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1.
Base decomposition of 4‐(substituted phenyl)‐1,2,3‐selenadiazoles at room temperature resulted in 2‐(substituted phenyl)‐ethynylselenolate anions, which were immediately reacted with bromoacetonitrile to give a series of 2‐(substituted phenyl)ethynylselanylacetonitriles.  相似文献   

2.
A new synthesis of 4,4-dialkyl-2-(substituted)phenylsemicarbazides has been developed. The procedure begins with a 5-substituted-3-(substituted)phenyl-1,3,4-oxadiazolin-2(3H)-one, 3 , which is treated with dialkylamine to give a 1-acyl-4,4-dialkyl-2-(substituted)phenylsemicarbazide, 7 . Subsequent base-catalyzed hydrolysis of 7 gives 4,4-dialkyl-2-(substituted)phenylsemicarbazides, 14 , in high yield. With a variety of nucleophilic reagents, the compounds 3 also undergo ring opening.  相似文献   

3.
The oxidative addition of dimethyl malonate to ring substituted styrenes leads to the formation of substituted dimethyl (2-oxo-2-phenylethyl) malonate and methyl 2-oxo-5-phenyltetrahydrofuran-3-carboxylate along with small amounts of substituted dimethyl [2-(nitrooxy)-2-phenylethyl] malonate and dimethyl 2-methoxy-2-phenylethyl) malonate. A tentative mechanism which supports the formation of these products is also presented.  相似文献   

4.
以2-氨基-5-取代苯氧甲基-1,3,4-噻二唑(1)为起始原料, 合成了中间体2-氯乙酰氨基-5-取代苯氧甲基-1,3,4-噻二唑)-2-乙酰亚胺(2)和2-(5-取代苯氧甲基-1,3,4-噻二唑-2-亚胺基)-4-噻唑啉酮(3), 化合物3进一步与取代苯甲醛发生类Knoevenagle缩合反应, 得到了一系列2-(5-取代苯氧甲基-1,3,4-噻二唑-2-亚胺基)-5-(取代苯基亚甲基)-4-噻唑啉酮类化合物4a4p. 目标化合物4a4p的结构经IR, 1H NMR和元素分析确证.  相似文献   

5.
The mass spectra of several benzoyl hetarenes, of 2-benzoyl pyridines substituted at the phenyl and pyridyl group, respectively, and of phenyl substituted 2-benzoyl pyrroles, have been studied with respect to the formation of benzoyl and hetaroyl ions. A correlation between the intensity of benzoyl ions, relative to molecular ion intensity, and the π-electron density at the substituted carbon atom of the hetarene has been observed for benzoyl hetarenes. The relative intensities of (substituted) benzoyl ions of substituted 2-benzoyl pyridines and 2-benzoyl pyrroles are not easily related to substituent constants of Hammett equations. The relative ionization energies of phenyl substituted 2-benzoyl pyridines, however, and the relative appearance energies of substituted benzoyl ions derived therefrom follow the σIP+-constant of Bentley and Johnstone and the σ+-constants of Brown, respectively.  相似文献   

6.
徐莉  徐世平  徐嵩  李兰敏 《有机化学》2000,20(5):827-829
报道了由吲哚-2-甲醛和取代苯胺进行亲核加成反应合成了22个2-(取代苯亚氨次甲基)吲哚衍生物,主要对本类化合物的两种质谱特殊裂解过程进行了分析研究。  相似文献   

7.
β-三氯锗取代丙酰氯1a~1c与(R)TTCA酯反应, 得到光学活性的(R)-N-(β-三氯锗取代丙酰基)TTCA酯3a~3d([α]D^2^0-86.00~-94.35ⅲ)及光学活性的β-三氯锗取代丙酰氯2a~2d。化合物3a~3d经水解得到(R)-N-(β-取代丙酰基)TTCA酯基锗倍半氧化物4a~4d, [α]D^2^0-44.48~-77.00ⅲ。用半经验量子化学MNDO方法研究了反应物和产物最优构型的电子结构及反应的焓变。  相似文献   

