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1.
Anastasia A. Fesenko 《Tetrahedron》2009,65(11):2344-462
A general six-step approach to 6-tosyl-2,3,4,5-tetrahydro-1H-1,3-diazepin-2-ones has been developed. The key step involves a ring expansion reaction of 4-mesyloxymethyl- or 4-tosyloxymethyl-5-tosyl-1,2,3,4-tetrahydropyrimidin-2-one mediated by nucleophilic reagents. 相似文献
2.
Anastasia A. Fesenko 《Tetrahedron》2010,66(35):7219-462
A four-step method for the synthesis of 5-arylsulfonyl-substituted 1,2-dihydropyrimidin-2-ones has been developed. The reaction of readily available N-[(1-acetoxy-2,2,2-trichloro)ethyl]ureas with sodium enolates of α-arylsulfonylketones followed by heterocyclization-dehydration of the oxoalkylureas formed gave 5-arylsulfonyl-4-trichloromethyl-1,2,3,4-tetrahydropyrimidin-2-ones. The latter, in the presence of strong bases, eliminate CHCl3 to give the target compounds. 相似文献
3.
Anastasia A. Fesenko 《Tetrahedron》2010,66(4):940-462
A novel four-step methodology for the synthesis of 5-acyl-1,2-dihydropyrimidin-2-ones has been developed. The reaction of readily available N-[(1-acetoxy-2,2,2-trichloro)ethyl]ureas with Na-enolates of 1,3-diketones or β-oxoesters followed by heterocyclization-dehydration of the oxoalkylureas formed gave 5-acyl-4-trichloromethyl-1,2,3,4-tetrahydropyrimidin-2-ones. The latter, in the presence of NaH, eliminate CHCl3 to give the target compounds. 相似文献
4.
Ethyl 4-methyl-2-oxo-7-phenylthio-2,3,6,7-tetrahydro-1H-1,3-diazepine-5-carboxylate and/or ethyl 6-methyl-2-oxo-4-(phenylthiomethyl)-1,2,3,4-tetrahydropyrimidine-5-carboxylate were obtained in the reaction of ethyl 4-chloromethyl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate with PhSNa or PhSK with or without PhSH, depending on the reagent ratio, reaction time, or temperature, as a result of ring expansion and/or nucleophilic substitution. The reaction pathway was affected strongly by the basicity-nucleophilicity of the reaction media. The results obtained were confirmed by reactions of 4-mesyloxymethyl-6-methyl-5-tosyltetrahydropyrimidin-2-one with PhSNa/PhSH and ethyl 4-chloromethyl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate with NaCN/HCN or NaCH(COOEt)2/CH2(COOEt)2. 相似文献
5.
Dichlorobis(triphenylphosphine)palladium(II)/tricyclohexylphosphine-catalyzed Suzuki-Miyaura cross-coupling of the 2-aryl-6,8-dibromo-1,2,3,4-tetrahydroquinolin-4-ones with arylboronic acids afforded the corresponding 2,6,8-triaryl-1,2,3,4-tetrahydroquinolin-4-ones, exclusively. The latter was subjected to thallium(III) p-tolylsulfonate (TTS) in dimethoxyethane under reflux or to molecular iodine in methanol at reflux to afford the 2,6,8-triarylquinolin-4-(1H)-ones and 2,6,8-triaryl-4-methoxyquinoline derivatives, respectively. 相似文献
6.
Synthesis of 4-hydroxy-4-methyl-5-tosylhexahydropyrimidin-2-imines by reaction of N-cyano-N′-(1-tosylalk-1-yl)guanidines with enolates of tosylacetone was developed. Base-catalyzed dehydration of the obtained pyrimidines gave the expected 6-methyl-5-tosyl-1,2,3,4-tetrahydropyrimidin-2-imines. However, their acid-catalyzed dehydration led to mixtures of the latter compounds and the products of tosyl group migration, 4-tosylmethyl derivatives. This reaction was strongly influenced by the nature of the solvent. Plausible explanations of the obtained data were given. 相似文献
7.
2-Alkyl(aralkyl)sulfanyl-6-methylpyrimidin-4(3H)-ones and 4-alkyl(aralkyl)oxy-2-alkyl(aralkyl)-sulfanyl-6-methylpyrimidines having similar or different substituents on the sulfur and oxygen atoms were synthesized by alkylation of sodium salts derived from 6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-4-one and 2-alkyl(aralkyl)sulfanyl-6-methylpyrimidin-4(3H)-ones with alkyl (propyl, ethyl, allyl) and aralkyl [benzyl, m-phenoxybenzyl, p-(1-adamantylbenzyl)] halides. The effects of the alkyl (aralkyl) halide nature and solvent polarity on the rate of nucleophilic substitution and product yield were studied. 相似文献
8.
