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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu Chen Jie Li Chen Zhu key laboratory of organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China

We report a novel cyano migration-mediated radical-polar crossover process,whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently *** transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic *** studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution,leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Carbon Dots-Modified Hollow Mesoporous Photonic Crystal Materials for Sensitivityand Selectivity-Enhanced Sensing of Chloroform Vapor

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Nano-Micro Letters 2025年第4期17卷 381-398页

作者： Junchen Liu Ji Liu Zhipeng Li Liupeng Zhao Tianshuang Wang Xu Yan Fangmeng Liu Xiaomin Li Qin Li Peng Sun Geyu Lu Dongyuan Zhao State laboratory On Integrated optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China Department of Chemistry and laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of PolymersCollaborative Innovation Center of Chemistry for Energy Materials(2011-iChEM)College of Chemistry and MaterialsFudan UniversityShanghaiPeople’s Republic of China School of engineering and Built Environment Griffith UniversityNathanQLD 4111Australia

Chloroform and other volatile organic pollutants have garnered widespread attention from the public and researchers,because of their potential harm to the respiratory system,nervous system,skin,and ***,research on chloroform vapor sensing is still in its early stages,primarily due to the lack of specific recognition *** we report a mesoporous photonic crystal sensor incorporating carbon dots-based nanoreceptor(HMSS@CDs-PCs)for enhanced chloroform *** colloidal PC packed with hollow mesoporous silica spheres provides an interconnected ordered macro-meso-hierarchical porous structure,ideal for rapid gas sensing utilizing the photonic bandgap shift as the readout *** as-synthesized CDs with pyridinic-N-oxide functional groups adsorbed in the hollow mesoporous silica spheres are found to not only serve as the chloroform adsorption sites,but also a molecular glue that prevents crack formation in the colloidal *** sensitivity of HMSS@CDs-PCs sensor is 0.79 nm ppm^(-1)and an impressively low limit of detection is 3.22 ppm,which are the best reported values in fast-response chloroform vapor sensor without multi-signal *** positive response time is 7.5 s and the negative response time 9 ***,relatively stable sensing can be maintained within a relative humidity of 20%-85%RH and temperature of 25-55℃.This study demonstrates that HMSS@CDs-PCs sensors have practical application potential in indoor and outdoor chloroform vapor detection.

关键词： Carbon dots Photonic crystal sensors Sensitivity-enhanced sensing Selectivity-enhanced sensing Chloroform vapor sensing

Synergistic BrΦnsted/Lewis acid catalyzed atroposelective synthesis of aryl-β-naphthol

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Chinese Chemical Letters 2025年第1期36卷 293-298页

作者： Jiajun Lu Zhehui Liao Tongxiang Cao Shifa Zhu key laboratory of Functional molecular engineering of Guang-dong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical engineering Zhejiang Sci-Tech UniversityHangzhou 310018China State key laboratory of Elemento-organic Chemistry Nankai UniversityTianjin 300071China

Axially chiral binaphthol have achieved great success in asymmetric *** toα-binaphthol,axially chiral aryl-β-naphthol are far less ***,we report a method of asymmetric catalysis to constructβ-naphthol with up to 99%yield,95.5:4.5 enantiomeric ratio,using alkynyl esters as precursors and chiral phosphonic acid(CPA)/Lewis acid as *** steps involve oxygen transfer and de novo arene formation to set up the chiral ***,this methodology provides a versatile platform for structurally divergent synthesis of atroposelectiveβ-naphthol analogs,which are widely found in bioactive molecules and asymmetric catalysts.

关键词： Synergistic catalysis Atropisomerism Aryl-β-naphthol Enantioselectivity Tandem reaction

Classification and progress of extraction technologies for nonferrous metal resources

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Science China Chemistry 2025年第2期68卷 458-474页

作者： Fangqin Cheng Na Zhou Nazeer Muhammad Nouman Li Cui Caixia Yin Institute of Resources and Environmental engineering State Environmental Protection Key Laboratory of Efficient Utilization of Coal Waste ResourcesShanxi UniversityTaiyuan 030006China key laboratory of Chemical Biology and molecular engineering of Ministry of Education Institute of Molecular ScienceShanxi UniversityTaiyuan 030006China

In recent years,the demand for strategic metal resources,essential for scientific and technological progress and industrial development,has *** a stable supply of these metals is critical to national security and the well-being of the *** global industrialization accelerates,the daily demand for nonferrous metals continues to ***,extracting and recovering strategic metals from low-grade raw materials,such as solid waste,has become crucial for maintaining their supply and economic ***,the extraction process is fraught with challenges,including mineral phase stability and complex *** review focuses on key strategic metals such as lithium,aluminum,gallium,and *** introduces and examines various methods for extracting nonferrous metals from different raw materials,including traditional mining technologies applied to low-grade solid *** also outlines future development opportunities and challenges in this field.

关键词： nonferrous metal extraction classification and progress

Uncovering fantastic synergistic lithium adsorption with manganese-titanium based composite nanospheres:Mild synthesis and molecular dynamics simulation insights

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Journal of Energy Chemistry 2025年第2期101卷 52-67页

作者： Yameng Wang Zi-Yu Liu Yubei Su Yu Liu Aoqun Liu Xiaoye Zhang Yugang Huang Liyun Zhang Haisheng Chen Wancheng Zhu Department of Chemical engineering Qufu Normal University Institute of engineering Thermophysics Chinese Academy of Sciences State key laboratory of organic-Inorganic Composites Beijing University of Chemical Technology

In light of the burgeoning energy technology sector and the ever-growing demand for lithium across diverse industrial domains,conventional lithium extraction methods have been proven inadequate due to their limited production capacity and high operational *** work introduces a novel approach to the manganese-titanium based composite HMTO（Mn:Ti=1:4） lithium ion-sieve（LIS） nanospheres,employing lithium acetate dihydrate,manganese carbonate and titanium dioxide P25 as the primary *** nanospheres exhibit relatively uniform spherical morphology,narrow size distribution,small average particle size（ca.55 nm）,large specific surface area(43.58 m2g-1) and high surface O2-content（59.01%）.When utilized as the adsorbents for Li+ions,the HMTO（Mn:Ti=1:4） LIS demonstrates a fast adsorption rate,approaching equilibrium within 6.0 h with an equilibrium adsorption capacity（qe）of 79.5 mg g-1and a maximum adsorption capacity（qm） of 87.26 mg g-1(initial concentration CO:1.8 g L-1).In addition,the HMTO（Mn:Ti=1:4） also delivers a high lithium extraction from the simulated high magnesium-lithium molar ratio salt lake brine（Mg:Li=103）,achieving a qeof 33.85 mg g-1along with a remarkable selectivity(αMgLi=2192.76).Particularly,the HMTO（Mn:Ti=1:4） LIS showcases a satisfactory recycling adsorption *** adsorption capacity remains at a high level,even that determined after the 5th cycle(55.45 mg g-1) surpasses that of the most recently reported ***,the fantastic synergistic lithium adsorption mechanism is deliberately uncovered by leveraging the ion exchange principles and molecular dynamics（MD） simulations.

关键词： Adsorption performance Ion exchange Lithium ion-sieves Manganese titanium composite Salt lake brine lithium extraction

Cocrystals of axially N-embedded quasi-carbon nanohoops via modulating the electron affinity of guest acceptors

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Science China Chemistry 2025年

作者： Li Zhang Shuhai Qiu Shunlong Hu Hanren Xu Xuwen Sun Wei Jiang Da-Hui Qu Zhaohui Wang key laboratory for Advanced Materials and Joint International Research laboratory of Precision Chemistry and molecular engineering Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materi-obiology and Dynamic Chemistry Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology key laboratory of organic optoelectronics and molecular engineering Department of Chemistry Tsinghua University

organic donor-acceptor cocrystals of π-conjugated molecues have shown diverse applications in materials science. However,most cocrystals exist in neutral forms dominated by π-π interactions, while the ionic congeners and corresponding properties are rarely studied due to difficulties in harnessing the degree of charge transfer. Herein, we report cocrystals of axially N-embedded quasi-carbon nanohoops(DPP-D and DPP-T) with electron deficient guests. By modulating the electron affinity of the acceptor guests, the electronic structures of the complexes can be tuned from neutral to ionic states. Specifically, DPP-D interacts with TCNB molecules to form neutral superstructures via intermolecular π-π interactions, giving rise to a deep-red emission in the solid state. In contrast, an ionic complex showing near-infrared region absorptions and paramagnetic character on account of strong charge-transfer interactions is generated when DDQ molecules are involved. Their unique properties can be explained by different degrees of charge transfer and assembly modes, which have clearly been manifested by crystal structures and theoretical calculations. Our studies provide rare examples of π-conjugated macrocycle-based donor-acceptor cocrystals in both neutral and ionic forms, and give insight to the design of multicomponent carbon nanomaterials.

