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1 INTRODUCTION Biginelli reaction is a three-component condensa-tion of ethyl acetoacetate, benzaldehyde and urea forthe synthesis of 3,4-dihydropyrimidin-2(1H)-ones(Scheme 1). The reaction can be carried out in aone-pot fashion in alcohol solution in t… 相似文献
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LI Qian-rong XUE Song YIN Hao 《高等学校化学研究》2006,22(1):40-44
IntroductionIn1893,Pietro Biginelli reported the first synthe-sis(termed the Biginelli reaction)of3,4-dihydropyrim-idinone(denoted as“oxo-orO-Biginelli compound”in-cluding its derivatives,type A in Scheme1).In thelast decade,interest in these compounds … 相似文献
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Biginelli反应是约120年前意大利化学家Pietro Biginelli发现的,所涉及的就是乙酰乙酸乙酯、尿素和芳基醛的一锅酸催化环化缩合反应.大量的研究表明Biginelli反应的产物——二氢嘧啶酮类化合物因为具有显著的生理和药理活性以及结构变化的多样性使得人们对于Biginelli反应的关注度持续增高.讲述了在微波无溶剂条件下,通过醛、对甲基苯甲酰丙酮、尿素(硫脲)在对甲苯磺酸催化下进行的Biginelli反应的方法来合成5-(4-甲基苯甲酰基)-3,4-二氢嘧啶-2(1H)-酮(硫酮)类衍生物,不仅易得到且收率高. 相似文献
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屠树江   朱晓彤   房芳   章晓镜   朱松磊   李团结   史达清 王香善   纪顺俊 《中国化学》2005,23(5):596-598
A simple effective synthesis of bis(dihydropyrimidinone-4-yl)benzene derivatives, using boric acid as catalyst,from isophthalic aldehyde or terephthalic aldehyde, 1,3-dicarbonyl compounds and urea or thiourea in glacial acetic acid was described. As the expansion of the classical Biginelli reaction, this method has the advantage of excellent yields 83%-94% and short reaction time 0.5-1.5 h. 相似文献
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Silica-bonded N-propyl sulfamic acid(SBNPSA) catalyzed one-pot three component Biginelli condensation of different substituted aromatic aldehydes with ethyl acetoacetate and urea/thoiurea to the respective 3,4-dihydropyrimidin-2-(1H)-ones and thiones in environment friendly procedure is described. The facile reaction conditions, simple isolation and purification procedures of this method make it a good option for the synthesis of dihydropyrimidinones. 相似文献
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A one-pot three component Biginelli condensation of different substituted aromatic and aliphatic aldehydes with ethyl acetoacetate and urea to the respective 3,4-dihydropyrimidin-2-( 1H)-ones under sol... 相似文献
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A general and practical procedure for the syntheses of 3,4-di-hydropyrimidine-2(1H)-thiones by a one-pot condensation of aldehyde,β-ketoester or β-diketone and thiourea using La(OTf)3 as the catalyst is described.Mild reaction conditions,excellent yields as well as the environmentally friendly character of La(OTf)3 make it an important alternative to the classic acid-catalyzed Biginelli‘s reaction. 相似文献
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标题化合物是由5-(R)-(l-孟氧基)-2(5H)-呋喃酮与3,4-亚甲二氧基苯甲醛肟在次氯酸钙作为氧化剂的条件下,进行的区域选择性原位1,3-偶极环加成反应得到。结构通过单晶X-射线衍射法确定, C22H27NO6其晶体属正交晶系, 空间群为P212121, Mr = 401.45, a = 6.2600(3), b = 10.7300(11), c = 31.2160(25) , V = 2096.8(3) 3, Z = 4, Dc = 1.272 g/cm3, μ = 0.09 mm-1, F(000) = 856。最终的可靠因子为R f = 0.073, wR = 0.186。在分子结构中,平面1(异噁唑啉环)与平面2(呋喃酮环)之间的二面角为67.4°, 孟氧基中的环己烷环为椅式构象,呋喃酮并异噁唑啉环上的3个手性中心的构型为SC3a, RC6, RC6a。 相似文献
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微波辐射下4-胡椒基-2,6-二甲基-3,5-乙氧羰基-1,4-二氢吡啶的合成、芳构化及产物的晶体结构 总被引:1,自引:0,他引:1
用胡椒醛、乙酰乙酸乙酯和醋酸铵在微波辐射下干反应得4-胡椒基-2,6-二甲基-3,5-乙氧羰基-1,4-二氢吡啶 1(C20H23NO6),4-胡椒基-2,6-二甲基-3,5-乙氧羰基-1,4-二氢吡啶在NDC (烟酸三氧化铬) 存在下经微波辐射得到4-胡椒基-2,6-二甲基-3,5-乙氧羰基吡啶 2 (C20H21NO6)。产物的结构通过单晶X-射线衍射法确定, 1 属单斜晶系, 空间群P21/c, a = 14.864(3), b = 9.830(1), c = 14.517(3)? b = 115.25(1), V = 1918.6(6)?, Z = 4, Mr = 373.39, Dc = 1.293g/cm3, m(MoKa)=0.096mm-1, F(000)=792。最终的偏离因子为R = 0.0496, wR = 0.1368。2 属三斜晶系,空间群Pī, a = 8.915(1), b = 10.575(1), c = 11.904(1)?α = 102.19(1),b = 109.43(1),γ=108.94(1), V=934.79(16) 3, Z = 2, Mr = 371.38, Dc = 1.319g/cm3 , m(MoKa) = 0.098mm-1, F(000) = 392。最终的偏离因子为R=0.0412, wR=0.1011。1 的二氢吡啶环为信封式结构, 2的吡啶环为平面结构。 相似文献
