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3-Benzoyl-2,3-dibromopropionic acid reacts with 4-substituted o-phenylenediamines to give 3-aryl-2-carboxymethylene-1,2-dihydroquinoxalines.  相似文献   

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Abstract

The formose reactions2 in N,N-dimethylformamide (DMF) catalyzed by 2-(dimethylamino)ethanol and thiamine hydrochloride, have been found to give rise to dihydroxyacetone and DL-glycero-tetrulose selectively at 1.1 M and 3.0 M of formaldehyde concentration, respectively. In our consecutive study on the formose reaction in DMF, it has been fortunately found that the distribution of products is able to be controlled by the amount of water added to the reaction mixture. We describe herein the first example of the favored formation of DL-2-C-hydroxymethyl-3-pentu-lose (GP-191) in the formose reaction using DMF-H2O solvent, and it's isolation and structure elucidation.  相似文献   

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Eleven aroylhydrazone derivatives of 3-benzoyl-5-formyl-2-methylpyrrole (3-13) have been prepared, and their 1H NMR, 13C NMR and mass spectral fragmentation arc discussed. Acetylation and oxidative cyclization to 1,3,4-oxadiazole mercuric complexes (17-20) were also carried out.  相似文献   

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合成了新的四氢叶酸辅酶(THF)模型化合物碘化1-甲基-2-异丙基-3-苯磺酰基咪唑啉(5a)和碘化1-甲基-2-丙基-3-苯磺酰基咪唑啉(5b),研究了其反应性能.结果表明,化合物5与双官能团亲核体邻苯二胺或邻氨基苯酚反应,完全转移了4个碳的异丁基和正丁基单元,基于此探索了合成2-取代苯并咪唑及2-取代苯并唑的新方法;化合物5a与单官能团亲核体胺类反应部分转移了4个碳的异丁基单元,生成不同基团取代的N,N,N'-三取代乙二胺盐;化合物5a在Na BH4作用下可发生还原反应,在Na OH水溶液中可发生水解反应,也可与碳负离子基团(硝基甲基负离子或二腈基甲基负离子)发生亲核加成反应,生成了3类不同基团取代的N,N,N'-三取代乙二胺衍生物,探索了此类化合物的简易合成方法.这些反应模拟了四氢叶酸辅酶在生物体内转移一碳单元的功能,并将其扩展到4个碳原子单元,获得了可应用于有机合成的新方法和新试剂.  相似文献   

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1 INTRODUCTION During the search of novel functional materials, much attention has been devoted to inorganic- organic hybrid compounds because of their capa- bility in offering important opportunities to combine the useful properties of organic compounds…  相似文献   

10.
陈鸿雁 《化学教育》2003,24(2):41-41
贵刊 2 0 0 1年第 9期刊登的《中学生化学实验设计初探》一文中 ,有这样一段文字 :在Fe2 + 和Fe3+ 相互转化试剂选择实验设计中 ,“我的学生用S2 - 来还原Fe3+ ,结果实验时发现有黑色的沉淀 ,还放出具有臭鸡蛋气味的气体 ,同学们对现象特别感兴趣 ,在课堂上引起了热烈的讨论 ,最后有几个成绩较好的学生来解释原因 :黑色沉淀是FeS ,放出H2 S气体是因为溶液中发生了双水解”。诚然 ,学生的学习热情和探究精神是值得表扬的 ,但是得出来的结论是偏颇的。我不知道该篇文章的作者熊辉 ,在当时是怎样引导和评价学生的。笔者经过做Na2…  相似文献   

11.
Selective methods were developed for the synthesis of 4-benzoyl-1-benzoylamino-3-(2-chlorophenyl)-2-cyano-1-methylthio-1-butene on the basis of the reaction of N-methylmorpholinium and piperidinium 5-benzoyl-4-(2-chlorophenyl)-3-cyano-6-hydroxy-6-phenyl-1,4,5,6-tetrahydropyridine-2-thiolates with methyl iodide. The structure of the product was established by X-ray crystallographic analysis.  相似文献   

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The reaction of 2-chlorobenzaldehyde with cyanothioacetamide and dibenzoylmethane in the presence of piperidine or N-methylmorpholine gave the corresponding 5-benzoyl-4-(2-chlorophenyl)-3-cyano-6-hydroxy-6-phenyl-1,4,5,6-tetrahydropyridine-2-thiolates, used in the synthesis of 1-alkylthio-4-benzoyl-1-benzoylamino-3-(2-chlorophenyl)-2-cyanobut-1-enes.  相似文献   