A general approach to 6-phenylthio-substituted 2,3,4,5-tetrahydro-1H-1,3-diazepin-2-ones based on the ring expansion reaction of 1,2,3,4-tetrahydropyrimidin-2-ones under the action of nucleophiles has been developed. The first step of the synthesis was preparation of N-[(2-benzoyloxy-1-tosyl)ethyl]urea by three-component condensation of 2-benzoyloxyethanal, urea and p-toluenesulfinic acid. Nucleophilic substitution of the tosyl group in the obtained sulfone with sodium enolates of α-phenylthioketones followed by cyclization-dehydration, and debenzoylation gave 4-hydroxymethyl-5-phenylthio-1,2,3,4-tetrahydropyrimidin-2-ones which were transformed into the 4-mesyloxymethyl-derivatives. Treatment of the latter with nucleophilic reagents, such as NaCN, sodium diethyl malonate, PhSNa, MeONa, NaBH(4), sodium succinimide, or potassium phthalimide, afforded the target multi-functionalized diazepinones. The obtained 6-phenylthio-diazepinones and their 6-tosyl-substituted analogues were converted into 3-substituted 1-carbamoyl-1H-pyrroles under acidic conditions as a result of ring contraction. Effective one-pot synthesis of the latter from 4-mesyloxymethyl-pyrimidines was realized using a ring expansion/ring contraction sequence. 相似文献
9.
高氯酸镁催化合成1,2,3,4-四氢嘧啶-2-酮 总被引:9,自引:0,他引:9
在高氯酸镁催化作用下,由醛、1,3-二羰基化合物、脲(硫脲)合成了一系列1,2,3,4-四氢嘧啶-2-酮,此合成方法反应温和、产率高,并且高氯酸镁具有能重复使用的优点. 相似文献
10.
Mário A. Marangoni Carlos E. Bencke Helio G. Bonacorso Marcos A.P. Martins Nilo Zanatta 《Tetrahedron letters》2018,59(2):121-124
An efficient synthesis of two new series of 6-aryl-4-trifluoromethyl-2H-pyran-2-ones and 6-aryl-4-carboxyethyl-2H-pyran-2-ones, obtained through the self-condensation reaction of 5-aryl-5-methoxy-3-(trifluoromethyl)penta-2,4-dienenitriles 3 and ethyl 4-aryl-2-(cyanomethylene)-4-methoxybut-3-enoates 4 respectively, is reported. The self-condensation reaction of the enoates 4 was performed in water in the presence of hydrochloric acid whereas the self-condensation reaction of the penta-2,4-dienenitriles 3 required the use of zinc bromide and hydrochloric acid in order to give the respective 2H-pyran-2-ones. Products were obtained up to 97% yield. 相似文献
11.
p-Toluenesulfinic acid is an effective catalyst for condensation of acetoacetic ester with urea and aliphatic or aromatic aldehydes, leading to formation of 4-substituted 6-methyl-5-ethoxycarbonyl-1,2,3,4-tetrahydropyrimidin-2-ones.M. V. Lomonosov State Academy of Fine Chemical Technology, Moscow 117571, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 979–982, July, 1998. 相似文献
12.
Ramendra Pratap 《Tetrahedron letters》2005,46(30):5025-5027
The one-pot substituent-directed regioselective synthesis of 1,7-diaryl-2-methyl-4H,5H-pyrano[3,4-c]pyran-4,5-diones 3 as the major and 3,4-diaryl-2-methyl-6-methylsulfanylbenzonitriles 4 as the minor products has been delineated through ring transformation of suitably functionalized 2H-pyran-2-ones 1 with aryl acetones 2. Under similar reaction conditions, 6-aryl-4-sec-amino-2H-pyran-2-ones 5 led, regioselectively, to 3,4-diaryl-2-methyl-6-sec-aminobenzonitriles 6. 相似文献
13.
Halocyclocarbamation of benzyl N-(1-phenyl-3-butenyl)carbamates afforded 6-functionalized 4-aryl-1,3-oxazinan-2-ones with moderate to excellent diastereoselectivity depending on the N-substituent. Importantly, in contrast to reported cyclocarbamations of homoallylic carbamates, which are generally trans-diastereoselective, cyclization of N-unsubstituted Cbz-protected homoallylamines led to cis-1,3-oxazinan-2-ones, predominantly. The use of N-benzylated and in situ prepared N-silylated derivatives resulted however in trans-selectivity. Transition states are proposed to explain the stereochemical influence of the N-substituent on the cyclocarbamations. The functionalized 1,3-oxazinan-2-ones could be further elaborated towards biologically or synthetically important 6-arylpiperidine-2,4-diones and 3-aryl-1,3-aminoalcohols. 相似文献
14.
Yu-wei RenXuerui Wang Weixia WangBing Li Zong-jun ShiWei Zhang 《Tetrahedron letters》2011,52(2):192-195
Photochemical and thermal cyclization of 4-(2-azidophenyl)-3,4-dihydropyrimidin-2-ones could afford fused indoles, such as 1,2,3a,9b-tetrahydro-4-methylenepyrimidino[5,4-b]indol-2-ones and 1,3,5,6,7a,12b-hexahydroquinazolino[9,4-b]indol-2,7-dione in high yields via nitrene electrophilic addition and rearrangement reactions. 相似文献
15.
