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1.
3-取代和3,4-二取代噻吩的合成与表征   总被引:4,自引:0,他引:4  
以噻吩、48% (m/m)氢溴酸水溶液、35% (m/m)过氧化氢水溶液、高纯氨、金属钠为原料合成了3-溴噻吩和3,4-二溴噻吩,3-溴噻吩和3,4-二溴噻吩分别以(dppp)NiCl2为催化剂合成了3-烷基噻吩和3,4-二烷基噻吩.3-溴噻吩以CuI, NaHSO4为催化剂合成了3-烷氧基噻吩,产率较高.并用核磁共振谱、质谱和元素分析方法进行了表征.  相似文献   

2.
很容易从醛和四溴化碳及三苯膦反应制备的1,1-二溴-1-烯烃在有机合成中是一个非常重要的原料.它广泛地应用于在钯催化下与有机硼酸、有机锡化合物、炔烃、有机锌试剂和Grignard试剂的交叉偶联反应[1-4].除此之外,1,1-二溴-1-烯烃与三丁基锡化氢的氢解反应,1,1-二溴-1-烯烃被氢负离子的还原,1,1-二溴-1-烯烃与金属钐和二碘化钐进行的还原脱溴反应,1,1-二溴-1-烯烃与胺的反应业已报道[5,6].Shen近来研究了钯催化下1,1-二溴-1-烯烃在不同膦配体的存在下于DMF溶液中的自身偶联反应和与末端炔烃的交叉偶联反应[7].  相似文献   

3.
水合茚三酮与芳甲基酮、水合肼缩合环化制得2-芳基-3,4-二氮杂芴酮(2); 2经还原得2-芳基-3,4-二氮杂芴(3).2与2-溴联苯格氏试剂反应得到中间体叔醇(4); 4在酸性条件下关环合成了2-芳基-3,4-二氮杂螺二芴,其结构经1H NMR,13C NMR和元素分析表征.  相似文献   

4.
张若思  刘建军  屈莹  左胜利 《合成化学》2013,(4):458-460,464
在无溶剂条件下,1,6-亚甲基桥[10]轮烯-3,4-二甲酸酐与尿素反应制得1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺(2);2与KOH的甲醇溶液于常温反应得1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺钾(3);3与氯甲酸酯反应合成了4个新型的N-酯基取代的1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺,其结构经1H NMR,13C NMR,IR,MS和HR-MS表征。  相似文献   

5.
β-(3,4-二甲氧基)苯乙胺与甲醛及甲酸在封管中热至125°,生成N,N-二甲基衍生物.2-溴-1-(3,4-二甲氧基)苯乙烷与二乙胺或六氢吡啶缩合则成相应N,N-二乙基衍生物或N-六氢吡啶衍生物.在无水碳酸钠作用下,N-甲基-β-(3,4-二甲氧基)苯乙胺经氯化苄、2-溴-1-苯乙烷或2-溴-1-(3,4-二甲氧基)苯乙烷烷化,分别生成相应N-甲基-N-芳烷基-β-(3,4-二甲氧基)苯乙胺.β-(3,4-二甲氧基)苯乙胺经乙酸酐或苯乙酰氯酰化后,再以五氧化二磷环化,并以锌粉及盐酸还原,分别制成1-甲基及1-苄基-6,7-二甲氧基-1,2,3,4-四氢异喹啉.以上制成的化合物均可认为是镇痛药延胡索素乙的裂环化合物,并已进行药理试验.  相似文献   

6.
1,1-二溴-1-烯烃作为一类重要的有机合成原料和中间体,已被应用于C—C、C—N、C—O、C—P和C—S键的构建.二溴烯烃分子中包含一对活泼的C—Br键,使其在制备溴代烯烃、溴代炔烃、端炔和通过经典的偶联反应制备多取代的烯烃、内炔和稠环化合物等的反应中应用广泛.综述了1,1-二溴-1-烯烃在有机合成中的研究进展.  相似文献   

