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catalyst-free multicomponent polymerization of sulfonyl azide,aldehyde and cyclic amino acids toward zwitterionic and amphiphilic poly(N-sulfonyl amidine)as nanocatalyst precursor

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Science China Chemistry 2022年第9期65卷 1798-1806页

作者： Erli Tian Ming Li Wangze Song Nan Zheng State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China

Polymers with metal coordination ability are outstanding precursors of nanocatalysts,attracting numerous attention in nanocatalysis area.It has been rarely reported for the poly(N-sulfonyl amidines)as macromolecular ligands for nanocatalysis.Herein,a catalyst-free multicomponent polymerization(MCP)strategy is developed to facilely prepare a library of amphiphilic poly(Nsulfonyl amidines)with zwitterionic properties starting from disulfonyl azide,hydrophilic dialdehyde and cyclic amino acids including proline and pipecolinic acid.Metals or additives can be thorougly avoided through this method.All the obtained polymers have well-defined structures,high yields and weight-average molecular weights(M_(w)s,up to 99,300 g/mol).The unique zwitterionic property,amphiphilicity and Cu(Ⅰ)coordination ability of the obtained poly(N-sulfonyl amidines)endow them to form the polymer-Cu(Ⅰ)complexes as nanocatalysts.Such nanocatalysts exhibit high catalytic efficiency in aqueous Cucatalyzed azide-alkyne cycloaddition(CuAAC)reaction at a low Cu(Ⅰ)loading of 50 ppm.Nanocatalysts with a high ratio of polymers to Cu(Ⅰ)have also been demonstrated with Cu(Ⅰ)stabilization ability.This work provides a“green”MCP method toward zwitterionic and amphiphilic poly(N-sulfonyl amidines),and highlights their unique potentials for nanocatalysis.

关键词： multicomponent polymerization zwitterion catalyst-free nanocatalysis poly(N-sulfonyl amidines)

catalyst-free Regio-and Diastereoselective Synthesis of Heterocyclic Nucleosides in the Eco-friendly Solvent 2-Methyltetrahydrofurant

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Chinese Journal of Chemistry 2023年第2期41卷 167-172页

作者： Xiaodong Gu Qingwei Du Weijian Song Jun(Joelle)Wang Department of Chemistry Hong Kong Baptist UniversityKowloonHong KongChina Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China

An efficient and practical synthesis of heterocyclic nucleosides is developed by a catalyst-free highly regioselective and diastereose-lective[3+2]annulation of a-purine-substituted acrylates with nitrones.The reaction operates with excellent functional group toler-ance,very mild reaction conditions,and with the green,sustainable,and eco-friendly 2-methyltetrahydrofuran(2-MeTHF)as sol-vent.Compared with other reactions of electron-deficient olefin dipolarophiles with nitrones,different regioselective cycloaddition products were observed in this work.This 1,3-dipolar cycloaddition reaction gives a series of isoxazolidinyl nucleosides in good to excellent yields with promising applications in biochemistry and medicinal chemistry.

关键词： Heterocycle Nucleoside catalyst-free Annulation Regioselectivity Synthetic methods Cycloaddition

Chemo-, site-selective reduction of nitroarenes under blue-light, catalyst-free conditions

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Chinese Chemical Letters 2022年第5期33卷 2420-2424页

作者： Bin Wang Jiawei Ma Hongyuan Ren Shuo Lu Jingkai Xu Yong Liang Changsheng Lu Hong Yan State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

The tandem reaction of photoinduced double hydrogen-atom transfer and deoxygenative transborylation for chemo-and site-selective reduction of nitroarenes into aryl amines under catalyst-free, room temperature conditions was disclosed in excellent yields. In this reaction, isopropanol(^(i)PrOH) was used as hydrogen donor and tetrahydroxydiboron [B_(2)(OH)_(4)] as deoxygenative reagent with green, cheap, and commercially available credentials. In particular, a wide range of reducible functional groups such as halogen(-Cl,-Br and even-I), alkenyl, alkynyl, aldehyde, ketone, carboxyl, and cyano are all tolerated. Moreover,the reaction preferentially reduces the nitro group at the electron-deficient site over another nitro group in the same molecule. A detailed mechanistic investigation in combination of experiments and theoretical calculations gave a reasonable explanation for the reaction pathway.

关键词： Nitroarenes Selective Reduction catalyst-free Photoinduced Transborylation

Rosin side chain type catalyst-free vitrimers with high cross-link density,mechanical strength,and thermal stability

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化学科学与工程前沿:英文版 2023年第9期17卷 1267-1279页

作者： Yunpeng Shen Weishan Tang Jinyang Li Zhijun Ke Lirong Liao Peng Yang Yuntao Lu Xiaoping Rao College of Chemical Engineering Huaqiao UniversityXiamen361021China Academy of Advanced Carbon Conversion Technology Huaqiao UniversityXiamen361021China

The emergence of vitrimer,a new class of polymer materials can address the problem of recyclability,reprocess ability and recyclability of thermosetting plastics.Rosin,a natural product,is an ideal raw material for the preparation of polymers in a more sustainable way.Nevertheless,due to the huge steric hindrance caused by the hydrogenated phenanthrene ring structure,the cross-link density of materials is frequently lowered.In this study,hydrogenated rosin was adopted for preparing hydrogenated rosin side-chain type diacids,which were reacted with mixed epoxy to obtain rosin side-chain type vitrimers.It was completely characterized by differential scanning calorimetry test,thermogravimetric analysis,shape memory test and self-healing test.The prepared vitrimers exhibited good self-healing properties,excellent heat resistance(T_(d)=352℃)as well as high mechanical properties(tensile strength of 46.75 MPa).The tricyclic diterpene structure of rosin was introduced into the side chain in order to avoid the reduction of cross-link density resulting from the huge steric hindrance of the rigid tricyclic hydrophenylene skeleton.Vitrimers can undergo dynamic transesterification reaction without external catalysts due to the autocatalytic effect of tertiary amines from epoxy.Moreover,our work expanded the application field of rosin,increased the added value of rosin,and provided a novel method for preparing rosin-based vitrimers with ideal properties.

