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以1,3-二甲基脲和氰乙酸为原料,通过脱水缩合反应、合环、亚硝化和还原得到1,3-二甲基-5,6-二氨基脲嘧啶。通过熔点测定表征了化合物,反应收率95.2%,同时对各步反应的影响因素进行了探讨。该方法操作简单、成本低,适于工业化大生产。 相似文献
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合成了2,6-二甲基-3,5-二乙氧羰基-1,4-二氢吡啶,并研究了它在紫外光(366nm)照射下的光化学反应。结果表明,主要的光化产物为2,6-二甲基-3,5-二乙氧羰基吡啶(占95%)其次是少量的二-π甲烷光重排产物,1,3-二甲基-2-氮杂-4,5-二乙氧羰基-双环-[3、1、0]-己烯-3(占5%)。 相似文献
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在琥珀酸二酰亚胺磺酸铈催化下,吲哚、醛和2,2-二甲基-1,3-二噁烷-4,6-二酮在无溶剂条件下超声辐射合成了10种5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物.当催化剂的用量为3%(摩尔分数)时,30℃反应30~60 min,收率为68.9%~96.7%.此外,还探讨了琥珀酸二酰亚胺磺酸铈的催化机理.该方法具有条件温和,反应时间短且收率高的优点.催化剂邻琥珀酸二酰亚胺磺酸铈对环境友好且可循环利用. 相似文献
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隣氨基苯甲酸与N-(β-二乙氨基-乙基)-甲酰胺或N-(δ-二乙氨基-α-甲基-正丁基)甲酰胺缩合,分别形成3-(β-二乙氨基-乙基)3,4-二氢化杂二氮[1,3]萘-酮-[4]与3-(δ-二乙氨基-α-甲基-正丁基)3,4-二氢化杂二氮[1,3]萘-酮-[4]。 5-氯代-隣位氨基苯甲酸舆N-(β-二乙氨基-乙基)-甲酰胺或N-(δ-二乙氨基-α-甲基-正丁基)-甲酰胺缩合,分别形成6-氯代-3-β-二乙氨基-乙基-3,4-二氢化杂二氮[1,3]-萘酮-[4]及6-氯代-3-(δ-二乙氨基-α-甲基-正丁基)-3,4-二氢化杂二氮[1,3]萘酮-[4]。 相似文献
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无外加催化剂条件下芳香醛与活性亚甲基化合物的缩合反应和迈克尔加成反应 总被引:2,自引:1,他引:2
在DMF溶剂中,不外加催化剂使芳香醛(1)与2,2-二甲基-1,3-二氧六环-4,6-二酮(2)发生缩合反应生成2,2-二甲基-5-芳亚甲基-1,3-二氧六环-4,6-二酮(3a~f)。在同样条件下,芳香醛与5,5-二甲基-1,3-环己二酮(4)则发生缩合和迈克尔加成反应生成2,2'-芳亚甲基双(3-羟基5,5-二甲基-2-环己烯-1-酮)(5a~h)。用单晶X-射线分析法确定了产物5b的晶体结构。 相似文献
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Akbalina Z. F. Abushakhmina G. M. Kabal'nova N. N. Zlotskii S. S. Shereshovets V. V. 《Russian Journal of General Chemistry》2002,72(9):1406-1409
The kinetic regularities of the reactions of dimethyldioxirane with 1,3-dioxane, 2-propyl-, 2-isopropyl-, 2-phenyl-, 2,2-pentamethylene-, 2,2-dimethyl-, and 4-(hydroxymethyl)-2,2-dimethyl-1,3-dioxolanes, as well as with 2-isopropyl-, 2-phenyl-, 2,2,4-trimethyl-, 2-isopropyl-4-methyl-, 4-methyl-, 4-methyl-2-phenyl-, and 5,5-dimethyl-2-phenyl-1,3-dioxanes in acetone were studied by spectrophotometry. The reaction kinetics are described by a second-order equation (first order in dioxirane and first order in dioxacycloalkane). The reaction rate is independent of the concentration of oxygen in the reaction mixture. The activation parameters of the reactions were determined. 相似文献
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T. S. Khlebnikova V. G. Isakova F. A. Lakhvich 《Russian Journal of General Chemistry》2011,81(2):361-368
The reaction of 5,5-dimethyl-2-[(3-fluoro- and 4-fluoro)benzoyl]cyclohexane-1,3-diones with primary and secondary amines affords their exocyclic enamine derivatives. Under similar conditions 5,5-dimethyl-2-(2-fluorobenzoyl)]cyclohexane-1,3-dione undergoes dehydrofluorination and intramolecular cyclization to give 3,3-dimethyl-2,3,4,9-tetrahydro-1H-xanthene-1,9-dione. The reaction of vinylogous substitution of the enol derivatives of the fluorinated 5,5-dimethyl-2-benzoylcyclohexane-1,3-diones (vinylogous acyl chlorides) with amines results in the formation of the endocyclic enaminoderivatives. 相似文献
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Ts. Ye. Aghajanian G. L. Arutyunian R. K. Shahkhatuni 《Chemistry of Heterocyclic Compounds》2003,39(6):767-770
Alternative methods for the synthesis of 2-spiro-substituted 6-hydroxy-5,7-dimethyl-1,3-diazaadamantanes have been developed. These are the reduction of the ketone group to hydroxyl in the corresponding 6-oxo-1,3-diazaadamantanes and the condensation of 9-hydroxy-1,5-dimethyl-3,7-diazabicyclo[3.3.1]nonane (obtained by different routes from 5,7-dimethyl-6-oxo-1,3-diazaadamantane) in reaction with cyclic ketones. 相似文献
