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Nano Research 2017年第9期10卷 2954-2965页

作者： Bolun Wang Guodong Wen Dangsheng SU Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Inorganic Chemistry Fritz Haber Institute of the Max Planck Society Berlin 14195 Germany

The acid-catalyzed ring-opening reaction of styrene oxide was used as a probe reaction for evaluating the acidic properties of carboxylated carbocatalysts. Significant discrepancies in the initial reaction rates were normalized using the total number of carboxyl groups, and demonstrated that the average catalytic activities of the carboxyl moieties on the carbocatalysts differed. Comparisons between the apparent activation energy E a and the pre-exponential factor A, derived from Arrhenius analysis, demonstrated that A varied more significantly, and therefore had a more significant effect on the reaction rates than E a. The variation in the calculated pKa values of the carboxyl groups was attributed to the electronic effects of the nitro groups. This hypothesis was supported by the temperature programmed desorption profiles of nitrogen monoxide ions.

关键词： carboxylated carbocatalysts acidic properties ring-opening reaction Arrhenius analysis pKa values electronic effect

Syntheses of 2- or 6-Substituted Chromones and Chromone ring-opening reaction in Polyphosphoric Acid

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Chemical Research in Chinese Universities 2004年第3期20卷 299-304页

作者： HE Xun-gui YOU Qi-dong LI Zhi-yu Department of Medicinal Chemistry School of PharmacyChina Pharmaceutical UniversityNanjing 210009P.R.China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203P.R.China

In an attempt to find new antitumor agents,a novel class of chromone compounds with a benzimidazole or a benzoxazole ring in positions 2 or 6 were synthesized via condensation in polyphosphoric acid(PPA) by using chromone acids as the starting materials. During the preparation process,it was found that PPA could cleave the chromone ring to produce a ring-opening compound(6). The molar ratio of the chromone compound(5) to the ring-opening compound(6) varied with the change of reaction temperature and time. Based on MTT protocol,the antitumor activity of each of the compounds obtained was evaluated against three human cancer cell lines: KB(oral epidermal),A2780(ovary) and Bel7402(liver). The IC_ 50 varied from 54.7 μmol/L to more than 180 μmol/L.

关键词： 2-or 6-Substituted chromone Antitumor agent Polyphosphoric acid ring-opening reaction

Platinum-Catalyzed Asymmetric ring-opening reaction of Oxabenzonorbornadiene with Terminal Alkynes

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Chinese Journal of Chemistry 2014年第7期32卷 613-618页

作者： Yuhua Long Han Jiang Zhifu Zou Kaixuan Chen Yali Fang School of Chemistry and Environment South China Normal UniversityGuangzhouGuangdong 510006China

A novel platinum-catalyzed asymmetric ring-opening reaction of oxabenzonorbornadiene with terminal alkynes is *** reaction affords optically active cis-2-alkynyl-1,2-dihydronaphthalen-1-ols in moderate yields with good enantioselectivity in the presence of catalytic amounts of Pt(COD)Cl_(2)/(S)-BINAP and an excess of zinc *** products were obtained exclusively with the relative cis-configuration of the ring substituents and the prevalent(1R,2S)-configuration of the stereocenters,as determined by single crystal X-ray diffraction analysis.

关键词： platinum-catalyzed asymmetric catalysis ring-opening reaction oxabenzonorbornadiene terminal alkyne

Synthesis of Chiral Acyclic Nucleoside Analogues via the ring-opening reaction of Chiral Epoxides

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Synthesis of Chiral Acyclic Nucleoside Analogues via the Rin...