7.
赵頔  刘延鹰  王洋  李阳 《化学通报》2023,86(5):589-597
本文设计以2-溴甲基喹啉-3,4-二甲酸二乙酯为起始化合物,经一锅连续的Arbuzov反应/Horner-Wadsworth-Emmons(HWE)反应过程,简便而有效地合成了一系列结构新颖的(E)-2-苯乙烯基喹啉-3,4-二羧酸二乙酯类衍生物(3a~3i),其结构均已通过波谱数据和元素分析得以证实。  相似文献   

8.
以1,6-亚甲基桥[10]轮烯-3,4-二乙酯为原料,简便地合成了二甲酸酐(2);2与肼在氮气保护下,无溶剂于170 ℃反应30 min,以较高收率合成了4个新型N-氨基取代的1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺,其结构经1H NMR, 13C NMR, MS及HR-MS表征.  相似文献   

9.
韦丽  杨晓丽  袁吉文  胡宏纹  陆国元 《有机化学》2012,32(12):2339-2343
考布他汀-A4(Combretastatins-A4,CA-4)是从天然产物中分离得到的抗癌活性化合物,其分子中Z-构型烯键易异构化转变为无抗癌活性的E-构型.以吡咯-2,5-二酮或吡咯-2-酮代替烯键,设计合成了4个新的CA-4类似物.它们的合成是以3,4-二甲氧基苯乙酮或3-氟-4-甲氧基苯乙酮为起始原料,经α-溴化、改良的Gabriel合成法、与3,4,5-三甲氧基苯乙酸缩合、环化-氧化或环化四步反应完成.其结构用1H NMR,13C NMR,ESI-MS及元素分析进行了表征.用MTT法测试了CA-4类似物对人白血病细胞HL-60、肝癌细胞SMMC-7721和肺腺癌细胞A549的体外抗肿瘤活性.初步结果表明,含氟化合物3,4-二芳基-2,5-吡咯酮(1b)的抗肿瘤活性接近CA-4,IC50值达到0.03~0.05μmol·L-1.  相似文献   

10.
刘太奇  杨莉燕  于建香 《有机化学》2007,27(10):1282-1284
在冰浴条件下, 2-甲基噻吩(1)与液溴反应生成3,5-二溴-2-甲基噻吩(2); 在-78 ℃条件下, 硼酸三丁酯加入2, 得到2-甲基-3-溴-5-硼酸基噻吩(3); 3,4-二氟溴苯与3反应得到2-甲基-3-溴-5-(3,4-二氟苯基)噻吩(4); 在-78 ℃下全氟环戊烯与4反应, 得到一种新的二芳基乙烯类光致变色化合物1,2-双[2-甲基-5-(3,4-二氟苯基)噻吩-3-基]全氟环戊烯(DT-1). 用IR, NMR, MS和元素分析确定了化合物DT-1的结构, 并对该化合物的光致变色特性进行了初步研究.  相似文献   

11.
Oxidation reactions of 2,5- and 3,6-di-tert-butyl-3H-azepines (1 and 2) with selenium dioxide (SeO(2)) were performed. The oxidation of 1 with SeO(2) gave 3-tert-butyl-7,7-dimethyl-4-oxo-octa-2,5-dienal 3 in 36% yield, 4-tert-butyl-5-(3,3-dimethyl-2-oxo-butylidene)-1, 5-dihydro-pyrrol-2-one 4 in 13% yield, 2, 6-di-tert-butyl-2-pyridinecarbaldehyde 5 in 12% yield, and 4, 7-di-tert-butyl-2H-azepin-2-one (2-azatropone) 6 in 6% yield, respectively. Oxidation of 2 with SeO(2) gave 2, 2-dimethyl-1-[2-(5-tert-butyl)-pyridyl]propanol 7 in 55% yield, and 3,6-di-tert-butyl-2H-azepine 8 in 5% yield, respectively. We found that selenium dioxide oxidation of 1 affords 4-oxo-octa-2,5-dienal 3 by a new ring cleavage reaction of 1, and we described the first synthesis of 2-azatropone 6 from this oxidation of 1. In the case of 2, pyridylpropanol 7 was obtained as the major product. We now report in detail result of these oxidation reactions, which have led to the synthesis of a novel azatropone derivative.  相似文献   

12.
王洋  卢美艳  夏鹏 《有机化学》2003,23(12):1396-1399
以1-萘酚(6)为起始原料,经过Birch还原得到5,8-二氢-1-萘酚(7);7与乙酰 乙酸乙酯在不同条件下缩合合成了4-甲基-7,10-二氢苯并[h]香豆素(4).研究结 果表明,无氧和酸催化的反应条件对缩合反应是至关重要的.在没有酸催化的条件 下,反应生成3-乙酰基-2-羟基-6-甲基-吡喃-4-酮(8),并通过单晶X射线衍射分析 确定了产物的结构;在酸催化的条件下,除了生成产物4外,还伴随生成脱氢芳构 化产物4-甲基苯并[h]香豆素(5),而且在不同条件下二者的比例不同,其中以甲磺 酸为催化剂、在氮气保护下并加入抗氧化剂无水Na_2SO_3为最佳反应条件,化学选 择性约为70:30(4:5),收率49.1%.  相似文献   

13.
The nitration of 5-chloropyrazoles with a mixture of 100% nitric acid and 65% oleum or a mixture of 60% nitric acid and polyphosphoric acid gave substituted 5-chloro-4-nitropyrazoles in 45–91% yield. The nitration of 3-aryl-5-halopyrazoles was accompanied by introduction of a nitro group into the aromatic ring. 4-Chloropyrazoles failed to undergo nitration under these conditions. The reaction of 5-chloro-1,3-dimethyl-4-nitropyrazole with ethyl cyanoacetate in DMSO in the presence of K2CO3 led to the formation of ethyl 2-cyano-2-(1,3-dimethyl-4-nitro-1H-pyrazol-5-yl)acetate.  相似文献   

14.
The reaction of 4,4-dimethyl-3-oxobutanoic (or pentanoic) acid esters with the lactim ether of 2-pyrrolidone in the presence of 2-hydroxypyridine produces condensation products 4 in 57–72% yield. Acidic hydrolysis of 4 affords the furandione system 5 in 75–81% yield.  相似文献   

15.
Heterocyclic and Carbocyclic 12-π-and 14-π-Systems, 47th Commnunication1. Synthesis of 7,9-Dimethyl-4,5-dihydro-3H-benz[cd]azualene-3-one and 7,9-Dimethyl-3H-benz[cd]azulene-3-one. A Simple Synthesis of Azulenopseudophenalenons 4, 6, 8-Trimethylazulene ( 3 ) reacts after metalation with lithiumdiisopropyl-amide in ether with bromoacetic acid to the 6, 8-dimethylaltulene-4-propionic acid ( 4 ), which undergoes cyclization to the 7, 9-dimethyl-4, 5-dihydro-3H-benz [cd]-azulene-3-one ( 5 ) in the presence of p-toluenesulfonic acid; oxidation of 5 with 2, 3-dichloro-5, 6-dicyanobenzoquinone yields 7, 9-dimethyl-3H-benz [cd]azulene-3--one ( 1b ). Alkylation of 1b with triethyloxonium tetrafluoroborate in CH2C12 gives the 3-ethoxy [cd]benzazulenium tetrafluoroborate ( 6 ).  相似文献   

