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Asymmetric catalytic 1,3-dipolar cycloaddition ofα-diazoesters for synthesis of 1-pyrazoline-based spirochromanones and beyond

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Science China Chemistry 2021年第8期64卷 1355-1360页

作者： Peng Zhao Zegong Li Jun He Xiaohua Liu Xiaoming Feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly enantioselective 1,3-dipolar cycloaddition ofα-substituted diazoesters with exocyclic enones was achieved with chiral scandium(III)/N,N’-dioxide complex as the catalyst.This protocol provided a facile and efficient route to optically active 1-pyrazoline-based spirochromanones and others with good outcomes(up to 97%yield,98%ee with>95:5 dr).Moreover,enantioenriched 2-pyrazoline-based spirochromanones were also accessible by switchingα-substituted diazoesters toα-diazoacetates.The further specific transformations of chiral pyrazoline-based spiro-compounds to spirocyclopropane derivatives were disclosed as well.

关键词： asymmetric synthesis α-diazoesters 1,3-dipolar cycloaddition exocyclic enone pyrazoline

Asymmetric 1,3-dipolar cycloaddition of nitrile oxides with optically active vinylboronic ester

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Chinese Journal of Chemistry 1999年第3期17卷 293-299,203页

作者：姜标张翱阚颖 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Pinanyldioxy styrylboronic ester (1) was employed for asymmetric 1,3-dipolar cycloaddition with nitrile oxides, optically active Δ2-isoxazolines (3) or 4-hydroxy- Δ2-isoxazolines (4) were obtained. The effect of dif... 详细信息

关键词： 1,3-dipolar cycloaddition vinylboronic ester Δ2-isaxazoline 4-hydroxy-Δ2-isoxazoline

Asymmetric 1,3-dipolar cycloaddition of nitrile oxides to chiral acryloyl esters bearing glucofuranose as auxiliary

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Chinese Journal of Chemistry 2000年第2期18卷 220-224页

作者：张翱阚颖姜标 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Asymmetric 1,3-dipolar cycloaddition of nitrite oxides to an acryloyl ester (1) derived from 1, 2:5, 6-di-O-isopropylidene glucose (6) was studied. Solvent and temperature effect was discussed. The single diastereoiso... 详细信息

关键词： 1,3-dipolar cycloaddition 2-isoxazoline acryloyl ester nitrile oxide

1,3-dipolar cycloaddition reaction of two different azomethine ylides to C70

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Chinese Journal of Chemistry 1998年第2期16卷 178-183页

作者：郑大贵李玉良范楼珍李凤英李永舫朱道本 nstitute of Chemistry Chinese Academy of SciencesBeijing 100080ChinaShangrao Teacher's CollegeShangraoJiangzi 334001China nstitute of Chemistry Chinese Academy of SciencesBeijing 100080China

1,3-dipolar cycloaddition to C70 of an azomethine ylide, which was generated in situ from refluxing a mixture of cyclohexanone and DL-valine in chlorobenzene under N2, afforded a monoadduct and a bisadduct. Even for longer reaction time, however, only monoadduct waa obtained from the reaction of C70 with an azomethine ylide generated from refluxing a mixture of 2-undecanone and 2-aminoisobutyric acid in chlorobenzene under N2. The electrochemical properties of all the products were studied by cyclic voltammetry.

关键词： Fullerenes 1,3-dipolar cycloaddition azomethine electrochemical properties

Solvent-free 1,3-dipolar cycloaddition of Azomethine Imines with Terminal Alkynes Promoted by Calcium Fluoride Under the Ball Milling Condition

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Chemical Research in Chinese Universities 2015年第4期31卷 543-548页

作者： CHEN Xianglong JIA Chunman CAO Li ZHANG Dela LIU Shuixiang ZHANG Qil Hainan Provincial Key Lab of Fine Chem. Key Study Center of Ministry of Education for Tropical Resources Utilization Hainan University Haikou 570228 P R. China

A convenient and efficient procedure for the synthesis ofN, N-bicyclic pyrazolidinone derivatives has been developed via the reaction of azomethine imines with terminal alkynes under the ball milling condition without sol- vent, which was promoted by calcium fluoride with a catalyst of copper（I） salt. The cyclization reactions exhibited moderate to high yields.

