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Converting Azine Linkage into Highly Stable(Thio)Urea-Based Bicyclic-Fused-Ring Connections in Covalent Organic Frameworks via Criss-Cross[3+2]Cycloaddition

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CCS Chemistry 2024年第9期6卷 2230-2240页

作者： Zhi-Bei Zhou Hui-Hui Sun Qiao-Yan Qi Xin Zhao Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic functional molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032

Exploring new linkage chemistry is of fundamental significance for covalent organic frameworks(COFs)to expand their structure and functional ***,we report a strategy for converting azine linkage into urea-and thiourea-based fused-ring connections in COFs by criss-cross[3+2]dipolar cycloaddition of azine with HNCO or *** as-prepared COFs with cyclized linkages exhibited enhanced chemical and thermal stability by locking the dynamic C=N linkages in the ***,functions could be introduced into the skeleton of COFs by this postsynthetic cyclization method,which enabled significant improvements in functionality,demonstrated by the studies on CO_(2)/N_(2) selective sorption,proton conduction,and Hg^(2+)*** use of this[3+2]cycloaddition strategy not only enriched the chemistry of linkage conversion for COFs but also offered a new way to fabricate fused-ring-linked COFs,thereby representing a high level of controllability on connectivity and functionality of COFs.

关键词： covalent organic frameworks linkage chemistry structural transformation [3+2]cycloaddition azine

Twisted Phosphors that Violate Kasha's Exciton Model in Organic Systems

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Chinese Journal of Chemistry 2024年第11期42卷 1237-1246页

作者： Boyi Fu Guangming Wang Jiuyang Li Junbo Li Xun Li Xiaoya Zhao Shuhui Ding Guoping Yan Qianqian Yan Kaka Zhang School of Materials Science and Engineering Wuhan Institute of TechnologyWuhanHubei430205 China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic functional molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China

Kasha's exciton model proposes that T1 energy levels of organic compounds are insensitive to molecular aggregation and microenvironment change because of negligible small transition dipole moments of T1 *** model holds true in most organic systems till *** we report the fabrication of twisted organic phosphors with intramolecular charge transfer characters and flexible molecular *** doped into different organic matrices,the twisted phosphor adopts different conformation,exhibits distinct phosphorescence colors and T1 energy levels,which violates Kasha's exciton model in organic *** that the change of phosphorescence colors and maxima can be readily distinguished by human eyes and conventional instrument,the twisted phosphors would be exploited as a new type of molecular probe,which would exhibit potential application in optical sensing and stimuli-responsive systems.

关键词： Afterglow Twisted phosphor Triplet excited state Room-temperature phosphorescence Luminescence Spin-orbit coupling

The Mn/Yb/Er triple-doped CeO_(2) nanozyme with enhanced oxidase-like activity for highly sensitive ratiometric detection of nitrite

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Chinese Chemical Letters 2024年第6期35卷 491-495页

作者： Simin Wei Yaqing Yang Junjie Li Jialin Wang Jinlu Tang Ningning Wang Zhaohui Li College of Chemistry Institute of Analytical Chemistry for Life ScienceHenan Joint International Research Laboratory of Green Construction of Functional Molecules and their Bioanalytical ApplicationsZhengzhou UniversityZhengzhou 450001China School of Basic Medical Sciences Zhengzhou UniversityZhengzhou 450001China

Long-term excessive intake of nitrite(NO_(2)^(-))poses a great threat to human health,needing a simple and fast method to detect NO_(2)-in ***,via a simple and feasible strategy,Mn/Yb/Er triple-doped CeO_(2) nanozyme(Mn/Yb/Er/CeO_(2))was synthesized for highly sensitive ratiometric detection of *** doping Mn,Yb,Er into CeO_(2) lattice structure,Mn/Yb/Er/CeO_(2) nanozyme showed enhanced oxidase-like activity,obtaining a higher density of oxygen vacancy and a higher ratio of Ce^(3+)to Ce~(4+)than that of CeO_(2).The 3,3,5,5-tetramethylbenzidine(TMB)can be effectively oxidized by Mn/Yb/Er/CeO_(2) to produce the oxidized TMB(ox TMB),showing a significant absorption signal at 652 ***,nitrite can react with ox TMB to produce yellow diazotized ox TMB,which is accompanied by an elevated absorption signal at 445 nm and a decreased absorption signal at 652 ***,based on the oxidase-mimetic activity of Mn/Yb/Er/CeO_(2) and the diazotization reaction between NO_(2)^(-)and ox TMB,a ratiometric colorimetric assay was established for NO_(2)^(-)detection in ***,by integrating Mn/Yb/Er/CeO_(2) with a smartphone,a colorimetric smartphone-sensing platform was successfully fabricated for visualization and quantitative detection of NO_(2)^(-).Notably,this two-detection mode showed excellent sensitivity,selectivity,reliability and practicability in monitoring the NO_(2)^(-)in real samples,impling its great potential for food safety.