16.
A method was developed to prepare 5′-deoxy-5′-substituted-ψ-uridine derivatives 4 from 3′,5′-O-(1, 1, 3, 3-tetraisopropyldisiloxanyl)-1,3-dimethyl-ψ-uridine 1 via a silyl rearrangement reaction. Nucleophilic displacement of the mesyloxy function of 2′-O-mesyl-1,3-dimethyl-ψ-uridine 7 afforded products with the 2′-substituent in the “down” ribo configuration 8 . X-Ray crystallographic analysis of the 2′-chloro derivative 8a firmly established the molecular structure of 8 and provided evidence for neighboring group participation of the 4-carbonyl function of 7 during the nucleophilic reactions. Treatment of 1,3-dimethyl-ψ-uridine 11 with α-acetoxyisobutyryl chloride afforded a mixture from which two 2′-chloro-2′-deoxy-C-nucleosides were obtained. The major product (33% yield) was identical with 8 . The minor product (7% yield) was consequently assigned the arabino nucleoside 14 . This is the first direct introduction of a 2′-substituent in the “up” configuration in a preformed pyrimidine nucleoside.  相似文献   

17.
Alkylation of the sodium salt of mesitol with 2-bromomethyl-buta-1,3-diene ( 7 ) in benzene and subsequent refluxing of the reaction mixture gave 7% 2-methylene-3-butenyl-mesitylether ( 8 ), 12% 5-methylene-1,3,8-trimethyl-tricyclo[4,3,1,03,7]-8-decen-2-one ( 9 ) and 44% 9-methylene-1,3,5-trimethyl-tricyclo[4,4,0,03,8]-4-decen-2-one ( 10 ), a twistane derivative. The same procedure, when applied to the sodium salt of 2,6-dimethyl-4-methoxyphenol, gave in 73% yield a 26:18:54 mixture of 2,6-dimethyl-4-methoxyphenyl-(2-methylene-3-butenyl)-ether ( 11 ), 1,3-dimethyl-8-methoxy-5-methylene-tricyclo[4,3,1,03, 7]-8-decen-2-one ( 12 ), and 1,3-dimethyl-5-methoxy-9-methylene-tricyclo[4,4,0,03, 8]-4-decen-2-one ( 13 ). The tricyclic ketones 9 and 10 , or 12 and 13 , were also obtained on heating 8 or 11 respectively at 176° in decane solution. Alkylation of the sodium salt of 2,6-dimethylphenol with 3-butenylbromide in boiling toluene gave 1,3-dimethyl-tricyclo[4,3,1,03,7]-8-decen-2-one ( 17 ) as the only tricyclic product in 8% yield. The structures of the twistane derivatives 10 and 13 as well as those of the ketones 9, 12 and 17 were mainly deduced from spectroscopic data. Furthermore, the ketones 10 and 13 could be converted to the twistane derivatives 20 and 22 , possessing C2-symmetry. On the other hand, compounds 9 and 17 gave only the asymmetric derivatives 18 and 21 .  相似文献   

