检索结果-南通市图书馆

Organic Chemistry Frontiers 2022年第1期9卷 51-57页

作者： Fang Sun Fangfang Lu Xue Song Wenchao Wu Kai Zhang chenxia yu Tuanjie Li Donghui Wei Changsheng Yao Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhouJiangsu 221116P R China. The College of Chemistry and Molecular Engineering Zhengzhou University100 Science AvenueZhengzhouHenan 450001P R China

An NHC-catalyzed regiospecific allylation ofα-substituted allenoates with MBH carbonates derived from aryl aldehyde furnished highly functionalized 1,5-enynes bearing a quaternary carbon *** with DFT calculations,the reaction mechanism of this conversion was *** method has the advantages of high regioselectivity,good yields and mild reaction *** transformation not only provided a new access to 1,5-enyne,but also enriched the chemistry of allenoates and NHC catalysis.

关键词： conditions catalysis allyl

Asymmetric cascade syntheses of heterocycles catalyzed by NHC

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asymmetric cascade syntheses of heterocycles catalyzed by NH...

中国化学会第十四届全国有机合成化学学术研讨会

作者： Tuanjie Li chenxia yu Changsheng Yao School of Chemistry and Materials Science Jiangsu Normal University

Over the past several decades,N-heterocyclic carbenes (NHCs) have evolved into a powerful kind catalysts for organic *** from the classical polarity of aldehyde (a-d)and enal (a-d),ring-opening polymerization and transesterification could also be promoted by ***,much effort has been devoted to the generation and reactivity of NHC-bounded intermediates such as homoenolate,vinyl enolate,α,β-unsaturated azolium and azolium enolate converted from functionalized aldehyde and ***,we would like to report our recent study on the NHC-catalyzed formation of these key intermediates from readily available starting materials includingα-bromoenal,α,β-unsaturated carboxylic acids and their derivatives and the subsequent asymmetric [3+2],[3+3]or [4+2] annulation to construct heterocyclic scaffolds with biological potential.

关键词： N-heterocyclic carbene cascade synthesis heterocycles

基于能源消耗周期的我国低碳城市发展模式研究

在线全文

cnki会议

学校读者我要写书评

暂无评论

干旱区资源与环境 2017年第9期31卷 20-25页

作者：赵涛于晨霞潘辉天津大学管理与经济学部天津300072 天津城建大学经济与管理学院天津300384

为了实现节能减排目标,构建低碳城市已经成为未来城市发展的重要路径选择。我国正处于城镇化加速发展时期,城市差异性特征决定了低碳城市发展的方法和途径不同,必须探索适合自身的发展模式。文中基于城市能源消耗周期视角,选取6个评价指... 详细信息

为了实现节能减排目标,构建低碳城市已经成为未来城市发展的重要路径选择。我国正处于城镇化加速发展时期,城市差异性特征决定了低碳城市发展的方法和途径不同,必须探索适合自身的发展模式。文中基于城市能源消耗周期视角,选取6个评价指标,以我国35个副省级以上城市作为研究对象,采取2010-2014年的面板数据,通过自组织竞争神经网络法进行聚类分析,将35个城市划分为清洁能源型、能源消耗型、碳汇型和混合型四类发展模式,然后利用SYS-GMM方法对各类模式进行显著性分析,提出差异化的低碳城市发展模式及政策建议。

关键词：低碳城市发展模式面板聚类分析神经网络系统广义矩估计

An NHC-catalyzed assembly of spirocyclic oxindole-cyclopentene

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An NHC-catalyzed assembly of spirocyclic oxindole-cyclopente...

中国化学会第十三届全国有机合成化学学术研讨会

作者： Jiang Ligen Que Yonglei Li Tuanjie yu chenxia Yao Changsheng School of Chemistry and Chemical Engineering Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal University

The spirocyclic oxindole-cylopentene skeletons featured in a large number of nature products have potential biological ***,various approaches such as phosphine catalysis,and metal-mediated multistep transformations,have been performed to realize the successful assembly of ***,the lengthiness of synthetic route and complexity of the starting materials necessitate the developement of new telescoped protocol to construct this *** synthesis of diverse cyclopentenes utilizing different unsaturated aldehydes and α,β-unsaturated ketones catalyzed by N-Heterocyclic Carbene（NHC） has been reported by Nair and *** envisioned that the conversion of α-enal and NHC into NHC-bounded homoenolate and the following cyclization with the oxindole-derived α,β-unsaturated ketone may pave a new avenue to the spirocyclic oxindole-cylopentene.

关键词： N-Heterocyclic Carbene spirocyclic oxindole-cylopentene

NHC-Catalyzed Three-Component Domino Reaction of Bromoenals with Oxindoles: Diastereoselective Assembly of Spirooxindole 4H-Pran-2-Ones

在线全文

cnki会议

学校读者我要写书评

暂无评论

NHC-Catalyzed Three-Component Domino Reaction of Bromoenals ...

