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1.
5-Nitropentan-2-one reacts with methylamine and formaldehyde according to the Mannich reaction pattern to give 5-hexahydropyrimidinylcarbonyl-substituted 1-nitro-3,7-diazabicyclo[3.3.1]nonane in one experimental stage. When methyl 3-R-4-nitrobutanoates are used, the reaction stops after the formation of substituted 5-nitrohexahydropyrimidines in 40–98% yields. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1687–1693, July, 2005.  相似文献   

2.
Reaction of acetylacetone and ethyl acetoacetate with 1-(ω-bromoalkyl)-3,6-dimethyluracyls and 1,3-bis(ω-bromoalkyl)-6-methyluracyls lead to the formation of uracyl derivatives containing the ketone and ketoester fragments. Conditions leading to the highest yields of the compounds synthesized were found.  相似文献   

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Mixtures of products of the reaction of dibenzoylfuroxane with isopropylamine, tert-butylamine, and methylhydrazine were separated by high-pressure liquid chromatography. According to the proposed reaction scheme, benzamidoglyoxime is formed in the first step, after which it undergoes cyclization to give an N-substituted 3-amino-4-nitroso-5-phenylisoxazole or decomposes via the mechanism of a Beckmann rearrangement of the second type.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 616–619, May, 1978.  相似文献   

6.
2,5-Substituted 3,3,4,4-tetracyanopyrrolidines react with primary alcohols in the presence of an excess of a base or with the base itself. 2-(N-Arylideneamino)-5-alkoxy-3,4-dicyanopyrroles are formed as a result of the reactions with alcohols, and 2,5-diamino-1-R-3,4-dicyanopyrroles are formed as the result of the reaction with primary aliphatic amines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1502–1507, November, 1991.  相似文献   

7.
Conclusions The direction of the reaction of the silicon hydrides: R2SiH2, RSiH3, and with primary aliphatic amines, in the presence of catalysts based on Group VIII compounds, as a function of the structure of the silicon hydride and the nature of the employed catalyst, was established.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2330–2333, October, 1972.  相似文献   

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Three-component condensation of 2-aminobenzimidazole and its N-substituted derivatives with formaldehyde and primary amines gave 1,2,3,4-tetrahydro[1,3,5]triazino[1,2-a]benzimidazoles. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 355–356, February, 2007.  相似文献   

10.
乙酰乙酸乙酯分光光度法测定甲醛的研究   总被引:5,自引:0,他引:5  
乙酰乙酸乙酯在弱酸性溶液中与甲醛及铵离子反应,生成2,6-二甲基-1,4-二氢-3,5-吡啶二乙酸乙酯,该化合物在375nm处有最大吸收,以甲醛计的摩尔吸光系数为5.533×103mol·cm-1·L-1;利用该反应建立了测定食品中微量甲醛的新方法,甲醛质量浓度在0.08~4.0mg/L成线性关系。并用质谱分析了产物,证实在水溶液中该反应遵循汉秋希吡啶合成法的原理。  相似文献   

11.
One-pot reactions of dimethyl sulfonyldiacetate and N-methyl-2r,6c-di(methoxycarbonyl)-3t,5t-diphenyltetrahydro-1,4-thiazine 1,1-dioxide with formaldehyde and primary amines lead to derivatives of 9-thia-3,7-diazabicyclo[3.3.1]nonane 9,9-dioxide resulted from decarboxylation of the ester groups at the positions 1 and 5. The effects of the reaction conditions and structure of the starting reagents on the yields of 9-thia-3,7-diazabicyclo[3.3.1]nonane 9,9-dioxides were studied.  相似文献   

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Conclusions Starting with 1,4-dibromo-1,2-butadiene we synthesized bis(1-bromo-1,2-butadienyl)-N-(-hydroxyethyl)amine, which was reacted with primary amines to give 2,6-diethynyl-1-N-alkyl-4-N-(-hydroxyethyl)piperazines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2579–2582, November, 1975.  相似文献   

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The alkylation reactions of the ambident ethyl acetoacetate anion with C2H5X (X = F, Cl, Br, and I) in the O2, C3, and O4 positions of the anion were investigated at the B3LYP/6-311+G(d,p) level of theory. It was found that the ethylation reaction does not occur in the position O4, as well as with ethyl fluoride in any position of the anion, due to very high activation energies and thermodynamic instability of the hypothetic products. The activation energies for the reactions in the position O2 are lower in comparison to the position C3, but the products of the reactions in the C3 position are more stable than those in the position O4, implying that the C/O products ratio is controlled by both thermodynamic and kinetic factors, leading to the O2-product with the chloride, and C3-product with the iodide as leaving group.  相似文献   

16.
2-芳基乙酸及乙酸酯具有显著的生物生理活性[1],是合成异黄酮[2]、异喹啉[3]衍生物的重要原料.苯乙腈水解法、苯乙酰胺水解法都曾用于芳基乙酸的合成[4].二羰基化合物的直接芳基化是合成该类化合物的最直接有效的方法.这些方法一般需要过渡金属催化剂的催化和配体的参与[5].  相似文献   

17.
Conclusions The electrochemical chlorination of ethyl acetoacetate in aqueous media proceeds at C2 and, partially, at C4 to give ethyl 2,2-dichloroacetoacetate and small amounts of ethyl 2,2,4-trichloroacetoacetate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 876–877, April, 1988.  相似文献   

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The reaction of 2-hydrazinobenzothiazole (1) with ethyl acetoacetate has twice been reported to yield a fused triazepinobenzothiazolone, namely, 3-methyl[1,2,4]triazepino[3,4-b]benzothiazol-5(4H)-one (4). We have repeated this work and reassigned the reaction product as 2-(2-benzothiazolyl)-1,2-dihydro-5-methyl-3H-pyrazol-3-one (5) on the basis of X-ray crystallography.  相似文献   

20.
The transesterification of ethyl acetoacetate (EtOAcac) without the use of catalysts is shown for primary, secondary and tertiary alcohols. The use of molecular sieves, which are used to shift the equilibrium, allows the synthesis of products in high yields and acceptable reaction times, which are on a par with those for transesterification processes using catalysts. The kinetics of the transesterification of EtOAcac with tert-amyl alcohol is studied.  相似文献   

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