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Upcycling of polyphenylene oxide into 2,6-dimethyl aniline via depolymerization and amination over a Pt/CeO_(2) catalyst

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Science China Chemistry 2025年第2期68卷 520-525页

作者： Shengchao Jia Wenke Zhao Xiaohui Liu Yong Guo Yanqin Wang State key laboratory of Green Chemical engineering and Industrial Catalysis Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai key laboratory of Functional Materials Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Upcycling of plastic waste into N-containing compound is a novel and attractive strategy for its disposal and will opens up a promising direction for the production of value-added ***,an efficient strategy for the depolymerization-amination of polyphenylene oxide(PPO)into 2,6-dimethyl aniline is developed over a simple Pt/CeO_(2) *** C–O linkages of PPO can be selectively broken,producing 2,6-dimethyl phenol and then hydrogenated and aminated to 2,6-dimethyl cyclohexylamine over the Pt/CeO_(2) ***,2,6-dimethyl aniline was produced with high selectivity through the dehydrogenation of 2,6-dimethyl cyclohexylamine in the same *** can be used as the hydrogen-acceptor in the dehydrogenation step and enhance the selectivity of target *** N-containing compound,2,6-dimethyl aniline,is obtained and separated after HCl ***,the Pt/CeO_(2) catalyst exhibit remarkable stability and can sustainably catalyze the synthesis of 2,6-dimethyl aniline in several cycles.

关键词： PPO depolymerization-amination 2,6-dimethyl aniline Pt/CeO_(2)

CO_(2)-mediated bicarbonate conversion to concentrated formate in a CEM-based electrolyzer

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Journal of Energy Chemistry 2025年第1期100卷 605-611页

作者： Haocheng Xiong Donghuan Wu Haonan Li Andrew Li Qikun Hu Siyao Song Bingjun Xu Qi Lu State key laboratory of Chemical engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China College of Chemistry and molecular engineering Peking UniversityBeijing 100871China Ordos laboratory Inner Mongolia 017000China

Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO_(2)emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO_(2)using alkaline solutions with reactive *** this work,we present a CO_(2)-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm^(2)electrode *** electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended *** techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.

关键词： Electrocatalysis Techno-economic assessments Electrochemistry Flow electrolyzer

Enantioselective copper-catalyzed dearomative borylative cyclization of indoles and mechanistic insights

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Science China Chemistry 2025年第2期68卷 670-678页

作者： Yanfei Li Xuetao Li Zheng Zhang Yiliang Zhang Xiuping Yuan Jianjun Yin Simin Wang Wei Guan Qian Zhang Tao Xiong Jilin Province key laboratory of organic Functional molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Functional Material Chemistry Department of ChemistryNortheast Normal UniversityChangchun 130024China State key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical engineering Harbin Normal UniversityHarbin 150025China

Alicyclic nitrogen heterocycles,such as enantioenriched polycyclic fused[1,2-a]indoline derivatives,are widespread in natural products,agrochemicals and pharmaceutical *** methods predominantly rely on the recent emerging Heck-type catalytic asymmetric dearomatization(CADA)protocol,wherein noble palladium catalysts commonly necessitate the form arylPd species-triggered these *** contrast,a more sustainable base metal catalysis paradigm through alkyl metal species disrupting the aromaticity,that is,the utilization of challenging asymmetric Csp3–Csp3 bond formation entry to such important chiral densely functionalized polycyclic molecular scaffolds,remains an elusive ***,we report the first copper-catalyzed dearomative borylative cyclization of indoles under mild reaction conditions,affording an array of valuable Bpin-containing pyrrolo-fused[1,2-a]indolines bearing four consecutive stereogenic centers with excellent enantioand *** synthetic potential was documented via an array of useful *** functional theory(DFT)calculation studies elucidated the origin of the chemo-,regio-,enantio-and diastereoselectivities of this conversion.

关键词： copper catalysis dearomatization borylative cyclization indoles DFT calculations