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Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-Shuo Bao Zi-Wei He Wen-Jing Xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China key laboratory of organo-pharmaceutical chemistry of Jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China chemistry 2024年

作者： Wen-Yuan Qu Xue-Song Zhou Wen-Jing Xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of Chemistry Central China Normal University Wuhan Institute of Photochemistry and Technology key laboratory of organo-pharmaceutical chemistry of Jiangxi Province Gannan Normal University

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

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Visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)

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Chinese Chemical Letters 2024年第7期35卷 281-284页

作者： Tian-Yu Gao Xiao-Yan Mo Shu-Rong Zhang Yuan-Xu Jiang Shu-Ping Luo Jian-Heng Ye Da-Gang Yu key laboratory of Green chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China State key laboratory Breeding Base of Green chemistry-Synthesis Technology Zhejiang University of TechnologyHangzhou 310014China State key laboratory of Elemento-Organic chemistry Nankai UniversityTianjin 300071China

Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.

关键词： Carbon dioxide Epoxides Visible-light photoredox catalysis Hydroxy acid Sequential single electron transfer

Anion-induced electrolyte chemistry enables high energy density primary battery for ultralow-temperature conditions

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Science China chemistry 2024年

作者： Zi-Hang Xue Hao-Jie Liang Yong-Li Heng Jia-Lin Yang Edison Huixiang Ang Hong-Yan Lü Hong Yu Dong-Mei Dai Dai-Huo Liu Chuan-Yu Zheng Wei Guo Xing-Long Wu Department of chemistry Northeast Normal University MOE key laboratory for UV Light-Emitting Materials and Technology Northeast Normal University Natural Sciences and Science Education National Institute of Education Nanyang Technological University State key laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University School of chemistry and Chemical Engineering Henan Normal University key laboratory of organo-pharmaceutical chemistry of Jiangxi Province Gannan Normal University

Lithium/fluorinated-carbon（Li/CFx） primary batteries are widely used in defense and military fields due to their stable discharge plateau, low self-discharge rate, and adaptability across a wide temperature range. However, enhancing their overall energy density and discharge capacity at low temperatures remains a critical challenge. Herein, we report a strategically designed LiBF4-based sulfite/carboxylate electrolyte, where the anion-involved solvation structure significantly enhances electrochemical kinetics by reducing the desolvation barrier. Simultaneously, it introduces a radical reaction mechanism that contributes to additional capacity. As a result, the Li/CFxprimary batteries with this formulated electrolyte deliver a specific capacity of 2,257.15 mAh g-1at 25 °C. More importantly, when operating at -40 °C, the batteries exhibit an exceptionally high discharge capacity of 1,549.4 m Ah g-1and an energy density of 2,868.6 Wh kg-1. Even at -60 °C, the Li/CFxcells achieve a specific capacity of 444.3 mAh g-1and an energy density of 821.8 Wh kg-1at 0.1 C, significantly outperforming previously reported organic-based liquid electrolytes. This work offers a viable strategy for enhancing the specific capacity and energy density of primary batteries in extreme environments, providing valuable insights for future developments.

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Activity promotion of Rh_(1)Ca_(x)/Al_(2)O_(3) single-atom catalyst in 1-octene hydroformylation:a volcano curve exists between Ca adding ratio and catalytic activity

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Science China chemistry 2024年第4期67卷 1187-1192页

作者： Hao Zhang Xingcong Zhang Xilun Wang Qingdi Sun Hao Liu Hongbing Ji Xiaohui He key laboratory of Bioinorganic and Synthetic chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of ChemistryIGCMESun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China State key laboratory Breeding Base of Green-Chemical Synthesis Technology Institute of Green Petroleum Processing and Light Hydrocarbon ConversionCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

Single-atom catalysts(SACs)are considered the best candidates for olefin hydroformylation due to their combined advantages of homogeneous and heterogeneous *** conventional organo-phosphine modification,Rh SAC is modified by introducing Ca,resulting in a significant increase in activity(maximum~5.7-fold)and ***,a volcano curve between Ca addition ratio and catalytic activity is *** Ca significantly increases activity by decreasing the energy barrier,but excessive Ca decreases activity due to hindering substrate adsorption and reaction.

关键词： hydroformylation bimetallic single-atom catalysts rhodium heterogeneous catalyst

organo-electroreduction enables arylcarboxylation of styrenes

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Science China chemistry 2024年第11期 3825-3832页

作者： Yanwei Wang Qian Wang Zile Zhu Weikang Qi Youai Qiu State key laboratory and Institute of Elemento-Organic chemistry Frontiers Science Center for New Organic Matter Haihe Laboratory of Sustainable Chemical Transformations College of Chemistry Nankai University

Electroreduction offers an alternative to generate high active intermediates from electrophiles(halides, alkenes, etc.) in organic synthesis. However, it still remains challenge to enable the transformations in controlled fashion for substrates with similar reduction potentials. Herein, an electroreductive arylcarboxylation of styrenes with aryl halides and CO2promoted by an organomediator has been developed. The reaction exhibits the remarkable reactivity control between styrenes and aryl halides bearing very similar reduction potentials, which is enabled by the addition of a simple organic mediator. The mediated process for different kinds of aryl halides(iodides and bromides) could be achieved by simply tuning the electronic effect of the skeleton of naphthalene. This protocol displays a broad substrate scope and the extension to late-stage modification of biorelevant molecules and their derivatives showed a bright prospect. Moreover, density functional theory(DFT) calculations and mechanistic studies have been conducted and provide solid support to rationalize the selectivity and reactivity control observed.

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Designing highly transparent cerium doped Y_(2)O_(3) ceramics with high mechanical and thermal properties for UV-shielding in extreme conditions

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Journal of Advanced Ceramics 2024年第7期13卷 1032-1042页

作者： Cong Zhang Jianqi Qi Xiaolan Zhou Zhonghua Lu Tiecheng Lu College of Physics Sichuan UniversityChengdu 610064China key laboratory of High Energy Density Physics of Ministry of Education Sichuan UniversityChengdu 610064China key laboratory of Radiation Physics and Technology of the Ministry of Education Sichuan UniversityChengdu 610064China

Ultraviolet(UV)radiation poses risks to both human health and *** response to the urgent demand for UV-shielding across various applications,extensive endeavors have been dedicated to developing UV-shielding materials spanning from wide-bandgap semiconductors to organo-inorganic composite ***,existing UV shielding materials,though suitable for daily use,cannot meet the demands of extreme *** this work,we incorporated CeO_(2)as a UV absorber into Y_(2)O_(3)transparent ceramics for *** effect of CeO_(2)concentration on the optical,mechanical,and thermal properties of Y_(2)O_(3)ceramics was systematically *** findings indicate that CeO_(2)serves not only as a UV absorber but also as an effective sintering aid for Y_(2)O_(3)transparent *** 5 at%Ce-doped Y_(2)O_(3)transparent ceramics exhibit the optimal optical quality,with in-line transmittance of~77%at 800 *** introduction of Ce shifted the UV cutoff edge of Y_(2)O_(3)transparent ceramics from 250 to 375 nm,which was attributed to the visible band absorption of Ce^(4+).This shift grants UV shielding capabilities to Y_(2)O_(3)transparent ceramics,resulting in 100%shielding for ultraviolet C(UVC,100-280 nm)and ultraviolet B(UVB,280-320 nm)and~95%shielding for ultraviolet A(UVA,320-400 nm).The service stability(optical properties)under various corrosive conditions(acid,alkali,UV irradiation,and high temperature)was investigated,confirming the excellent stability of this transparent ceramic UV-shielding material.A comparison of the performance parameters of transparent ceramics with those of traditional UV shielding materials such as glasses,films,and coatings was *** work provides innovative design concepts and an effective solution for UVshielding materials for extreme conditions.

关键词： ultraviolet(UV)-shielding transparent ceramics bandgap engineering thermal properties optical properties

Design, synthesis and herbicidal activities of novel self-dispreading phenoxy carboxylic acid derivatives for the control of water hyacinth floating on the water surface

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Chinese Chemical Letters 2015年第8期26卷 1008-1010页

作者： Lv-Yin Zheng Ren-Miao Wu Wei Guo Wen-Hua You Yan-Lan Ling Xiao-Lin Fan key laboratory of organo-pharmaceutical chemistry of Jiangxi Province Gannan Normal University

A series of novel self-dispreading phenoxy carboxylic acid derivatives were designed and synthesized by I2 catalyzed one-step reaction. Their structures were confirmed by IR, NMR, and HRMS. The derivatives can self-spread and float on the water surface. Preliminary bioassays showed that some compounds, 3i–3p, had excellent herbicidal activities against water hyacinth. This strategy provided a novel approach for the water hyacinth control.

关键词： phenoxy carboxylic floating catalyzed spread afford facile benzene acetic tetra

organocatalytic difluorobenzylation of 1,2-diketones via mild cleavage of carbon-carbon bonds

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Organic chemistry Frontiers 2022年第3期9卷 745-751页

作者： Yong Zhang Guo-Wei Lai Long-Jun Nie Qifang He Mei-Juan Lin Rong Chi Dong-Liang Lu Xiaolin Fan key laboratory of organo-pharmaceutical chemistry Gannan Normal UniversityGanzhou 341000P.R.China

α-Aryl-α,α-difluoroacetophenones(DFAPs)are developed as a new class of difluorobenzylation reagents that can be facilely prepared from readily available and cheap starting *** situ carbon-carbon bond cleavage of electron-deficient DFAPs gives difluorobenzyl carbanions that undergo base-catalyzed nucleophilic addition to isatins.

关键词： materials benzyl cleavage