Cyclocondesation of 3-aryl(heteryl)pyrazole-4-carbaldehydes with ethyl acetoacetate and urea (thiourea) in the presence of FeCl3 · 6H2O afforded 3-aryl(heteryl)-4-(4-pyrazolyl)-1,2,3,4-tetrahydropyrimidin-2-ones(thiones).__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 97–98.Original Russian Text Copyright © 2005 by Bratenko, Chornous, Vovk. 相似文献
16.
Anastasia A. Fesenko 《Tetrahedron letters》2007,48(48):8420-8423
A three-stage diastereoselective synthesis of (4R∗,5R∗,6S∗)-5-mercapto-4-methyl-6-phenylhexahydropyrimidin-2-one has been developed. The first stage involves the formation of 4-hydroxy-5-(4-methoxybenzylthio)-4-methyl-6-phenylhexahydropyrimidin-2-one by the reaction of N-[(phenyl)(tosyl)methyl]urea with the sodium enolate of 1-(4-methoxybenzylthio)propan-2-one. Reduction of the obtained compound by NaBH4-CF3COOH and removal of the p-methoxybenzyl protecting group results in the target compound. 相似文献
17.
A new synthesis of 2,3-dialkyl-4-carbomethoxyisoquinolin-1(2H)-ones and 6,7-dialkyl-8-carbomethoxy-1,6-naphthyridin-5(6H)-ones is reported. The process involves treatment of a β-enaminoester with 2-fluoro-5-nitrobenzoyl chloride, 2-fluorobenzoyl chloride or 2-chloronicotinoyl chloride followed by heating in the presence of base. The conversion, which proceeds by an N-acylation-SNAr reaction sequence, affords 50–86% yields when R1 is n-alkyl but ≤30% yields when R1 is α-branched. 相似文献
18.
A general four-step approach to 1,2,3,7,8,8a-hexahydropyrido[4,3-d]pyrimidin-2-ones via Staudinger/intramolecular aza-Wittig reaction of 5-acyl-4-(β-azidoalkyl)-1,2,3,4-tetrahydropyrimidin-2-ones promoted by PPh3 was developed. Synthesis of the starting pyrimidinones included preparation of 3-azidoaldehydes by the addition of hydrazoic acid to α,β-unsaturated aldehydes, transformation of 3-azidoaldehydes into N-[(3-azido-1-tosyl)alkyl]ureas followed by the reaction with enolates of dibenzoylmethane, benzoylacetone, acetylacetone, or ethyl 2,4-dioxo-4-phenylbutanoate and dehydration of the resulting products under acidic conditions. 相似文献
19.
Kamal A. Kandeel Ali M. Youssef Hany M. El-Bestawy Mohamed T. Omar 《Monatshefte für Chemie / Chemical Monthly》2002,133(9):1211-1219
Summary. N,N-Disubstituted 5-arylmethylidene-2-aminothiazol-4(5H)-ones reacted with diethyl malonate, ethyl benzoylacetate, acetylacetone, or cyclopentadiene in refluxing toluene and in
presence of powdered sodium to give the respective 5-arylmethylidene-2′-amino-2,5′-bithiazolylidene-4,4′-dione derivatives
in moderate yields. 5-Benzylidene-2-morpholin-4-yl-2-thiazol-4(5H)-one reacted with malononitrile in toluene and in presence of powdered sodium under mild conditions to afford the 1:1 adduct,
benzylmalononitrile, and 2-morpholin-4-yl-2-thiazol-4(5H)-one. However, similar treatment of 5-(4-methoxyphenylmethylidene)-2-morpholin-4-yl-2-thiazol-4(5H)-one with malononitrile yielded the 2,5′-bithiazolylidene-4,4′-dione derivative together with 4-methoxyphenylmethylidene
malononitrile. Treatment of 5-benzylidene- and 5-(4-methoxyphenylmethylidene)-2-morpholin-4-yl-2-thiazol-4(5H)-ones with 3-phenyl-4-oxo-2-thioxo-1,3-thiazolidine in refluxing toluene and in presence of powdered sodium produced 5-arylmethylidene-3-phenyl-4-oxo-2-thioxo-1,3-thiazolidines
in good yields. The structures of all products were deduced from microanalytical and spectroscopic data, mechanistic details
are discussed.
Corresponding author. E-mail: kamalkandeel@hotmail.com
Received November 5, 2001. Accepted (revised) December 17, 2001 相似文献
20.
The reactions of 2-(1-hydropolyfluoro-1-alkenyl)-4H-3,1-benzoxin-4-ones (2) with hydrazine hydrate and phenyl hydrazine were investigated. The reaction of 2 with hydrazine hydrate in ethanol under reflux condition readily gave 2-fluoroalkyl-4H-pyrazolo[5,1-b]quinazolin-9-ones (3) in high yields. The reaction of 2 with phenyl hydrazine, however, resulted in the formation of 2-(2-phenyl-5-fluoroalkyl-2H-pyrazol-3-yl) benzoic acids (7). Further treatment of 7 with PPA gave 1-phenyl-4,9-dihydro-3-fluoroalkyl-1H-pyrozolo[3,4-b]quinolin-4-ones (4) in 65-80% overall yields. 相似文献