中国化学会第十四届全国有机合成化学学术研讨会

作者： Yong Hu Baomin Sun chenxia yu Tuanjie Li Shujiang Tu Changsheng Yao School of Chemistry and Materials Science Jiangsu Normal University

Spirooxindoles are frequently present as important cores in large amounts of natural products,pharmaceutically relevant synthetic compounds with highly biological activities. As a novel class of spirooxindoles, only a few investigations have been focused on the syntheses and bioactivities of spirooxindole 4H-pyran-2-ones. N-heterocyclic carbene(NHC)catalysis has been used as a powerful tool for a large number of untypical chemical transformations. Among these conversions,α,β-unsaturated acyl azoliums have emerged as fascinating1,3-biselectrophile synthons with unique and unprecedented chemistry that were pioneered by Zeitler in 2006. The well-explored reactions involved NHC-mediated formal[3+3]annulations ofα,β-unsaturated acyl azoliums with various 1,3-bisnucleophiles to afford functionalized dihydropyranones and dihydropyridinones. However,to the best of our knowledge,the three-component domino reaction of bromoenals are rarely *** continuation of our studies on the exploration of NHC-catalyzed annulations for the synthesis of diverse heterocyclic systems, we shall herein report that oxindoles serve as 1,1-bisnucleophiles to undergo three-component domino reaction,which provides a new access to spirooxindole 4H-pyran-2-ones.

关键词： spirooxindoles N-heterocyclic carbenes α,β-unsaturated acyl azloliums

N-Heterocyclic Carbene-Catalyzed[4+2]Cyclization of α-bromo-enal with 3-alkylenyloxindoles:an efficient synthesis of spirocyclic oxindoles

在线全文

cnki会议

学校读者我要写书评

暂无评论

N-Heterocyclic Carbene-Catalyzed[4+2]Cyclization of α-bromo...

中国化学会全国第十一届有机合成化学学术研讨会

作者： yuanwei Xie Zhaoxin Xiao Tuanjie Li Rui Liu chenxia yu Changsheng Yao School of Chemistry and Chemical Engineering Jiangsu Normal University

N-heterocyclic carbene(NHC) catalyzed reactions have emerged as an particularly fruitful area of research in organic chemistry. Due to the unique "Umpolung" in organic synthesis,umpoluping the aldehydes to acyl nucleophiles has become an important way to synthesis of heterocyclic compounds in current research. Spirooxindole cores are interesting and important structures found in many bioactive natural products,and the functionalized six-membered spirooxindole core structure is featured in many natural products as well as medicinally relevant compounds. Herein we shall report our preliminary results of an NHC-catalyzed reaction of 2-bromo-2-enal bearing γ-H with 3-alkylenyloxindoles,which may give the desired spirocarbocyclic oxindoles with potential bioactivity.

关键词： NHC spirocyclic oxindole α-bromo-enal 3-alkylenyloxindole

A Stereoselective Assembly of Dihydropyranone through NHC/LiCl-catalyzed in situ Activation of α,β-Unsaturated Carboxylic

在线全文

cnki会议

学校读者我要写书评

暂无评论

A Stereoselective Assembly of Dihydropyranone through NHC/Li...

中国化学会第九届全国有机化学学术会议

作者： Yonglei Que chenxia yu Tuanjie Li Xiang-Shan Wang Shide Shen Changsheng Yao Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials School of Chemistry and Chemical EngineeringJiangsu Normal University Xuzhou Institute of Architectural Technology

＜正＞The carboxylic acids are readily available,more stable compared with enal and the functionalized aldehydes includingα-aryloxy acetal aldehydes and halogenated aldehydes employed previously in NHC-catalyzed ***,they are less liable to generate enolate than ketones and activated esters,which may avoid some side reactions such as Aldol reaction and Michael reaction.

关键词：

An NHC-catalyzed Oxidative γ-Aminoalkylation of Saturated Carboxylic Acids through in situ Activation Strategy:A New Access to δ-Lactam

在线全文

cnki会议

学校读者我要写书评

暂无评论

An NHC-catalyzed Oxidative γ-Aminoalkylation of Saturated C...

中国化学会第九届全国有机化学学术会议

作者： Yonglei Que yuanwei Xie Tuanjie Li chenxia yu Shujiang Tu Changsheng Yao School of Chemistry and Chemical Engineering Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal University

Carboxylic acids y are less liable to enolize than ketone and activated esters,which may avoid the occurrence of the side reaction including aldol condensation,Michael addition and Claisen *** noticeable advantages make the carboxylic acids ideal starting materials for organic synthesis and considerable attention has been focused on their organocatalytic transformations.

关键词：

应用微波辐射技术一步合成4-芳基-1,4-二氢吡啶衍生物

在线全文

cnki会议

学校读者我要写书评

暂无评论

有机化学 2002年第4期22卷 269-271页

作者：屠树江高原于晨侠史达清徐州师范大学化学系徐州221009 深圳大学化学系深圳518060

以芳醛、乙酰乙酸乙酯、醋酸铵为原料在无溶剂条件下应用微波技术合成了 4 芳基 2 ,6 二甲基 3 5 二乙氧羰基 1,4 二氢吡啶 ,该反应在 2～ 5min内完成 ,产率 73%～ 99% .

关键词：微波辐射 4-芳基-1,4-二氢吡啶衍生物合成芳醛乙酰乙酸乙酯醋酸铵

氮杂环卡宾(NHC)/银(I)共催化合成2-氧代-2-芳乙基芳甲酸酯

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

有机化学 2021年第4期41卷 1607-1613页

作者：成立王文蓉孙玉倩李团结于晨侠姚昌盛江苏师范大学化学与材料科学学院江苏省功能材料绿色合成重点实验室江苏徐州221116

在氮杂环卡宾(NHC)/银(I)的共催化下,以芳醛和(溴乙炔)苯及其衍生物为原料实现了2-氧代-2-芳乙基芳甲酸酯高效合成.该方法具有底物范围广、原料简单易得、操作简便等优点,为α-酰氧基羰基衍生物的简捷合成提供了新思路.

关键词：氮杂环卡宾(N-heterocyclic,carbene,NHC) 银(I) 共催化 α-酰氧基酮