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visible light-promoted, iodine-catalyzed selenoalkoxylation of olefins with diselenides and alcohols in the presence of hydrogen peroxide/air oxidant: an efficient access to α-alkoxyl selenides

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Science China Chemistry 2018年第3期61卷 294-299页

作者： Mingxuan Liu Yiming Li Lei Yu Qing Xu Xuefeng Jiang Institute of Pesticide School of Chemistry and Chemical Engineering and School of Horticulture and Plant Protection Yangzhou University Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University

Under iodine-catalyzed and visible light-irradiated aerobic conditions, selenoalkoxylation of olefins with diselenides and alcohols can be efficiently achieved to afford the useful α-alkoxyl selenides in the presence of only 0.5 equiv. of H_2O_2. Controlling the sub-stoichiometric H_2O_2 amount is crucial to avoid the non-selective over-oxidation of the diselenides that leads to the ineffective hyper-valent selenium compounds. Meanwhile, under visible light irradiation, the green, safe, and low-cost air can work as a supplemental mild oxidant in the reaction to ensure selective oxidation of the diselenides, full conversion of the reactants, and ultimately good yield of the products.

关键词： selenium alkoxyl selenide aerobic oxidation visible light iodine catalysis

visible light induced photodegradation of organic pollutants on nitrogen and fluorine co-doped TiO_2 photocatalyst

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Journal of Environmental Sciences 2005年第1期17卷 76-80页

作者： WANGZheng-peng XUJun CAIWei-min ZHOUBao-xue HEZheng-guang CAIChun-guang HONGXiao-ting SchoolofEnvironmentalScienceandEngineering ShanghaiJiaotongUniversityShanghai200240China

The nitrogen and fluorine co doped TiO 2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetra butyl titanate with ammonium fluoride. Nitrogen and fluorine co doping causes the absorption edge of TiO 2 to shift to a lower energy region. The photocatalytic activity of co doped TiO 2 with anatase phases was found to be 2 4 times higher than that of the commercial TiO 2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation. The co doped TiO 2 powders only contain anatase phases even at 1000℃. Apparently, ammonium fluoride added retarded phase transformation of the TiO 2 powders from anatase to rutile. The substitutional fluorine and interstitial nitrogen atoms in co doped TiO 2 polycrystalline powder were responsible for the vis light response and caused the absorption edge of TiO 2 to shift to a lower energy region.

关键词： photocatalyst visible light nitrogen and fluorine co-doped phenol band gap

visible light catalyzed aromatization of 1,3,5-triaryl-2-pyrazolines by platinum(Ⅱ) polypyridyl complex under oxidant-free condition

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Science China Chemistry 2016年第2期59卷 175-179页

作者： Pan Ye Deng-Hui Wang Bin Chen Qing-Yuan Meng Chen-Ho Tung Li-Zhu Wu School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing 100190 China

With visible light(λ=450 nm) irradiation of a catalytic amount of platinum(Ⅱ) terpyridyl complex, 1,3,5-triaryl-2-pyrazolines can be smoothly converted to their corresponding pyrazoles and hydrogen in quantitative y... 详细信息

关键词： pyrazolines pyrazoles photoredox catalysis visible light platinum(Ⅱ) terpyridyl complex

visible light Photocatalytic Properties of Metastable γ-Bi_2O_3 with Different Morphologies

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Journal of Materials Science & Technology 2014年第2期30卷 192-196页

作者： Weichang Hao Yuan Gao Xi Jing Wen Zou Yan Chen Tianmin Wang Center of Materials Physics and Chemistry Beihang University Institute for Superconducting and Electronic Materials University of Wollongong

The metastable γ-Bi2O3 photocatalysts with different morphologies were fabricated by means of a chemical precipitation method. The microstructure of as-prepared samples was characterized by X-ray diffraction, transmission electron microscopy and ultraviolet-visible diffusion reflectance spectroscopy. The photocatalytic performance of Bi2O3 powder was evaluated using rhodamine B as a model pollutant under visible light irradiation. The visible light photocatalytic activity of Bi2O3 with different morphologies is as follows, nanorod 〉 nanorod/nanoflake 〉 N doped TiO2 〉 irregular particle 〉 agglomerated particle. The γ-Bi2O3 shows the best photocatalytic performance and it can effectively degrade 97% RhB within 60 min.

关键词： γ-Bi2O3 visible light Photocatalytic properties Morphology

visible light-Induced Photocatalysis on Carbon Nitride Deposited Titanium Dioxide： Hydrogen Production from Sacrificial Aqueous Solutions

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Chinese Journal of Chemistry 2017年第2期35卷 165-172页

作者： Shinya Higashimoto Kohji Hikita Masashi Azuma Mari Yamamoto Masanari Takahashi Yoshihisa sakata Masaya Matsuoka Hisayoshi Kobayashi Department of Applied Chemistry College of Engineering Osaka Institute of Technology 5-16-10miya Asahi-ku Osaka 535-8585 Japan Osaka Municipal Technical Research Institute 1-6-50 Morinomiya Joto-ku Osaka 536-8553 Japan Graduate School of Science andEngineering Yamaguchi University 2-16-1 Tokiwadai Ube 755-8611 Japan Department of Applied Chemistry Graduate School of Engineering Osaka Prefecture University 1-1 Gakuen-cho Naka-ku Sakai Osaka 599-8531 Japan Department of Chemistry and Materials Technology Kyoto Institute of Technology Matsugasaki Sakyo-ku Kyoto 606-8585 Japan

