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1.
Xian-Gui HuangJia Liu Jiangmeng RenTao Wang Weidong ChenBu-Bing Zeng 《Tetrahedron》2011,67(34):6202-6205
A simple and efficient procedure was developed for the synthesis of multisubstituted 2-aminothiophene derivatives. In the presence of catalytic amount of imidazole, ketones or aldehydes, dicyanomethane and elemental sulfur were converted into the corresponding 2-aminothiophene derivatives in moderate to high yields in DMF at 60 °C. 相似文献
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An efficient method for the synthesis of novel pyrido[3',2':4',5']thieno[3',2':2,3]pyrido [4,5:d][1,3]thiazolo[3,2-a]pyrimidine-4-one derivatives (5) has been developed using a Pictet-Spengler reaction between 2-(3-aminothieno[2,3-b]pyridin-2-yl)thiazolo[3,2-a] pyrimidin-5-one (3), which could be obtained from the condensation of 7-(chloromethyl)-5H-thiazolo[3,2-a]pyrimidin-5-one (1) with 3-cyanopyridine-2-thione (2) via Thorpe-Ziegler isomerization, and aromatic aldehydes under NH2SO3H as catalysis in good yields. 相似文献
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A convenient one-pot three-component method for the preparation of tetra-substituted thiophene derivatives has been developed. Reaction of acetyl acetone 1, phenyl isothiocynate 2 and 2-chloromethyl derivatives 3a–3c in the presence of potassium carbonate afforded the target compounds, namely ethyl2-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-2-oxoacetate derivatives 4a–4e, ethyl 3-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-3-oxopropanoate derivatives 4f–4i, di((4-acetyl-3-methyl-5-phenylamino)thiophen-2-yl)ketone derivatives 4j–4n in reasonable overall yields. The synthesized compounds were screened for antimicrobial activity. The detailed synthesis, spectroscopic data and antimicrobial activities of synthesized compounds were reported. 相似文献
5.
Sajjad Salahia Malek Taher Maghsoodloua Nourallah Hazeria Mojtaba Lashkaria Santiago Garcia-Granda Laura Torre-Fernandez 《催化学报》2015,(7):1023-1028
The one-pot eight-component reaction between Meldrum's acid, an aromatic aldehyde, and an aryl amine was achieved in the presence of citric acid catalyst. The corresponding dispirohydroquino-lines were obtained in good yields with excellent diastereoselectivity. This method is a combination of the Knoevenagel and Michael reactions. 相似文献
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A mild and efficient one pot method for the synthesis of indolo[3,2-a]carbazole derivatives by the para-toluenesulfonic acid catalyzed condensation of indole with acyclic 1,2-diones is described. With cyclobutene-1,2-diones the reaction afforded indole substituted carbazole derivatives in good yield. 相似文献
8.
Yana Yu. Shmoylova Yuri A. Kovygin Irina V. Ledenyova Mikhail A. Prezent Elena D. Daeva Sergey V. Baranin Khidmet S. Shikhaliev 《Mendeleev Communications》2021,31(2):259-261
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9.
Ramadan Ahmed Mekheimer Mohamed Abdallah Ameen Kamal Usef Sadek 《中国化学快报》2008,19(7):788-790
Green conditions have been developed for the synthesis of substituted 2-aminothiophenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal energy. 相似文献
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An efficient and straightforward synthesis of furo[3,2-c]coumarins via the one-pot three-component condensation of aromatic aldehydes, 4-hydroxycoumarin and α-chloroketones in refluxing n-propanol is described. Pyridine or a mixture of AcOH and AcONH4 was used as a basic catalyst. 相似文献
11.
Green conditions have been developed for the synthesis of substituted 2-aminothiopbenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal energy. 相似文献
12.
The reduction of 4-chloro-3,5-dinitrobenzonitrile via catalytic hydrogenation and/or titanium trichloride produced three successive hydroxylamines 6,7 , and 8 that were fully characterized during complete reduction to the diamine 9. The nitrohydroxylamine 6 was acetylated to the mono-N-acetyl and bis-acetyl derivatives 10 and 11 which reacted with pyridine to afford the pyrido[1,2-a]benzimidazole 13 . An analoguous series of reactions was executed with 4-chloro-3,5-dinitrobenzotrifluoride to afford the pyrido[1,2-a]benzimidazole 21 . Structure confirmation of 21 was established via an x-ray determination. The mechanism of the transformation is discussed. 相似文献
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Abbas Ali Esmaeili Mahdieh Zangouei Ali Reza Fakhari Azizollah Habibi 《Tetrahedron letters》2012,53(11):1351-1353
We present a novel, convenient, and efficient method for synthesizing polysubstituted 3-oxo-2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyrimidines via a three-component reaction. The zwitterions generated from the reaction of isocyanides and dialkyl acetylenedicarboxylates react with 2-imino-1,3-thiazolidin-4-one to produce the title compounds in good yields. 相似文献
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A new synthetic procedure for the polysubstituted 2-aminothiophenes was developed via Gewald type ring-opening reaction of 1,1-dicyano-2,3-diarylcyclopropanes with elemental sulfur in N,N-dimethylformamide in the presence of morpholine as base. 相似文献
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A novel route for the synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2-ones from acetylated 2aminothiazoles and 2-aminopyridines under Vilsmeier conditions has been developed.The plausible mechanism has also been proposed. 相似文献
16.
Pradeep N.D. Singh 《Tetrahedron letters》2005,46(24):4213-4217
A simple and efficient method for synthesizing pyrrolines and tetrahydropyridines via an intramolecular aza-Wittig reaction has been achieved by microwave irradiation of the corresponding chloro-alkane derivatives in the presence of tertiary phosphite and sodium azide. The in situ formation of the alkyl azides makes this a facile and safe method for aza-Wittig reactions. 相似文献
17.
Several pyrrolo- and pyrido[1,2-a]indoles were prepared via an intramolecular Wittig reaction in good yields. This reaction sequence represents a facile entry into the mitosene ring system. 相似文献
18.
The methods for the synthesis of oxazolo[3,2-a]pyridinium and oxazolo[3,2-a]pyrimidinium salts and their reactivities are reviewed. Both systems exhibit ambident properties in reactions with nucleophiles;
depending on the substituents and the reagents, both the oxazole and azine rings can undergo opening and transformations.
A number of new methodologies involving oxazolopyridinium and oxazolopyrimidinium salts for the design of functionalized oxazoles,
imidazoles, fused pyrroles, and other heterocyclic systems are generalized.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 831–848, April, 2008. 相似文献
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The synthesis of pyrano[3,2-a]acridines is presented, where 7-chloro-9-phenyl-2,3-dihydroacridin-4(1H)-one reacts with arylaldehydes and malononitrile in the presence of piperidine in ethanol, giving with high yield via a multicomponent method. Also a new synthesis of pyrazolo[4,3-a]acridines is reported, where 7-chloro-9-aryl-2,3-dihydroacridin-4(1H)-one on Claisen condensation with ethylformate followed by hydrazine hydrate treatment through the intermediate 7-chloro-4-hydroxy-9-aryl-1,2-dihydroacridin-3-carbaldehyde. The structures of newly synthesized compounds were deduced by spectroscopic techniques, elemental analysis, and single-crystal x-ray diffraction. 相似文献