关键词： vitrimers rosin catalyst-free high mechanical properties dynamic transesterification reaction

catalyst-free Photochemical Bromination of Unprotected Aromatic Amino Acid Derivatives by Using a Rotating Ultraviolet Photoreactor

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Chemical Research in Chinese Universities 2022年第2期38卷 505-509页

作者： ZHANG Tingting LUO Pan LAI Can LIU Zheyi JIN Yan WANG Fangjun CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Aromatic amino acid halides are valuable amino acid derivatives and fundamental building blocks that are used to various coupling reaction^1-3!,such as Heck,Suzuki and Ullmann reaction[4-7],and also important precurso... 详细信息

关键词： catalyst-free Photochemistry Bromination 254 nm UV Unprotected aromatic amino acid derivative

Base-Promoted catalyst-free Regioselective Hydroacylation of Styrenes with Hydrazones via Carbanion Addition

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CCS Chemistry 2022年第10期4卷 3254-3263页

作者： Pan Pan Yatao Lang Dawei Cao Huiying Zeng Chao-Jun Li The State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000 Gansu FRQNT Center for Green Chemistry and Catalysis McGill UniversityMontrealQuebec H3A 0B8

Wereport a base-promoted catalyst-free protocol for the highly regioselective hydroacylation of styrenes with hydrazones derived from naturally abundant aldehydes.This protocolgeneratedlinearketoneswith goodfunctional grouptolerance anda broadsubstrate scope under mild conditions.Mechanistic studies showed that the addition of hydrazone anion to a styrene double bond was the key step,different from previoushydroacylationpathways(viaorganometallic complexes or radical intermediates).

关键词： catalyst-free regioselective hydroacylation hydrazone carbanion addition base-promoted

catalyst-free and atom-economical 1,3-dipolar cycloaddition of C,N-cyclic azomethine imines:Facile synthesis of isoquinoline-fused spirocycles

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Green Synthesis and Catalysis

Green Synthesis and Catalysis 2022年第1期3卷 69-78页

作者： Lesong Li Tao Liu Xiaoli Zhang Xiaohan Hou Hao Dong Xiaoyang Li Weiwu Ren Yang Wang Molecular Synthesis Center&Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and Technology(QNLM)Qingdao 266237China

A highly efficient and environmentally benign 1,3-dipolar cycloaddition of C,N-cyclic azomethine imines with 5-alkenyl thiazolones and 2-arylidenindane-1,3-diones is developed for the construction of congested quaternary spiro-carbon centers.All these transformations can be smoothly performed in ethanol at room temperature,providing a catalyst-free and atom-economical access to diversely substituted novel isoquinoline-fused spirocycles in almost quantitative yields with high diastereoselectivities.The promising anti-tumor activity of these structurally novel spirocyclic compounds is reported as well.

关键词： catalyst-free Atom-economical 1,3-Dipolar cycloaddition C,N-cyclic azomethine imine 5-Alkenyl thiazolone 2-Arylidenindane-1,3-dione

catalyst-free Hydroxytrifluoromethylation of Alkenes UsingIodotrifluoromethane

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Chinese Journal of Chemistry 2019年第1期37卷 597-604页

作者： Zhaoben Su Yong Guo Qing-Yun Chen Zhi-Gang Zhao Bao-Yi Nian College of Chemistry & Environment Protection Engineering Southwest Minzu UniversityChengduSichuan 610041China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciencesand University of Chinese Academy of Sciences345 Lingling RoadShanghai 200032China Sanming Institute of Fluorochemical Industry Sanming UniversitySanmingFujian 365004China

The importance of CF3-containing molecules in pharmaceuticals, agrochemicals and materials intrigues the intense interest in synthetic methodology of these compounds. With a purpose to enrich trifluoromethylation methodology, we carefully examined the substrate scope of hydroxytrifluoromethylation of alkenes using iodotrifluoromethane, and the reaction provided β-trifluoromethyl alcohols in good yields under extremely mild conditions without catalysts. We found that our reaction can be applied to not only styrenes but also various aliphatic alkenes with excellent selectivity;no ketone was detected in most of our cases. Another feature of our discovery is “simple”. The reaction was carried out in air, irradiated by visible light, at room temperature and most importantly no catalyst was needed. A solution of CF3I in DMSO was used as the facile trifluoromethylating reagent, which simplified the utilization of gaseous CF3I. Based on 19F NMR spectroscopy, we observed a halogen bond between CF3I and tertiary amine in this reaction. The interaction may promote single electron transfer by the visible light irradiation.

关键词： trifluoromethyl catalyst-free hydroxylation alkenes photochemistry

catalyst-free Reaction in Water: Synthesis of Functionalized Tetrahydroindole Derivatives via Three-Component Domino Reaction

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Chinese Journal of Chemistry 2014年第9期32卷 889-896页

作者： Xian Feng Jianjun Wang Wei Lin Juanjuan Zhang Zhibin Huang Daqing Shi Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China

An environmentally benign and efficient method has been developed for the synthesis of functionalized tetrahydroindole derivatives in aqueous media under catalyst-free conditions,by simply combining a phenylglyoxal monohydrate,an enaminone,and a barbituric acid.The advantages of this method are that it is catalyst free,has an easy workup,provides good yields,and uses water as solvent,which make this procedure facile and practical.

关键词： functionalized tetrahydroindole derivatives multi-component reaction catalyst-free aqueous medium green chemistry