photostability,along with insensitivity to p ***α-aryl group could not only modulate the electronic effect but also inhibit the intermolecularπ-πstacking to promote the aggregation-induced emission(AIE)*** calculations and experiments identified that the intramolecular charge transfer properties of these n,O-chelates could be switched by the modification of substituents,resulting tunable fluorescence ***,post-complexation modification was accomplished,including Suzuki-Miyaura cross-coupling,Buchwald-Hartwig amination,oxidative cleavage,along with a unique triple substitution reaction involving propargyl Grignard *** exemplificative application of dimethylamine substituted boron complex as a reversible acidic vapor sensor was also demonstrated.

关键词： n,O-Bidentate BF2 complexes Aggregation-induced emission Large Stokes shift Post-complexation modification Reversible acidic vapor sensor

Delving into the dissimilarities in electrochemical performance and underlying mechanisms for sodium and potassium ion storage in n-doped carbon-encapsulated metallic Cu_(2)Se nanocubes

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Journal of Energy Chemistry 2024年第8期95卷 336-347,I0008页

作者： Xinyu Wang Yanan Xu Xiaofeng Liu Lei tan Huaiqiang Gu Xin Du Dan Li College of Chemistry Zhengzhou UniversityZhengzhou 450001HenanChina Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina Institute of Theoretical Physics Lanzhou UniversityLanzhou 730000GansuChina School of nuclear Science and Technology Lanzhou UniversityLanzhou 730000GansuChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046XinjiangChina

The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical ***,metallic Cu_(2)Se encapsulated with n-doped carbon(Cu_(2)Se@nC)was prepared using Cu_(2)O nanocubes as templates through a combination of dopamine polymerization and hightemperature *** unique nanocubic structure and uniform n-doped carbon coating could shorten the ion transport distance,accelerate electron/charge diffusion,and suppress volume variation,ultimately ensuring Cu_(2)Se@nC with excellent electrochemical performance in sodium ion batteries(SIBs)and potassium ion batteries(PIBs).The composite exhibited excellent rate performance(187.7 mA h g^(-1)at 50 A g^(-1)in SIBs and 179.4 mA h g^(-1)at 5 A g^(-1)in PIBs)and cyclic stability(246,8 mA h g^(-1)at 10 A g^(-1)in SIBs over 2500 cycles).The reaction mechanism of intercalation combined with conversion in both SIBs and PIBs was disclosed by in situ X-ray diffraction(XRD)and ex situ transmission electron microscope(TEM).In particular,the final products in PIBs of K_(2)Se and K_(2)Se_(3)species were determined after discharging,which is different from that in SIBs with the final species of na_(2)*** density functional theory calculation showed that carbon induces strong coupling and charge interactions with Cu_(2)Se,leading to the introduction of built-in electric field on heterojunction to improve electron ***,the theoretical calculations discovered that the underlying cause for the relatively superior rate capability in SIBs to that in PIBs is the agile na~+diffusion with low energy barrier and moderate adsorption *** findings offer theoretical support for in-depth understanding of the performance differences of Cu-based materials in different ion storage systems.

关键词： Cu_(2)Se nanocubes DFT calculations Ion storage mechanism Potassium ion batteries Sodium ion batteries

Higher-order expansions of powered extremes of logarithmic general error distribution

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 47-54页

作者： tan Xiao-feng LI Li-hui School of Mathematics and Statistics Southwest UniversityChongqing 400715China

In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥***-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing *** is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v).

关键词： logarithmic general error distribution convergence rate higher-order expansion powered ex-treme

Facile preparation of Fe/n-based biomass porous carbon composite towards enhancing the thermal decomposition of DAP-4

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Defence Technology（防务技术） 2024年第1期31卷 288-294页

作者： Er-hai An Xiao-xia Li Cun-juan Yu Ying-xin tan Zi-jun Fan Qing-xia Li Peng Deng Xiong Cao School of Environment and Safety Engineering North University of ChinaTaiyuan030051PR China College of Safety and Emergency Management Engineering Taiyuan University of Science and TechnologyTaiyuan030024PR China

Fe/n-based biomass porous carbon composite(Fe/n-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/n-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was *** porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/n ***/np Carbon was prepared simply by the high-temperature carbonization *** was found that it showed the inherent catalysis properties for thermal decomposition of *** heat release of DAP-4/Fe/n-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/n-p *** decomposition temperature peak of DAP-4 at the presence of Fe/n-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/n-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/*** possible catalytic decomposition mechanism of DAP-4 with Fe/n-p Carbon was proposed.

关键词： Biomass materials Porous carbon DAP-4 Thermal decomposition Facile method

new Lump Solution and Their Interactions with n-Solitons for a Shallow Water Wave Equation

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Journal of Applied Mathematics and Physics 2024年第8期12卷 2836-2848页

作者： Yin Ji Xiyu tan College of Mathematics and Statistics Jishou University Jishou China

By employing the Hirota’s bilinear method and different test functions, the breather solutions of HSI equation with different structures are obtained based on symbolic calculation with perturbation parameters. Some new lump solitons are found in the process of studying the degradation behavior of breather solutions. The interaction between lump solution and soliton solution is constructed in the form of lump solution, and the motion trajectory of lump is obtained. In addition, the theorem of lump solitons and n-solitons superposition is given and proved. The superposition formula of lump is derived from the theorem, and its spatial evolution behavior is given.

关键词： HSI Equation Breather-Waves Lump Solutions Interaction Solution

Strong invariance principle for a counterbalanced random walk

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 370-380页

作者： tan Hui-qun HU Zhi-shui DOnG Liang International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China Center for Basic Teaching and Experiment Nanjing University of Science and TechnologyJiangyin 214443China

We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as *** n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n).

关键词： random walk martingale invariance principle

Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug nanosensor Application

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WOnG Yeong Yi F L Supian A Radzwan M Musa n F n Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHnS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor