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Science China chemistry 2024年第9期67卷 2982-2988页

作者： En-He Huang Li-Gao Liu You-Wei Yin Hao-Xuan Dong Ji-Jia Zhou Xin Lu Bo Zhou Long-Wu Ye key laboratory for chemical biology of fujian province and state key laboratory of physical chemistry of solid surfaces College of Chemistry and Chemical Engineering Xiamen University state key laboratory of Organometallic chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

α-Imino metal carbenes are versatile intermediates in organic synthesis, and have broad applications in the assembly of divergent N-heterocycles. However, the catalytic enantioselective desymmetrization based on α-imino metal carbenes has not been developed to date. Herein, we disclose an enantioselective desymmetrizing C（sp2）–H functionalization of azide-ynamides via α-imino copper carbenes, leading to the efficient assembly of divergent chiral indoloazepines in generally moderate to excellent yields with high enantioselectivities. Notably, this reaction represents the first enantioselective desymmetrization based on α-imino metal carbenes. Further synthetic transformations and biological tests show the potential utility of this method. Moreover,computational studies are employed to elucidate the reaction mechanism and the origin of enantioselectivity.

关键词： enantioselective desymmetrization metal carbenes copper catalysis nitrene transfer alkynes

Engineering and dynamics of heterogeneous catalysts via metal single atoms as promoters/precursors

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Science China chemistry 2024年第8期67卷 2547-2565页

作者： Jiwei Li Junli Xu Jingyun Yang Zitao Duan Zhun Zhang Haifeng Xiong state key laboratory of physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation laboratory for Sciences and Technologies of Energy Materials of fujian province Xiamen 361102China

Metal single-atom catalysts(SACs) have emerged as a focal point of research, captivating the scientific community due to their distinctive electronic properties and unparalleled catalytic prowess in the realm of heterogeneous catalysis. However, their significance transcends their role as mere active sites. Recent investigations have illuminated the multifaceted capabilities of metal single atoms as catalyst promoters and precursors, paving the way for the engineering of highly efficient heterogeneous catalysts. Single-atom promoters not only enhance the stabilization of active metals and tailor the support material, but regulate the reactive interfacial structure, eventually tuning the catalytic performance. Furthermore, SACs were also used as catalyst precursors to design new catalyst active sites. During the pretreatment or catalytic reaction, the structure of the metal single sites is changed significantly and transformed into the new and more active state, which improve the adsorption and reactive ability of reactants or intermediates. In this critical review, we comment the recent development of metal SACs used as catalyst promoters/precursors in engineering heterogeneous catalysts, including thermal catalysis and electrocatalysis. Furthermore, the dynamic evolution of the SACs during the pretreatment or catalytic reaction is also discussed. Finally, we provide our insight to potentially guide the future development on this emerging field.

关键词： single-atom catalysts single-atom promoter single-atom precursor dynamic evolution

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Linear paired electrolysis of furfural to furoic acid at both anode and cathode in a multiple redox mediated system

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Green Energy & Environment 2024年第1期9卷 104-113页

作者： Xinxin Li Linchuan Cong Haibo Lin Fangbing Liu Xiangxue Fu Hai-Chao Xu Nan Lin state key laboratory of Inorganic Synthesis and Preparative chemistry Jilin UniversityChangchun 130012JilinChina state key laboratory of physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the ***,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedﬂow cell *** reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are *** the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efﬁciency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects.

关键词： Multiple redox mediated system Linear paired electrolysis Furfural Furoic acid

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Single-cluster electronics using metallic clusters:Fabrications,regulations,and applications

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Nano Research 2024年第1期17卷 65-78页

作者： Caiyun Wei Wei Xu Shurui Ji Ruiyun Huang Junyang Liu Wenqiu Su Jie Bai Jiale Huang Wenjing Hong state key laboratory of physical chemistry of solid surfaces National Engineering Research Centre of Chemicals for Electronic ManufacturingCollege of Chemistry and Chemical Engineering&Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)Xiamen UniversityXiamen 361005China

Metallic clusters,ranging from 1 to 2 nm in size,have emerged as promising candidates for creating nanoelectronic devices at the single-cluster *** the intermediate quantum properties between metals and semiconductors,these metallic clusters offer an alternative pathway to silicon-based electronics and organic molecules for miniaturized electronics with dimensions below 5 *** progress has been made in studies of single-cluster electronic ***,a clear guide for selecting,synthesizing,and fabricating functional single-cluster electronic devices is still *** review article provides a comprehensive overview of single-cluster electronic devices,including the mechanisms of electron transport,the fabrication of devices,and the regulations of electron transport ***,we discuss the challenges and future directions for single-cluster electronic devices and their potential applications.

关键词： single-cluster junctions electronic properties electron transport metallic clusters structure regulation

Switching on/off phosphorescent or non-radiative channels by aggregation-induced quantum interference

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Aggregate

Aggregate 2024年第1期5卷 175-184页

作者： Yi Kong Yu-Chen Wang Xunkun Huang WanZhen Liang Yi Zhao Department of chemistry State Key Laboratory of Physical Chemistry of Solid SurfacesiChEMFujian Provincial Key Laboratory of Theoretical and Computational Chemistryand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenPeople’s Republic of China

Pure organic materials with persistent and efficient room-temperature phosphorescence have recently aroused great research interest due to their vast potential in *** crucial design principle for such materials is to suppress as much as possible the non-radiative decay of the triplet exciton while maintaining a moderate phosphorescent radiative ***,molecular engineering often exhibits similar regulation trends for the two ***,we propose that the quantum interference caused by aggregation can be utilized to control the phosphorescent and non-radiative decay *** systematically analyze various constructive and destructive transition pathways in aggregates with different molecular packing types and establish clear relationships between the luminescence characters and the signs of the singlet and triplet excitonic *** is shown that the decay channels can be flexibly switched on or off by regulating the packing type and excitonic *** importantly,an enhanced phosphorescent decay and a completely suppressed non-radiative decay can be simultaneously realized in the aggregate packed with inversion *** work lays the theoretical foundation for future experimental realization of quantum interference effects in phosphorescence.

关键词： excitonic coupling intersystem crossing organic aggregates organic room temperature phosphorescence quantum interference

Organic Brønsted Acid-Catalyzed Stereoselective Cationic RAFT Polymerization:The Effect of RAFT Agents

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Chinese Journal of Polymer Science 2024年第6期42卷 711-717页

作者： Zheng-Yi Zhang Zan Yang Yun Liao Sai-Hu Liao key laboratory of Molecule Synthesis and Function Discovery(fujian province University) College of ChemistryFuzhou UniversityFuzhou350108China state key laboratory of physical chemistry of solid surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing National laboratory for Molecular Sciences Beijing100190China

The tacticity of vinyl polymers is a key factor affecting the properties of ***,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products ***,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of *** this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the *** extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.

关键词： Bronsted acid catalysis Stereoselective cationic polymerization RAFT polymerization Chain transfer agents Tacticity

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Copper-catalyzed enantioselective desymmetrizing C（sp）–H functionalization of azide-ynamides via α-imino copper carbenes

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Science China chemistry 2024年

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Pd@Ir-LOD multienzyme utilizing endogenous lactate consumption cooperates with photothermal for tumor therapy

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Nano Research 2024年第1期17卷 270-281页

作者： Zichen Ye Yun Li Jingchao Li Xinyan Hu Jinyang Zheng Gongxin Zhang Sijin Xiang Tianbao Zhu Zhide Guo Xiaolan Chen state key laboratory for physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materials and Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China state key laboratory of Molecular Vaccinology and Molecular Diagnostics&Center for Molecular Imaging and Translational Medicine School of Public Health Xiamen UniversityXiamen 361102China The High Educational key laboratory for Biomedical Engineering&key laboratory of Fire Retardant Materials of fujian province Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361102China

Lactic acid(LA)plays a major role in the occurrence,development,and spread of *** by its high accumulation in tumor site,a novel lactate oxidase(LOD)conjugated two-dimensional Pd@Ir nanoplatform(Pd@Ir-LOD,PIL)was fabricated to combine cascade reaction with photothermal for tumor *** detail,the overexpressed LA in tumor microenvironment(TME)was a key factor to activate the PIL-based cascade reaction:(1)Plenty of H_(2)O_(2)could be generated from LA by the catalysis of LOD with O_(2);(2)potent·OH was produced from H_(2)O_(2)due to the peroxidase(POD)-like activity of PIL;(3)meantime,PIL’s catalase(CAT)-like activity could decompose part H_(2)O_(2)into O_(2)to achieve the purpose of LA cyclic ***,the reduced glutathione(GSH)scavenging capability of PIL might protect the produced reactive oxygen species(ROS)from being cleared to further improve the cascade therapeutic *** importantly,PIL had excellent photothermal conversion efficiency(37.35%)and manifested a surprising temperature rising effect in *** together,the decreasing LA concentration,accumulation of high-toxic ROS,the depletion of GSH together with the higher intra-tumoral temperature potently enhanced in vivo antitumor ***,a promising therapeutic tactic based on PIL integrating endogenous LA consumption,chemodynamic therapy(CDT),and photothermal therapy(PTT)has been put forward.

关键词： lactate oxidase chemodynamic therapy photothermal therapy cascade reaction tumor microenvironment

In situ tracking of the lithiation and sodiation process of disodium terephthalate as anodes for rechargeable batteries by Raman spectroscopy

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Nano Research 2024年第1期17卷 245-252页

作者： Xiu-Mei Lin Chong Han Xin-Tao Yang Jia-Sheng Lin Wei-Qiang Yang Hong-Xu Guo Yao-Hui Wang Jin-Chao Dong Jian-Feng Li Department of chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhou 363000China College of Energy College of Chemistry and Chemical EngineeringCollege of MaterialsState Key Laboratory of Physical Chemistry of Solid SurfacesiChEMXiamen UniversityXiamen 361005China Institute of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China

Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and *** terephthalate(Na_(2)C_(8)H_(4)O_(4),Na_(2)TP),an organic salt with a theoretical capacity of 255 mAh·g^(-1),is electroactive towards both lithium and ***,its electrochemical energy storage(EES)process has not been directly observed via in situ characterization techniques and the underlying mechanisms are still under ***,in situ Raman spectroscopy was employed to track the de/lithiation and de/sodiation processes of *** appearance and then disappearance of the–COOLi Raman band at 1625 cm^(-1) during the de/lithiation,and the increase and then decrease of the–COONa Raman band at 1615 cm^(-1) during the de/sodiation processes of Na2TP elucidate the one-step with the 2Li+or 2Na+transfer *** also found that the inferior cycling stability of Na2TP as an anode for sodium-ion batteries(SIBs)than lithium-ion batteries(LIBs)could be due to the larger ion radium of Na+than Li+,which results in larger steric resistance and polarization during *** Na2TP,therefore,shows greater changes in spectra during de/sodiation than de/*** expect that our findings could provide a reference for the rational design of organic compounds for EES.

关键词： disodium terephthalate(Na_(2)C_(8)H_(4)O_(4) Na2TP) in situ Raman spectroscopy de/lithiation de/sodiation mechanisms

CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

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Green Energy & Environment 2024年第7期9卷 1101-1111页

作者： Sen Ma Zheng Li Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng College of Energy State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University fujian Engineering and Research Centre of Clean and High-valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-valued Utilization of Biomass Centre for Green chemical Science University of Auckland

The conversion of biomass into sugar platform compounds is very important for the biorefinery industry. Pretreatment is essential to the biomass of the sugar platform, however, the lignin obtained by pretreatment, as a key part of lignocellulose, generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars. In this study, p-TsOH(p-toluenesulfonic acid), DES(Deep eutectic solvent) and CAOSA(cooking with active oxygen and solid alkali) pretreatment ways were used to fraction lignin from bamboo biomass. After CAOSA treatment, the hydrolysis efficiency of the pulp was 95.57%. Moreover, the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system. In this work, the results showed that CAOSA-extracted lignin with lower ?(1.31–1.25) had a better adsorption effect on the enzyme protein. p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis. In addition, the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

关键词： Biomass pretreatment CAOSA Cellulose hydrolysis Lignin Enzyme