18.
On the Synthesis of Sulfonated Derivatives of 2,3-Dimethylaniline and 3,4-Dimethylaniline Baking the hydrogensulfate salt of 2,3-dimethylaniline ( 1 ) or of 3,4-dimethylaniline ( 2 ) led to 4-amino-2,3-dimethylbenzenesulfonic acid ( 4 ) and 2-amino-4,5-dimethylbenzenesulfonic acid ( 5 ), respectively (Scheme 1). The sulfonic acid 5 was also obtained by treatment of 2 with sulfuric acid or by reaction of 2 with amidosulfuric acid. 3-Amino-4,5-dimethylbenzenesulfonic acid ( 3 ) and 5-Amino-2,3-dimethylbenzenesulfonic acid ( 6 ) were prepared by sulfonation of 1,2-dimethyl-3-nitrobenzene ( 9 ) to 3,4-dimethyl-5-nitrobenzenesulfonic acid ( 11 ) and of 1,2-dimethyl-4-nitrobenzene ( 10 ) to 2,3-dimethyl-5-nitrobenzenesulfonic acid ( 12 ), respectively, with subsequent Béchamp reduction (Scheme 1). Preparations of 2-amino-3,4-dimethylbenzenesulfonic acid ( 7 ) and of 6-amino-2,3-dimethylbenzenesulfonic acid ( 8 ) were achieved by the sulfur dioxide treatment of the diazonium chlorides derived from 3,4-dimethyl-2-nitroaniline ( 24 ) and from 2,3-dimethyl-6-nitroaniline ( 31 ) to 3,4-dimethyl-2-nitrobenzenesulfonyl chloride ( 29 ) and 2,3-dimethyl-6-nitrobenzenesulfonyl chloride ( 32 ), respectively, followed by hydrolysis to 3,4-dimethyl-2-nitrobenzenesulfonic acid ( 30 ) and 2,3-dimethyl-6-nitrobenzenesulfonic acid ( 33 ), and final reduction (Scheme 3). Compound 7 was also synthesized by reaction of 4-chloro-2,3-dimethylaniline ( 23 ) with amidosulfuric acid to 2-amino-5-chloro-3,4-dimethylbenzenesulfonic acid ( 20 ) and subsequent hydrogenolysis (Scheme 2). 4′-Bromo-2′, 3′-dimethyl-acetanilide ( 13 ) and 4′-chloro-2′, 3′-dimethyl-acetanilide ( 14 ) on treatment with oleum yielded 5-acetylamino-2-bromo-3,4-dimethylbenzenesulfonic acid ( 17 ) and 5-acetylamino-2-chloro-3,4-dimethylbenzenesulfonic acid ( 18 ), respectively. Their structures were proven by hydrolysis to 5-amino-2-bromo-3,4-dimethylbenzenesulfonic acid ( 21 ) and 5-amino-2-chloro-3,4-dimethylbenzenesulfonic acid ( 22 ), followed by reductive dehalogenation to 3 .  相似文献   

19.
Reaction of 3-Dimethylamino-2,2-dimethyl-2H-azirine with Barbituric Acid The reaction of 3-dimethylamino-2,2-dimethyl-2H-azirine (1) with barbituric acid (4) in dimethyl formamide at room temperature yields a mixture of several compounds. The two main products 5 and 6 have been isolated in 40 and 10% yield, respectively, and their structures established by X-ray analysis. In Schemes 4–6 reaction mechanisms for the formation of 5 and 6 are postulated, the first step beeing either a C- or an N-alkylation of barbituric acid. Reduction of 5 and 6 with NaBH4 in ethanol at room temperature yields 6,6-dimethyl-1,5,6,7-tetrahydro-pyrrolo[2,3-d]pyrimidin-2,4(3H)-dione (7) and 3,3-dimethyl-2,3-dihydro-imidazo[1,2-c]pyrimidin-5,7(1H, 6H)-dione (8) in 38 and 48% yield, respectively. Treatment of 6 with 3N aqueous NaOH at room temperature gives 3,3-dimethyl-imidazo[1,2-c]pyrimidin-2,5,7 (1H, 3H, 6H)-trione (9) in 51% yield (Scheme 3).  相似文献   

20.
Synthesis of Evernin Two syntheses of the depside evernin 6 are described. Condensation of methyl acetoacetate and methyl crotonate followed by aromatization and reduction with Raney-Ni led to methyl orsellinate (3) . The condensation of everninic acid (4) , obtained by partial methylation of 3 and saponification of the methyl ester, with methyl 2, 4-dihydroxy-3, 6-dimethylbenzoate (methyl β-orcin carboxylate) (5) in presence of cyclohexylcarbodiimide gave evernin ( 6 ). In a second syntheis methyl dihydroorsellinate (1) was regiospecifically converted into its 4-methyl enol ether and aromatized via the benzene selenenyl derivative to yield methyl evernate (7) . Benzylation followed by saponification gave the free acid 8 . Methyl β-orcin carboxylate (5) was synthesized in an analogous way from methyl 3,6-dimethyl-2,4-dioxocyclohexanecarboxylate. Condensation of 8 with the methyl ester 5 by treatment with trifluoroacetic anhydride in toluene yielded 9 , which could be converted into evernin ( 6 ) by hydrogenolysis of the benzyl ether.  相似文献   

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