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Science China chemistry 2024年第2期67卷 542-550页

作者： Min Chen Longqing Yang Yuzhen Li Yinhe Qu Guihua Pan Xiaoming Feng Xiaohua Liu Key Laboratory of Green chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed,which exhibits good functional group compatibility,high atomic and step *** protocol utilizes a strategy of synergistic catalysis with a chiral N,N'-dioxide/Ni~Ⅱ complex and an achiral Pd~0 catalyst,generating a series of multisubstituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-,Z/E-and enantioselectivity under mild *** transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product *** studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E-and *** density functional theory(DFT) calculations further demonstrated that multiple C–H···π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state.

关键词： asymmetric allylic alkylation synergistic catalysis vinyl epoxides allyl alcohol multiple weak interactions

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China chemistry 2024年第6期67卷 1935-1940页

作者： Ya-Ping Shao Zhuo-Min Chi Yong-Min Liang State Key Laboratory of Applied Organic chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

Photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na

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Science China chemistry 2024年第2期67卷 587-594页

作者： Fangming Chen Lvqi Jiang Chunyang Hu Jie Liu Wenbin Yi School of chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Organofluorine chemistry Shanghai Institute Organic ChemistryChinese Academy of SciencesShanghai200032China

Since the first report of sodium trifluoromethanesulfinate(CF_(3)SO_(2)Na) as an electrophilic trifluoromethylthiolation reagent in 2015,there has been no breakthrough in research in this ***,we disclose an unprecedented usage of CF_(3)SO_(2)Na as a radical trifluoromethylthiolation reagent.A photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na in the presence of PPh_(3) and catalytic copper has been ***,either Ir[(p-Fppy)_(2)(bpy)]PF_6 or Ir(ppy)_(3) could facilitate this *** studies indicate that initiation of the radical chain proceeded via two different photocatalytic quenching *** protocol provides a practical method for the construction of diverse vicinal ditrifluoromethylthiolated compounds.

关键词： trifluoromethylthiolation photocatalysis radical difunctionalization alkenes

Energy transfer, anticounterfeiting, white light emission and sensing in fine-regulating series of lanthanide metal-organic frameworks

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Journal of Rare Earths 2024年第3期42卷 446-454,I0001页

作者： Juanjuan Xue Yao Wang Guoping Yang Yaoyu Wang Key Laboratory of Synthetic and Natural Functional Molecule chemistry of the Ministry of Education Shaanxi Key Laboratory of Physico-Inorganic ChemistryCollege of Chemistry&Materials ScienceNorthwest UniversityXi'an710127China

Three lanthanide ions and a rigid(1,1'-biphenyl)-2,4,6-tricarboxylic acid(H_(3)bptc) ligand led to the isostructural lanthanide metal-organic frameworks(Ln-MOFs) {[Ln(bptc)(H_(2)O)_(3)]·3H_(2)O}_n(Lnbptc, Ln = Eu,Tb, Gd, Eu_(x)Tb_(1—x), Eu_(x)Gd_(1-x), Tb_(x)Gd_(1-x), and Eu_(0.12)Tb_(0.52)Gd_(0.36)). The density functional theory(DFT) and time-dependent DFT calculation were expanded on H_3bptc, which point to the occurrence of “antenna effect”. The minor diameter samples of Eubptc, Tbbptc, and Gdbptc can also be attained via the microwave synthesis and employed for handwriting anticounterfeiting. Interestingly, the typical red emission of Eu^(3+) and green emission of Tb~(3+) could be fine-tuned by Gd^(3+) via chemical mixing to be full-color emissions bimetallic doped Eu_(x)Tb_(1-x)bptc, Eu_(x)Gd_(1-x)bptc, and Tb_(x)Gd_(1-x)bptc. The above synthetic bimetallic MOFs can be fixed in positioning boxes of quick response(QR) codes with diverse emission for anticounterfeiting. The message can be decoded under the irradiation of 365 nm ultraviolet lamp while invisible in the daylight. Notably, the trimetallic doped Eu_(0.12)Tb_(0.52)Gd_(0.36)bptc emits white light with the CIE color coordinate(0.34, 0.34). Furthermore, Tbbptc is demonstrated to be a sensitive probe toward nitrobenzene and acetone with multiple mechanisms.

关键词： Metal-organic frameworks Anticounterfeiting White light-emitting Sensing Rare earths

Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

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Digital Communications and Networks 2024年第1期10卷 38-44页

作者： Mianjie Li Senfeng Lai Jiao Wang Zhihong Tian Nadra Guizani Xiaojiang Du Chun Shan School of Electronics and Information Guangdong Polytechnic Normal UniversityGuangzhou510665China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China schoolof Electrical Engineering and Computer Science Washington State UniversityPullmanWA99164USA Department of Computer and Information Science Temple UniversityPhiladelphiaPA19122USA

Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication *** that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of *** multiwatermarking process employs spread transform dither *** the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading ***,multiple watermarks can be simultaneously embedded into the same position of a multimedia ***,the multiple watermarks can be extracted without affecting one another during the extraction *** analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.