关键词： Mn/Yb/Er/CeO_(2) nanozyme Oxidase-like activity Nitrite Ratiometric detection Two-detection mode

Ordered mesoporous nanofibers mimicking vascular bundles for lithium metal batteries

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National Science Review 2024年第5期11卷 291-302页

作者： Xiaohang Zhu Mengmeng Liu Fanxing Bu Xin-Yang Yue Xiang Fei Yong-Ning Zhou Anqi Ju Jianping Yang Pengpeng Qiu Qi Xiao Chao Lin Wan Jiang Lianjun Wang Xiaopeng Li Wei Luo State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Institute of Functional Materials College of Materials Science and Engineering Donghua University institute for Conservation of Cultural Heritage Shanghai University Frontiers Science Center for Transformative molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong University Department of Materials Science Fudan University

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene（PS） homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

关键词： ordered mesoporous nanofibers electrospinning oriented micelles lithium metal batteries

Rhodium-catalyzed addition reactions of benzylic C–H bonds to cyclic N-sulfonyl ketimines viaπ-coordination

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Chinese Chemical Letters 2024年第3期35卷 287-291页

作者： Yuntong Li Hang Shi Department of Chemistry Zhejiang UniversityHangzhou 310027China Key Laboratory of Precise Synthesis of functional molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and ***,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic *** this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-*** strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.

关键词： Benzylic deprotonation Cyclic N–sulfonyl ketimines π-Coordination Mannich-type addition Rhodium catalysis

Operando NMR methods for studying electrocatalysis

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Magnetic Resonance Letters 2024年第2期4卷 54-64页

作者： Zhiyu Zhu Ruipeng Luo Evan Wenbo Zhao Magnetic Resonance Research Center Institute for Molecules and MaterialsRadboud University6525 AJ Nijmegenthe Netherlands

The combination of electrochemical measurements with spectroscopic characterizations provides valuable insights into reaction *** magnetic resonance(NMR)spectroscopy,as a powerful technique due to its atomic specificity and versatility in studying gas,liquid,and solid,allows the study of electrolyte solution,catalyst and catalyst-adsorbate *** applied in operando,NMR can offer molecular-level insights into various electrochemical *** NMR has been applied extensively in battery research,but relatively underexplored for electrocatalysis in the past two *** this mini review,we first introduce the operando electrochemical NMR setups,categorized by different probe *** we review the applications of operando NMR for monitoring the electrolyte solution and the catalyst-adsorbate *** the high environmental impact of electrochemical conversion of CO_(2)into value-added products,we zoom in to the use of operando NMR in studying electrochemical CO_(2)***,we provide our perspective on further developing and applying operando NMR methods for understanding the complex reaction network of Cu-catalyzed electrochemical CO_(2)reduction.

关键词： Operando NMR In situ NMR EC-NMR Electrocatalysis Electrochemical CO_(2)reduction

Asymmetric side-chain engineering of organic semiconductor for ultrasensitive gas sensing

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Chinese Chemical Letters 2024年第3期35卷 428-433页

作者： Xiaoying Ma Xiaojuan Dai Lanyi Xiang Jiajun Chang Danfeng Zhi Haozhen Zhao Zhenjie Ni Ye Zou Xike Gao Fengjiao Zhang School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Laboratory of Organic Solids Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic functional molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Binzhou institute of Technology Binzhou 256606China

Molecular structure of organic semiconductor plays a critical role in determining the performance and functionality of organic electronic devices,by optimizing the electrical,optical and physicochemical *** alkyl chains are fundamental units in tailering the solubility and assemblability,among which the asymmetric properties have been reported as key element for controlling the packing motifs and intrinsic charge ***,we expanded the scope of molecular asymmetry dependent sensing features based on a new series of naphthalene diimides(NDI)-based derivatives substituted with a same branching alkyl chain but various linear-shaped alkyl chains(Cn-).A clear molecular stacking change,from head-to-head bilayer to head-to-tail monolayer packing model,is observed based on the features of anisotropic molecular interactions with the change in the chain *** importantly,a unique LUMO level shift of 0.17 eV is validated for NDI-PhC4,providing a record sensitivity up to 150%to 0.01 ppb ammonia,due to the desired molecular reactivity and device amplification *** results indicate that asymmetric side-chain engineering opens a route for breath healthcare.

关键词： Organic thin film transistor Asymmetric side chain Gas sensing Molecular stacking Energy level manipulating

Subnanometric bimetallic Pt-Pd clusters in zeolites for efficient hydrogen production and selective tandem hydrogenation of nitroarenes

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Science China Chemistry 2024年第9期67卷 2911-2917页

作者： Jiafu Li Tao Cai Yanran Feng Xia Liu Ning Wang Qiming Sun institute of Sustainable Energy and Resources College of Chemistry and Chemical EngineeringKey Laboratory of Shandong Provincial Universities for Functional Molecules and MaterialsQingdao UniversityQingdao 266071China Innovation Center for Chemical Sciences College of ChemistryChemical Engineering and Materials ScienceJiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhou 215123China

The solvolysis of ammonia borane(AB)and the hydrogenation of nitroarenes represent significant reactions for hydrogen generation and value-added chemical *** strategic engineering of the catalysts is imperative for surmounting obstacles associated with their stability and catalytic *** this work,subnanometric bimetallic Pt–Pd clusters were encapsulated within silicalite-1(S-1)zeolites through a ligand-protected in-situ hydrothermal synthesis *** synergetic effect of bimetallic composition and zeolite confinement markedly enhances the catalytic performance of representative Pt_(0.5)Pd_(0.5)@S-1-H catalyst,affording exceptional turnover frequency(TOF)values of 1,043 and 573 mol_(H_(2))mol_(metal)^(-1)min^(-1)for AB hydrolysis and methanolysis at ambient conditions,respectively,surpassing most of the state-of-the-art Pt-based *** and isotopic experiments reveal that the bimetallic catalytic system remarkably boosts the O-H cleavage of water,thereby facilitating the H_(2) production from AB ***,a conspicuous synergistic effect is demonstrated in the shape-selective tandem hydrogenation of nitroarenes,with the bimetallic catalyst facilitating both AB hydrolysis and nitroarene hydrogenation,giving a high TOF value of 1,260 h^(-1)under atmospheric *** study not only demonstrates the effectiveness of bimetallic nanocatalysts encapsulated in zeolites for hydrogen production from chemical hydrogen storage materials,but also paves the way for the design of catalysts with multifunctional active sites capable of synergistically promoting tandem catalytic processes.

关键词： subnanometer bimetallic cluster zeolite synergistic effect ammonia borane solvolysis selective tandem hydrogenation

Cucurbit[n]uril-based nanostructure construction and modification

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Chinese Chemical Letters 2024年第8期35卷 138-148页

作者： Lijun Mao Shuo Li Xin Zhang Zhan-Ting Li Da Ma School of Pharmaceutical Engineering&institute for Advanced Studies Taizhou UniversityJiaojiang 318000China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic functional molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438China

New fabrication method of nanostructures is of great importance for the applications of nanoscience and *** review summarizes cucurbit[n]uril(CB[n])-based nanostructure fabrication and modification *** strategies include the use of CB[n]s as building blocks and supramolecular crosslinkers to fabricate nanostructures,to surface modify nanostructures,and as gatekeepers to control the release of encapsulated *** nanostructures are used for drug delivery,bioimaging,chemical sensing,catalysis and other ***[n]s often play a vital role in the fabrication of these nanos-tructures,and the realization of the applications.

关键词： Cucurbit[n]uril Nanostructure Host-guest interaction Nanofabrication