Pyridine-N-oxide： An Efficient Organocatalyst for ring- opening reactions of Aziridines with Aryl Thiols

河南省化学会2016年学术年会

作者： Tao Wei Ming-Sheng Xie Dong-Chao Wang Gui-Rong Qu Hai-Ming Guo Key Laboratory of Green Chemical Media and reactions Ministry of Education School of Chemistry and Chemical Engineering Henan Normal University

Many chiral acyclic nucleoside analogues exhibit outstanding anti-virus and anti-cancer activities. Thus, developing efficient synthesis methods to construct chiral acyclic nucleoside analogues have attracted more and more attention. In the context of our ongoing projects in selectively modifying nucleosides, herein, we developed an efficient route for the synthesis of chiral acyclic nucleoside analogues via the ring-opening reaction of chiral epoxides and nucleobase(Scheme 1). This method suggests an opportunity to acquire many other useful chiral acyclic nucleoside analogues.

关键词： Chiral acyclic Nucleoside Analogues ring-opening reaction

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Chinese Journal of Chemistry 2011年第1期29卷 79-84页

作者： Yang, Qin Yin, Zhenlan Yang, Min Peng, Yiyuan Jiangxi Key Laboratory of Green Chemistry Department of Chemistry Jiangxi Normal University Nanchang Jiangxi 330027 China Key Laboratory of Functional Small Organic Molecule Ministry of Education College of Life Science Jiangxi Normal University Nanchang Jiangxi 330022 China

Pyridine-N-oxide serves as an efficient catalyst for the ring-opening reactions of N-tosylaziridines with various aryl thiols under mild conditions. This transformation is highly effective, which gives rise to the cor... 详细信息

关键词： pyridine-N-oxide ring-opening reaction N-tosylaziridine thiol β-amino sulfide

Cationic Micelle-catalyzed ring-opening reactions of Aziridines with Thiols in Water

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Chinese Journal of Chemistry 2011年第3期29卷 499-503页

作者： Yang, Min Yang, Qin Chen, Puqing Peng, Yiyuan Key Laboratory of Functional Small Organic Molecule Ministry of Education and College of Chemistry and Chemical Engineering Nanchang Jiangxi 330022 China Jiangxi Key Laboratory of Green Chemistry and College of Life Science Jiangxi Normal University Nanchang Jiangxi 330022 China

An efficient and practical method is described for the ring-opening reactions of N-tosylaziridines with various thiols in water under mild conditions. Various surfactants have been evaluated to optimize the reactions. Under optimal conditions, these reactions gave rise to the corresponding β-amino sulfides in good to excellent yields.

关键词： pyridine-N-oxide ring-opening reaction N-tosylaziridine thiol β-amino sulfide

Uniform Metal Sulfide@N-doped Carbon Nanospheres for Sodium Storage: Universal Synthesis Strategy and Superior Performance

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Energy & Environmental Materials 2023年第2期6卷 389-396页

作者： Kai Yang Hao Fu Yixue Duan Manxiang Wang Minh Xuan Tran Joong Kee Lee Woochul Yang Guicheng Liu Department of Physics Dongguk UniversitySeoul 04620Korea Shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and TechnologyXi’an 710021China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China College of Physics and Electronic Information Yan’an UniversityYan’an 716000China Center for Energy Storage Research Clean Energy InstituteKorea Institute of Science and Technology(KIST)Seoul 02792Korea

Nitrogen-doped carbon-coated transition-metal sulfides(TMS@NCs)have been considered as efficient anodes for sodium-ion ***,the uncontrollable morphology and weak core-shell binding forces significantly limit the sodium storage performance and ***,based on the reversible ring-opening reaction of the epoxy group of the tertiary amino group-rich epoxide cationic polyacrylamide(ECP)at the beginning of hydrothermal process(acidic environment)and the irreversible ring-opening(cross-linking reactions)at the late hydrothermal period(alkaline environment),47 nm-sized ZnS@NCs were prepared via a one-pot hydrothermal *** this process,the covalent bonds formed between the ZnS core and elastic carbon shell significantly improved the mechanical and chemical stabilities of ZnS@*** from the nanosize,fast ion/electron transfer,and high stability,ZnS@NC exhibited a high reversible capacity of 421.9 mAh g^(−1) at a current density of 0.1 A g^(−1) after 1000 cycles and a superior rate capability of 273.8 mAh g^(−1) at a current density of 5 A g^(−1).Moreover,via this universal synthesis strategy,a series of TMS@NCs,such as MoS_(2)@NC,NiS@NC,and CuS@NC were developed with excellent capacity and cyclability.