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1 INTRODUCTION 2-Aminochromene is an important class of com- pounds found as the main compounds of many natu- rally occurring products employed as cosmetics and pigments and utilized as potential biodegradeable agro- chemicals[1~3]. In recent years, montmorillonite in natural and ex- changed forms has received considerable attention in different organic syntheses because of its environ- mental compatibility, low cost, high selectivity, reusa- bility and operational simplicity[4], such as … 相似文献
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Taylor J Vargas W Torvisco A Ruhlandt-Senge K Spencer JT 《Dalton transactions (Cambridge, England : 2003)》2011,40(40):10585-10591
The reaction of cyanogen chloride with [1-(4-C(7)H(7))-12-(C(5)H(3)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (7) was found to yield two new C(5)-substituted carborane cluster-based compounds, [1-(4-C(7)H(7))-12-(C(5)H(2)-3-(CN)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (8) and [1-(4-C(7)H(7))-12-(C(5)H-2,4-(CN)(2)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (9). This cyano-substitution pattern is in contrast to the known substitution for the analogous organic quinarene[5.6.7] system. The observed unique cluster-based products may be understood by a combination of steric and electronic effects. Compounds 8 and 9 were characterized by complete multinuclear NMR, (1)H-(1)H COSY NMR, (1)H-(13)C HMQC NMR, FTIR, UV-Vis, IR, MS data and a single crystal analysis for 8 [X-ray data for 8: C(17)H(25)B(10)N, monoclinic, space group P2(1)/n with cell constants a = 8.6794(17) ?, b = 11.021(2) ?, c = 43.175(9) ?, β = 91.00(3)°, V = 4129.2(14) ?(3), Z = 8, R(1) = 0.0729, wR(2) = 0.1464]. 相似文献
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The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 相似文献
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1 INTRODUCTION The title compound, (3aS,6aR)-1.3-dibenzyl- tetrahydro-1H-thieno[3,4-d]-imidazole-2(3H)-one- 4-ylidenepentanoic acid 3, is a key intermediate for the synthesis of d-biotin 1 (VITH, Fig. 1) which has been widely used not only as a pharmaceu… 相似文献
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1INTRODUCTION It has been reported that3,6-disubstituted-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines have a broad spec-trum of bioactivities,such as antimicrobial[1],antibac-terial,antifungal[2],anti-inflammatory[3],diuretic[4],an-thelmintic and analgesic[5].They can also be used as plant-growth regulating agents[6],photographic coup-lers,dyes for improved preservability and absorption characteristics,and inhibitors of malignant cellularZOU K.H.et al.:Syntheses and Crystal Structures o… 相似文献
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ZOU Kai-huang ZHANG Li-xue ** ZHANG An-jiang LEI Xin-xiang HUANG Hui-hua ZHANG Zi-yi . School of Chemistry Materials Science Wenzhou Normal College Wenzhou P. R. China . Department of Biology Chemistry Fujian Educational College Fuzhou P. R. China . College of Chemistry Chemical Engineering Lanzhou University Lanzhou P. R. China 《高等学校化学研究》2005,21(1):69-72
Introduction3,6- Disubstituted- 7H- 1 ,2 ,4- triazolo[3,4- b][1 ,3,4]thiadiazines are amongst the various hete-rocycles that received considerable attention duringthe last two decades as potential biologically activeagents.This kind of N- bridged heterocycles hasbeen reported to possess the wide spectrum of bio-logical properties,such as antimicrobial[1] ,an-tibacterial,antifungal[2 ] ,antiinflammatory[3 ] ,di-uretic[4] ,anthelmintic,and analgesic properties[5] .They can be also used as plant… 相似文献