关键词： B5G Multimedia information security Spread transform dither modulation Spreading vector measurement Unit maximum capacity

Surfactant-metal-organic framework complexes and their derivatives: advances in electrocatalysis

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Science China chemistry 2024年第10期67卷 3209-3222页

作者： Yining Liu Mengying Wang Zuozhong Liang Haoquan Zheng Key Laboratory of Applied Surface and Colloid chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal University

Metal-organic frameworks(MOFs) and their derivatives received more and more attention due to the diverse morphologies, rich porous structures, and tunable metal active sites, which have been widely used in energy-related electrocatalytic ***, a class of compounds with hydrophilic and hydrophobic portions in the molecular structure, are able to modulate the properties of liquid and solid surfaces. Surfactants play a crucial role in controlling the shape and size of MOFs, which helps optimize electrocatalytic performance, especially in improving the exposure and accessibility of catalytic active sites. In this review, we first outline the types and applications of surfactants. Second, we describe the interface modulation and reaction mechanism of different surfactants during the forming of MOFs and their derivatives. Finally, we discuss the current applications of surfactant-modified MOFs and their derivatives in electrocatalysis. This review provides a better understanding of surfactantassistant structure regulation and electrocatalytic activity study of MOFs and their derivatives.

关键词： metal-organic frameworks surfactants interface modulation electrocatalysis

Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China chemistry 2024年第7期67卷 2257-2264页

作者： Shi-Quan Song Xiao Han Zhong-Zhong Huo Ching-Fai Yip Xian-Fang Hong Meng-Ning Ding You-Xuan Zheng State Key Laboratory of Coordination chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)***,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these ***,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,*** addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,*** based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,*** importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

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

Quantitative lithium substitution of carboxyl hydrogens in polyacrylic acid binder enables robust SiO electrodes with durable lithium storage stability

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Journal of Energy chemistry 2024年第10期97卷 352-360页

作者： Weihua Wang Wenyi Li Siyi Jing Huiping Yang Huiqun Wang Ling Huang Yuxiang Mao Xikun Pang Yudai Huang Li Zhang State Key Laboratory of Physical chemistry of Solid Surfaces Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy Materials (iChEM) Xiamen University State Key Laboratory of chemistry and Utilization of Carbon-Based Energy Resources College of Chemistry Xinjiang University

The design of advanced binders plays a critical role in stabilizing the cycling performance of large-volume-effect silicon monoxide（SiO） *** the classic polyacrylic acid（PAA） binder,the self-association of-COOH groups in PAA leads to the formation of intramolecular and intermolecular hydrogen bonds,greatly weakening the bonding force of the binder to SiO ***,strengthening the binder-material interaction from the perspective of binder molecular regulation poses a significant ***,a modified PAA-Lix（0.25 ≤x≤1） binder with prominent mechanical properties and adhesion strength is specifically synthesized for SiO anodes by quantitatively substituting the carboxylic hydrogen with *** appropriate lithium substitution（x=0.25） not only effectively increases the number of hydrogen bonds between the PAA binder and SiO surface owing to charge repulsion effect between ions,but also guarantees moderate entanglement between PAA-Lixmolecular chains through the ion-dipole *** such,the PAA-Li0.25/SiO electrode exhibits exceptional mechanical properties and the lowest volume change,as well as the optimum cycling(1237.3 mA h g-1after 100cycles at 0.1 C) and rate performance(1000.6 mA h g-1at 1 C),significantly outperforming the electrode using pristine PAA *** work paves the way for quantitative regulation of binders at the molecular level.

关键词： Adhesion strength Charge repulsion effect Polyacrylic acid binder Quantitative lithium substitution SiO anode

Evolution exploration and structure prediction of Keggin-type group IVB metal-oxo clusters

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Chinese Chemical Letters 2024年第5期35卷 487-492页

作者： Run-Han Li Tian-Yi Dang Wei Guan Jiang Liu Ya-Qian Lan Zhong-Min Su School of chemistry South China Normal UniversityGuangzhou 510006China Institute of Functional Material chemistry Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Theoretical chemistry Jilin UniversityChangchun 130023China

The fascinating chemical structure and broad application prospect of Keggin-type polyoxometalates(POMs)have attracted many chemists to explore and discover *** the traditional Keggin,larger metal atomic radius,higher metal coordinated numbers,lower metal valence states and other features allow the group IVB metal-based Keggin(IVB-Keggin)more space and unknown in terms of structure and ***,density functional theory(DFT)calculations were performed to explore the influences including cores,shells,caps,and terminal ligands,et *** IVB-Keggin,and analyze the possibility of novel structure *** the perspective of multi-layer onion-like clusters,molecular energy level,host-guest interaction energy,surface charge and covalent bond polarity can be further adjusted to achieve the oriented design of functional *** insights are expected to provide theoretical support for experimental synthesis,opening a new perspective to understand the growth of Keggin.

关键词： Keggin Metal-oxo clusters Group IVB Onion pattern DFT