Carbon and nitrogen species-involved TiO2 （CN-TiO2） were systematically synthesized by thermal condensa- tion of cyanuric acid on the TiO2 surface. And the photocatalytic reactions for H2 production from sacrificial aque- ous solutions were performed on several CN-TiO2 photocatalyst under visible-light irradiation. The photocatalytic activity of the CN-TiO2 was influenced by total amounts of carbon and nitrogen species, and the preferable activity was ten times higher than that of pristine carbon nitride. Here, the states of the CN-TiO2 photocatalyst were charac- terized by XPS, FT-IR and UV-Vis spectroscopy as well as DFT calculations. The photo-electrochemical measure- ments confirmed that the enhancement of H2 production is associated with effective charge separation under photo- excitation of highly dispersed carbon nitride on the TiO2 surface.

关键词： carbon nitride TiO2 visible light photo-electrochemistry DFT calculation sacrificial H2 production

Preparation,Characterization and visible light Photocatalytic Activity of Nitrogen-doped TiO_2

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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 71-77页

作者：王正鹏 School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The N-doped TiO2 polycrystalline powder was synthesized through calcining the hydrolysis prodact of tetra-butyl titanate with ammonia. The photocatalytic activity of N-doped TiO2 powder with anatase phone calcined at 400℃ was 2.7 times higher than that of Degussa P25 for phenol decomposition under visible light. All samples had mesoporoas structures. X- ray photoelectron spectroscopy confirmed that a trace amount of N atoms remained in the anatase polycrystaUine TiO2 powder when calcined at 400 ℃ as substitutional atoms at the oxygen sites. UV-Vis and EPR analyses indicated that oxygen vacancy states were created during the course of N-doped TiO2 powder formation. It is considered that substitutional N atoms, oxygen vacancy, states, large BET surface areas and mesoporoas structure are important facwrs for the N-doped photocatalyst to present a high vis-activity.

关键词： photocatalyst visible light nitrogen-doped TiO2 phenol

visible light Accelerated Vinyl C-H Arylation in Pd-Catalysis：＂ Application in the Synthesis of ortho Tetra-substituted Vinylarene Atropisomers

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Chinese Journal of Chemistry 2018年第1期36卷 11-14页

作者： Jia Feng Bin Li Julong Jiang Mingkai Zhang Wenbai Ouyang Chunyu Li Yao Fu Zhenhua Gu Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China 96 Jinzhai Road Hefei Anhui 230026 China

A visible light accelerated C-H functionalization reaction in palladium-catalyzed arylation of vinyl arenes with diaryliodonium salts is reported in the absence of additional photosensitizer. The kinetic isotope effect （kH/kD） was changed from 3.6 （under darkness） to 1.1 when irradiated by visible light, which indicated that the C-H functionalization step was the rate determining step under darkness and significantly accelerated by the irradia- tion of visible light. Finally the synthesis of ortho tetra-substituted vinylarene atropisomers with high enantiospecificity was realized via this protocol.

关键词： palladium visible light C-H functionalization isotope effect atropisomer

visible light-curable polymers for biomedical applications

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Science China Chemistry 2014年第4期57卷 510-521页

作者： ZHOU Di ITO Yoshihiro Emergent Bioengineering Materials Research Team RIKEN Center for Emergent Matter Science Jiangsu Key Laboratory of Advanced Functional Materials School of Chemistry and Material EngineeringChangshu Institute of Technology

Photocurable systems, which offer advantages such as microfabrication and in situ fabrication, have been widely used as dental restorative materials. Because the visible light-curable(VLC) system causes no biological damage, it is popular as a dental material and is being investigated by many researchers for other medical applications. Here, the principle of the VLC system is explained and recent progress in key components including photoinitiators, monomers, macromers, and prepolymers is discussed. Finally, biomedical applications for drug delivery and soft tissue engineering are reviewed. Considering the recent development of VLC systems, its importance in the field of medical applications is expected to continue to increase in the future.

关键词： visible light photocuring photoinitiator polymer biomedicine

visible light-Promoted Sulfoxonium Ylides Synthesis from Aryl Diazoacetates and Sulfoxides

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Chinese Journal of Chemistry 2021年第6期39卷 1646-1650页

作者： Juan Lu Lei Li Xiang-Kui He Guo-Yong Xu Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefeiAnhui 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University) Ministry of EducationHefeiAnhui 230601 China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province School of ScienceWestlake University18 Shilongshan RoadHangzhouZhejiang 310024China Institute of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China

A visible light-promoted reaction of donor/acceptor diazoalkanes with sulfoxides towards the synthesis of synthetically useful sulfoxonium ylides was *** reaction occurred under sole visible light irradiation without the need of any transition-metals or additives,affording the corresponding sulfoxonium ylides in moderate to good *** success of late-stage modification of natural isolates or drug candidates,scale-up reaction and transformation of sulfoxonium ylides to other useful molecules further rendered the approach valuable.

关键词： Sulfoxonium ylides Synthetic methods Carbene visible light Diazo compounds