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Reformatsky reagents prepared from methyl 1-bromocycloalkanoates and zinc react with azomethines or azines to give 2,3-diaryl-2-azaspiro[3.5]nonan-1-ones, 2,3-diaryl-2-azaspiro[3.4]octan-1-ones or 2,2′ -bis(3-aryl-1-oxo-2-azaspiro[3.5]nonanes), respectively.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 629–631.Original Russian Text Copyright © 2005 by Kirillov, Shchepin.  相似文献   

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Reaction of 2,2-dialkyl-3-(dimethylamino)-2H-azirines 1a and 1b with 2,3-pyridinedicarboximide ( 4 ) in MeCN or DMF at room temperature yielded two regioisomeric tricyclic 1:1 adducts, the azacyclols 11/12 and 16/17 , respectively (Schemes 3 and 4). The structure of 12 was established by X-ray crystallography. Methanolysis of 11/12 and 16/17 led to mixtures of methyl [4, 4-dialkyl-5-(dimethylamino)-4H-imidazol-2-yl] pyridine carboxylates 13/14 and 18/19 , respectively. The structure of compound 14 is closely related to that of the powerful herbicide 9 (Scheme 9), i.e. the described reactions offer a new synthetic approach to this class of compounds. A mechanistic interpretation for the formation of regioisomeric 1:1 adducts as well as methyl (imidazol-2-yl) pyridine carboxylates is depicted in Scheme 5.  相似文献   

16.
2- and 3-furylmethanephosphonates are acylated with ethyl formate, diethyl oxalate, and ethyl trifluoroacetate in toluene in the presence of sodium foil to afford five phosphorylated derivatives of furylacetic aldehyde, furylpyruvic acid, and 1,1,1-trifluoro-1-(2-furyl)propan-2-one. In a chloroform solution these compounds exist in the equilibrium with their enolic forms. When treated with sodium ethylate they form sodium salts which were isolated and characterized by 1H, 13C, and 31P NMR spectroscopy. It was shown that in DMSO solutions sodium salts of formyl and oxalyl derivatives of 2-furylmethanephosphonate exist as mixtures of the carbanion and enolate forms. In the first case the carbanion form is predominant, while in the second one the enolate forms prevail. Sodium salt of formylated 3-furylmetanephosphonate exists only in the carbanion form, while the salt of 3-furylpyruvate is enolate. The alkylation of these salts with iodomethane proceeds at the carbon atom as well as at the oxygen one. First reaction pathway is often preferred.  相似文献   

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Biaryl-2-carboxylic acids have been prepared by palladium-catalyzed coupling reaction of 1-hydroxy-1,2-benziodoxol-3(1H)-one with arylboronic acids and arylborates with good yields under mild conditions.  相似文献   

18.
3-Alkenyl-5-chloropyrazoles reacted with alkanethiols on heating to 60°C to afford in good yields 3-[2-(alkylsulfanyl)ethyl]-5-chloropyrazoles as a result of anti-Markovnikov addition to the alkenyl group.  相似文献   

19.
Lili Zhang  Jing Sun  Chaoguo Yan 《中国化学》2013,31(12):1546-1550
The one-pot sequential reaction of arylamines, methyl propiolate and 2-aryl-3-nitrochromenes without any catalyst in refluxing ethanol afforded the polysubstituted 3-(3-nitro-2-phenylchroman-4-yl)-3-arylaminoacrylates in good yields and with high diastereoselectivity. Reaction mechanism was believed involving the initial formation of β-enamino ester and sequential Michael addition.  相似文献   

20.
1-苯甲酰基-1-甲硫基甲醇(2)与硫脲(3a)和芳基取代硫脲(3b-3i)在弱酸性条件下回流反应1h,得到5-苯基咪唑啉-2-硫酮-4-酮(4a)和1-芳基-5-苯基咪唑啉-2-硫酮-4-酮(4b-4i),产率72%~89%.而化合物2与芳胺(5a-5f)在弱碱性条件下回流反应3h,则得到2-芳胺基-2-甲硫基苯乙酮(6a-6f),产率为64%~88%.  相似文献   

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