8.
A Pd-catalyzed orthogonal synthesis of substituted 2-hydroxybenzoates and substituted cyclohexanones was developed for the first time. The substituted 2-hydroxybenzoates were obtained from acyclic unsaturated 1,3-carbonyl compounds using a combination of catalytic Pd(OAc)2 and Cu(OAc)2. On the other hand, the substituted cyclohexanones were produced from similar substrates via catalytic Pd(OAc)2 and hydrogen chloride. Each transformation was clean, easy to work up, provided the desired compounds in good purities, and did not require column chromatography purification.  相似文献   

9.
通过2-氨基-5-巯基-1,3,4-噻二唑与取代苯甲酰基异氰酸酯及取代苯氧乙酰基异氰酸酯反应,合成了21种新的取代苯甲酰基脲与取代苯氧乙酰基脲,其结构用红外光谱、核磁共振氢谱和元素分析进行了确证,初步的生物活性测定试验表明,部分目标化合物具有良好的植物生长调节活性.  相似文献   

10.
A new series of 3‐substituted‐thiazolyl‐2‐iminothiazolidin‐4‐ones were synthesized by nucleophilic substitution of p‐substituted‐thiazol‐2‐yl‐chloroacetamides with potassium thiocyanide by cyclization. The starting material p‐substituted‐thiazol‐2‐yl‐chloroacetamides were synthesized from p‐substituted‐thiazol‐2‐yl‐amines with chloroacetyl chloride, which in turn was prepared from one pot reaction of substituted aryl acetophenone and amino group of thiourea. The title compounds were investigated for their anticonvulsant activity. Among the tested compounds, compound 3‐(4‐(4‐fluorophenyl)thiazol‐2‐yl)‐2‐iminothiazolidin‐4‐one ( 16 ) emerged as the most active compound of the series, and it is moderately more potent than the reference standard diazepam.  相似文献   

11.
邻氮基苯甲酸;缩合反应;卤代-2-(3-甲基-5-取代-4H-1;2;4-三唑-4-基)-苯甲酸的合成  相似文献   

12.
The thioamide vinylogues (2-aminovinyl thioketones) react as heterodienes with open-chain and cyclic dienophiles to give substituted 4-amino-3,4-dihydro-2H-thiopyrans, or substituted 2H-thiopyrans and substituted 7 - methyl - 7,7a - dihydro - 5H - thiopyranno[2,3 - c] - 5 - furanones respectively, in good agreement with calculated perturbation energy of second order.  相似文献   

13.
2‐Ethoxy carbonylcyclopentanone (1) has been brominated to yield 2‐bromo‐2‐ethoxy carbonylcyclopentanone (2) which on further reaction with substituted thiosemicarbazones, thiocarbohydrazones, thiocarbamides and carbamides has furnished 1 ‐ thia‐3,4‐diaza‐5,7‐dioxo‐2‐[(substituted benzylidine)‐amino]spiro[4.5]dec‐2‐ene (3a–e) , 1‐thia‐3,4‐diaza‐5,7‐dioxo‐2‐[(substituted benzylidine)‐hydrazino] spiro[4.5]dec‐2‐ene (4a–e) , 1‐thia‐3‐aza‐2‐(substituted imino)‐4,6‐dioxo‐spiro[4.4]nonane (5a–f) and 1‐oxa‐3‐aza‐2‐(substituted imino)‐4,6‐dioxo‐spiro[4.4]nonane (6a–g) respectively. The structures of the compounds have been elucidated on the basis of spectral analysis.  相似文献   

14.
A general and regioselective synthesis of substituted pyrroles 2 by cycloisomerization of readily available (Z)-(2-en-4-ynyl)amines 1 is reported. Spontaneous cycloisomerization leading to 2 occurred in the course of preparation of enynamines bearing a terminal triple bond or a triple bond substituted with a phenyl or a CH2OTHP group. When the triple bond was substituted with an alkyl or alkenyl group, enynamines were stable and could be converted into the corresponding pyrroles by metal catalysis. CuCl2 was found to be an excellent catalyst for cycloisomerization of substrates substituted at C-3, while PdX2 in conjunction with KX (X = Cl, I) turned out to be a superior catalyst for the reaction of enynamines unsubstituted at C-3.  相似文献   