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An indirect spectrophotometric method, based on the rapid Diels-Alder reaction between cisoid 1,3-dienes and tetracyanoethylene (TCNE) and the destruction of an aromatic-TCNE pi-complex, was developed to determine eleven 1,3-dienes in the 0.05-1.00 x 10(-3)M range. These dienes were: cyclopentadiene; 1,3-cyclohexadiene; trans-1,3-pentadiene; 2,4-dimethyl-1,3-pentadiene; trans-2-methyl-1,3-pentadiene; 2-methyl-1,3-butadiene; 9-methylanthracene; 9,10-dimethylanthracene; 1,6-diphenyl-1,3,5-hexatriene; 2,3-dimethyl-1,3-butadiene; and 1,4-diphenyl-1,3-butadiene. Three 1,3-dienes were determined in the 0.05-1 x 10(-4)M range: cyclopentadiene, trans-2-methyl-1,3-pentadiene, and anthracene. The limit of detection for cyclopentadiene in carbon tetrachloride solutions is 0.11 microg/ml. Fourteen 1,3-dienes were found to form stable pi-complexes and could not be determined by the proposed method. For these 1,3-dienes, the spectra of some of the complexes are reported; in addition, relative equilibrium constants for the pi-complexes of 2,5-dimethyl-2,4-hexadiene, cis-1,3-pentadiene, 4-methyl-1,3-pentadiene, and 1,3-cyclo-octadiene were estimated. An explanation of the transient colour in the 1,3-diene-TCNE Diels-Alder reaction is suggested. 相似文献
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Fumio Yoneda Ryosuke Koga Sadao Nishigaki Shinobu Fukazawa 《Journal of heterocyclic chemistry》1982,19(4):949-951
Treatment of 6-amino-1,3-dimethyl-5-nitrosouracil (Ia) with dimethyl acetylenedicarboxylate (DMAD) in dimethylformamide (DMF) afforded 6,7-bis(dimethoxycarbonyl)-1,3-dimethyllumazine (II). Similarly, the reaction of 6-amino-1,3-dimethyl-5-phenylazouracil with DMAD gave also II. Hydrolysis of II with hydrochloric acid gave 1,3-dimethyllumazine-6-carboxylic acid (III). III was chlorinated with thionyl chloride and then aminated with ethanolic ammonia to give rise to 6-carbamoyl-1,3-dimethyllumazine (V). V was alternatively synthesized by the treatment of Ia with propiolamide in DMF. 相似文献
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A variety of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones 5a-l and the corresponding 6-substituted 4-hydroxy-2-pyrones 3a-l were prepared in high yields under mild reaction conditions by the reaction of 2,2,6-trimethyl-1,3-dioxin-4-one 4 with 1-acylbenzotriazoles 9 in the presence of LDA followed by thermal cyclization of 5a-l to 3a-l. Synthesis of novel 6-(1-benzoylalkyl)-2,2-dimethyl-1,3-dioxin-4-ones 12a-c was achieved by alkylation of dioxinone 5a and their subsequent cyclization gave 5-alkyl-4-hydroxy-2-pyrones 13a-c. 相似文献
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T. D. Sokolova K. I. Romanova Yu. F. Malina B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1975,11(12):1391-1394
The corresponding stereoisomeric p-nitrobenzoates were obtained by reaction of the geometrical isomers of 1,3-dimethyl-, 1,2,5-trimethyl-, and 1-tert-butyl-3-methyl-4-hydroxypiperidines with p-nitrobenzoyl chloride. The stereoisomers of the corresponding benzoates were also synthesized from the geometrical isomers of 1,3-dimethyl-4-hydroxypiperidines. The primary conformations of the investigated compounds in solution were established by means of their PMR spectra. 相似文献