关键词： anode materials core-shell structure nitrogen-doped carbon ring-opening reaction transition-metal sulfide

Preparation of Optically Active 2,2'-Dibromo-6,6'-diiodo-1,1'-biphenyl:A Powerful Precursor for Modular Synthesis of Functionalized Atropisomers

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Chinese Journal of Chemistry 2023年第24期41卷 3515-3520页

作者： Yuanyuan Li Longhui Duan Biqiong Hong Zhenhua Gu Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China96 Jinzhai RoadHefeiAnhui230026 China College of Materials and Chemical Engineering Minjiang UniversityFuzhouFujian350108 China

The widespread applications of atropisomeric compounds have led to an increasing demand for their *** than synthesizing different functionalized atropisomers individually,an attractive alternative is to identify a key intermediate or precursor that can be readily elaborated and functionalized to realize divergent synthesis of this class of *** on our previous research on asymmetric ring-opening of cyclic diaryliodoniums,in this work we developed a copper-catalyzed enantioselective ring-opening reaction of ortho,ortho’-dibromo substituted cyclic diaryliodonium with lithium *** resulting optically active product 2,2'-dibromo-6,6'-diiodo-1,1'-biphenyl,possessing two C—Br bonds and two C—I bonds,can be selectively advanced to form different ***,the utilities of the product were highlighted by successively demonstrating C—I and C—Br metalation,followed by carboxylation,boroylation,oxygenation,allylation,phosphinylation,etc.,all of which provide a new and convenient approach to synthesizing a range of functionalized axially chiral biphenyls.

关键词： Atropisomerism Asymmetric catalysis ring-opening reaction Chirality Copper

Transition-Metal-Catalyzed Carbon-Carbon Bond Activation in Asymmetric Synthesis

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Chinese Journal of Chemistry 2021年第5期39卷 1397-1412页

作者： Xiufen Bi Qiuchi Zhang Zhenhua Gu Ocean College Minjiong University FuzhouFujian350108China Hefei National Laboratory for Physical Science at the Microscale and Department of ChemistryCenter for Excellence in Molecular SynthesisUniversity of Science and Technology of China96 Jinzhai RoadHefeiAnhui 230026China

Catalytic asymmetric transformations involving carbon-carbon bond cleavages open intriguing strategies for the synthesis of chiral complex *** transient organometallic species mainly generate from the oxidative addition of cyclic compounds with low valence metals or from β-carbon elimination of tert-alkoxyl *** overview covers the recent advances in transition-metal-catalyzed carbon-carbon bond activation in asymmet-ric synthesis.

关键词： Carbon-carbon activation Transition-metal Asymmetric catalysis Asymmetric synthesis ring-opening reaction

SYNTHESIS OF 3-BENZYL-GLYCERIC ACID:A KEY INTERMEDIATE OF A NOVEL CYCLIC ESTER MONOMER

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Chinese Journal of Polymer Science 2002年第2期20卷 177-180页

作者：冯新德 Department of Polymer Science and Engineering Peking University Beijing 100871 China

A route was proposed to synthesize 3-benzyl-glyceric acid (3-BGA) as an important intermediate for the synthesis of a novel six-membered cyclic ester monomer-3-benzyloxymethyl-1,4-dioxane-2,5-dione (3-BMG). According to this route, 3-BGA was obtained from ring-opening reaction of benzyl alcohol with methyl glycidate, which was prepared from the epoxidation of methyl acrylate using sodium hypochlorite as the oxidant.

关键词： 3-benzyl-glyceric acid epoxidation benzyl alcohol ring-opening reaction