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Addition of chlorine to methyl 3-(dichloromethyl)-4,4-dichlorocrotonate (1), a critical procedure in the total synthesis of the title compound MX, was modified by using novel catalysts. A minor modification in the purification of MX was also described. 相似文献
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QIAO Yu-Qin Lü Xing-Qiang BAO Feng KANG Bei-Sheng② 《结构化学》2005,24(8):957-961
1 INTRODUCTION In contrast to the old-line academic and practical studies of 1-phenyl-3-methyl-4-benzoyl-5-pyrazo- lone (PMBP) on the metal coordination chemistry[1], the complexes of β-ketoamines derivated from PMBP received little attention due to its complicated com- plexation. However, in recent years, there has a sudden growth of this area as a result of its timely interest in biological activities[2]. Recently, a series of β-ketoamines[3] containing PMBP have been prepared fro… 相似文献
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Coupling of trimethylsilyl derivative of methyl 1,2,4-triazole-3-carboxylate with 2--(chloromethyl)-1,3-di--benzyl glycerol, followed by amination and removal of the protecting groups afforded 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl]-1,2,4-triazole 3- and 5-carboxamides, 1a and 1b, respectively. 相似文献
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Z. I. Tyukhteneva L. A. Badovskaya I. N. Kozlovskaya G. F. Muzychenko 《Chemistry of Heterocyclic Compounds》1985,21(12):1339-1342
Aminolysis of 2(5H)-furanone leads to 3-alkylamino-4-hydroxy-N-alkylbutyramides which easily form hydroxy derivatives of thiourea. The latter, depending on the protonation or quaternization site, easily undergo cyclization to thiazolidine and oxazolidine derivatives.Translated from Khimiya Geterotsiklicheskilch Soedinenii No. 12, pp. 1629–1632, December, 1985. 相似文献
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A practical and improved synthesis of (3S,5S)-3-[(tert-butyloxycarbonyl)methyl]-5-[(methanesulfonyloxy)methyl]-2-pyrrolidinone (1) is described. The key transformations involve a highly efficient reaction sequence consisting of ethoxycarbonylation, alkylation, hydrolysis, and decarboxylation to produce compound 10. The process described herein is practical, robust, and cost-effective, and it has been successfully implemented in a pilot plant to produce a multikilogram quantity of mesylate 1. 相似文献
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4-羟基-2,5-二甲基-3(2H)呋喃酮的合成 总被引:3,自引:0,他引:3
总结了食品增香剂4-羟基-2.5-二甲基-3(2H)呋喃国的合成方法,包括近期的合成研究进展,对一些合成方法的优缺点作了评述。参考文献28篇。 相似文献
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Brominated analogues (BMXs) of the strong drinking water mutagen MX (3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone) were found to be subject to strong matrix induced chromatographic response enhancement effects. We evaluated different ways to reduce errors in quantification including comparison of gas chromatographic inlet systems, improved clean up of sample extracts, and preparation of calibration standards in the sample matrix. The best quantitative accuracy and long term performance were achieved when the calibration standards were prepared in sample matrix, samples were cleaned up with C18-resin in conjunction with solid phase extraction (SPE) with Oasis HLB cartridges, and gas chromatography with PTV splitless injection was used. This method enables the determination of MX and BMXs from 500 ml water sample with quantitation limits of 1 ng/l or less. 相似文献
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A method for the determination of 3-chloro-4-(dichloromethyl)-5-hydroxy-2[5H]-furanone (MX), in drinking water by GC-MS with a limit of detection of 3.0 microg/l and a limit of quantification of 7.0 microg/l is presented. Clean-up by SPE and extraction of water samples with dichloromethane were carried out before the preconcentration of MX, which was derivatized directly in the injector of the GC, and the MX trimethylsilyl derivative was identified and quantitatively determined by MS. 相似文献
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F. A. Gimalova G. M. Khalikova V. A. Egorov A. G. Mustafin M. S. Miftakhov 《Russian Chemical Bulletin》2013,62(5):1227-1231
Methyl (2E,4S,5S)-5-hydroxy-6-mesyloxy-2-methyl-4-(pent-3-yloxy)hex-2-enoate was synthesized from l-tartaric acid. Attempted substitution of the mesyloxy group by the reaction with NaN3 directly led to methyl (E)-2-[(3S,4S)-4-hydroxy-3-(pent-3-yloxy)pyrrolidin-2-ylidene]propanoate. The latter on treatment with CF3COOH and then NaOH gave methyl (2E)-2-methyl-4-[(S)-oxiran-2-yl]-4-(pent-3-yloxy)but-2-enoate. 相似文献
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Polezhaeva N. A. Volodina Yu. M. Kalinina I. V. Sahibullina V. G. Chmutova G. A. Galkin V. I. Cherkasov R. A. 《Russian Journal of General Chemistry》2002,72(8):1202-1206
The reaction of 3,4-dichloro-5-hydroxy-2(5H)-furanone with 2 mol of tributylphosphine involves substitution of both chlorine atoms to form an unstable diphosphonium salt. The latter undergoes partial hydrolysis with cleavage of one of the P-C bonds, yielding finally a monophosphorylation product. A probable reaction pathway is considered in terms of quantum chemistry. 相似文献