关键词： Ball-milling 1,3-dipolar cycloaddition Click chemistry Solvent-free reaction

Synthesis of Novel Spiro Thiazolo[3,2-a][1,3,5]triazines via 1,3-dipolar cycloaddition of Azomethine Ylide

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Chinese Journal of Chemistry 2011年第1期29卷 97-101页

作者： Li, Xiaofang Liu, Haochong Zheng, Aiting Li, Zhikui Li, Guobin Yu, Xianyong Yi, Pinggui Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education Hunan Province College Key Laboratory of QSAR/QSPR School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan Hunan 411201 China

The 1,3-dipolar cycloaddition of an azomethine ylide generated by a decarboxylative route from sarcosine and acenaphthenequinone to 7-arylmethylidene-3-aryl-3,4-dihydro-2H-thiazolo[3,2-aJ[1,3,5]triazin-6（7H）-ones afforded novel dispiro[acenaphthylene-1,2’-pyrrolidine]-3＇,7″-[1,3]thiazolo[3,2-a][1,3,5]triazines in moderate yields. The structures of the products were determined and characterized thoroughly by NMR, MS, IR, elemental analysis and X-ray crystallographic analysis. The results of experiment indicated that this 1,3-dipolar cycloaddition proceeded with high stereoselectivity and regioselectivity.

关键词： thiazolo[3,2-a]triazine 1,3-dipolar cycloaddition azomethine ylide spiroheterocycle

Soluble Polymer-Supported Synthesis of Pyrazoles via 1,3-dipolar cycloaddition Strategy

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Chinese Journal of Chemistry 2004年第5期22卷 415-418页

作者：林旭锋王彦广丁寒锋 Department of Chemistry Zhejiang University Hangzhou Zhejiang 310027 China

Rapid parallel liquid-phase synthesis of pyrazoles has first been developed. The 1,3-dipolar cycloaddition be-tween nitrilimines generated in situ and soluble polymer-supported alkynyl or alkenyl dipolarophiles in parallel one-pot fashion gave the corresponding PEG-supported regioisomeric pyrazoles or regiospecific pyrazolines. The latter was assuredly oxidated by DDQ to PEG-supported regiospecific pyrazoles. Cleavage from the support under mild conditions afforded pyrazoles in good yields and high purity.

关键词： pyrazole 1,3-dipolar cycloaddition soluble polymer liquid-phase synthesis combinatorial chemis-try

Preparation of 1,3-Disubstituted-5-cyano-4,5-dihydropyrazoles via 1,3-dipolar cycloaddition of Nitrile Imine with Acrylonitrile

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Chinese Journal of Chemistry 2002年第11期20卷 1274-1278,1129页

作者：宋力平朱士正黄吉玲 School of Chemistry and Pharmaceutics East China University of Science and Technology Shanghai 200237 China Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Oxidation of aldehyde 4-chloro-2, 3,5, 6-tetrafluorophenylhydrazones (1) with [bis(acetoxy)iodo] benzene leads to the formation of nitrile imines (2) which can react in situ with acrylonitrile to produce l-(4-chloro-2,3,5,6-tetrafluorophenyl)-3-substituted-5-cyano-4, 5-dihydropyrazoles (3) in moderate to good yields. The structures of new compounds were fully confirmed by their spectral data and elemental analyses. A plausible reaction mechanism for the generation of nitrile imine is proposed.

关键词： 1,3-dipolar cycloaddition nitrile imine 4,5-dihydropyrazole derivative

Design, Synthesis and Properties of Novel C60-Crown Dyads by 1,3-dipolar cycloaddition

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Chemical Research in Chinese Universities 2014年第2期30卷 242-244页

作者： DI Xingdong YE Jinqi YANG Fafu GUO Hongyu YAN Xiaoyun College of Chemistry and Chemical Engineering Fujian Normal University Fuzhou 350007 P.R.China Fujian Key Laboratory of Polymer Materials Fuzhou 350007 P.R.China College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R.China

Based on the 1,3-dipolar cycloaddition of azomethine ylide generated in situ from aldehyde and sarcosine attached to C60,two novel benzo-15-crown-5/C60 dyads with a different linking chain in each were designed and synthesized in yields of 30％ and 38％,respectively.It was found that their UV-Vis absorption spectra could be regulated hypsochromically by metal ions complexed.The long and soft linking chain was favorable for cooperate interaction of crown ether unit and C60 unit.

关键词： C60 Benzo-15-crown-5 1,3-dipolar cycloaddition Complexation