15.
Reaction of pyridine and substituted pyridines with N2O5 in an organic solvent gives the N‐nitropyridinium ion. When this is reacted with SO2/HSO3‐ in water, 3‐nitropyridine is obtained (77 % yield). With substituted pyridines the method gives good yields for 4‐substituted and moderate yields for 3‐substituted pyridines. The reaction mechanism is not an electrophilic aromatic substitution but one in which the nitro group migrates from the 1‐position to the 3‐position by a [1,5] sigmatropic shift. From 3‐nitropyridine, 5‐nitropyridine‐2‐sulfonic acid is formed in a two step reaction. From this, a series of 2‐substituted‐5‐nitropyridines has been synthesized. 3‐Nitropyridine and 4‐substituted‐3‐nitropyridines have been substituted with ammonia and amines by the vicarious nucleophilic substitution (VNS) method with ammonia and amines and by the oxidative substitution method in the position para to the nitro group. High regioselectivities and yields have been obtained in both cases to afford a series of 4‐substituted‐2‐alkylamino‐5‐nitropyridines. The VNS method has also been used in alkylation reactions with 3‐nitropyridines to form dichloromethyl‐and alkoxycarbomethyl‐β‐nitropyridines. From the appropriate substituted nitropyridines imidazopyridines and azaindoles have been formed.  相似文献   

16.
应用AM1方法研究了氰基丙二烯和乙烯环加成反应的反应机理,讨论了氰基对反应机理的影响。结果表明乙烯和氰基丙二烯之间的反应是自由基反应,乙烯进攻氰基丙二烯的中心碳原子从能量上考虑比进攻两端碳原子更为有利,且位垒比丙二烯上无取代基时低,比氨基取代时高,说明吸电子基团氰基取代氢原子后,使环加成反应易于进行,但没有供电子基团氨基的作用大。以上结论均与实验结果一致。  相似文献   

17.
A convenient synthetic procedure for substituted 2-bromomethyl-4-methyl-2-chloro-2,3-dihydrofuro[3.2-c]quinolines hydrobromides was developed, synthons for preparation of new substituted furoquinolines. Reactions with various nucleophiles were performed, and 2-(R’-methyl)-4-methyl-furo[3.2-c]quinolines substituted in the benzene ring were obtained.  相似文献   

18.
Barbier allylation and Friedel-Crafts alkylation of (un)substituted benzaldehydes, allylbromide and phenols can be combined in a one-pot process in ionic liquid (BuPyC1/SnC12·2H2O) to directly synthesize 4-(2-hydroxyphenyl)- 4-[(un)substituted phenyl]but-1-ene compounds, which were applied to the synthesis of 4-(substituted phenyl)- chromans through intramolecular cyclization reactions.  相似文献   

19.
陈寿山  姚文庆 《化学学报》1990,48(3):262-265
本文报道了取代环戊二烯基负离子与[(η^5-C5H5)TiCl2]2O反应生成(η^5-C5H5)(η^5-C5H4R).TiCl2的新方法. 研究了取代环戊二烯基负离子的空间位阻和(η^5-C5H5)TiCl3, [(η^5-C5H5)TiCl2]2O的结构以及反应温度对产物产率的影响. 合成了七个新的(η^5-C5H5)(η^5C5H4R)TiCl2类型的化合物及七个相应的二氟化合物。  相似文献   

20.
l-Benzoxepino(3, 4-b)quinolin-l3(6H)-one and its halogen,alkyl, alkoxy derivatives Va'-d' and 1-benzothiepino(3,4-b}-quinolin- 13 ( 6H)-one Vf, and its alkyl derivatives Vg, weresynthesized through cyclization of 2-(substituted phenoxymethyl)-3-quinolinecarboxylic acids Va-d and 2-[ (un)substituted phen-ylthiomethyll-3-quinolinecarboxylic acids IVf-g in the presence ofpolyphosphoric acid.The acids IV were obtained from the corresponding ethyl-esters @ whcih were prepared through refluxing ethyl 2-bromo-methyl-3-quinolinecarboxylate(1) with substituted phenol or (un)substituted thiophenol in the presence of NaOEt.The compound Vg, was allowed to react with NBS, KaBH4, NH2OH-HCl to give compounds VII , VIII, and IX, respectively.The structures of 24 new compounds have been confirmed by elemental analysis, IR and 1H NMR.  相似文献   

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