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1.
Reaction of ethyl or methyl 3-oxoalkanoates with N,N-dimethylformamide dimethyl acetal gave, generally in excellent yields, a series of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates II which reacted with phenylhydrazine to afford the esters of 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic acids III in high yields. Esters III were hydrolyzed to the relative 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic acids which were converted by heating to 5-substituted 1-phenyl-1H-pyrazoles in excellent yields. Reaction of II with methylhydrazine afforded in general a mixture of 3- and 5-substituted ethyl 1-methyl-1H-pyrazole-4-carboxylates with the exception of IIg , which gave in high yield methyl 5-benzyl-1-methyl-1H-pyrazole-4-carboxylate, which was hydrolyzed to the relative pyrazolecarboxylic acid. This afforded by heating 5-benzyl-1-methyl-1H-pyrazole in quantitative yield. 相似文献
2.
Pietro Schenone Laura Sansebastiano Luisa Mosti 《Journal of heterocyclic chemistry》1990,27(2):295-305
Reaction of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates with N-C-N dinucleophiles such as guanidine, acetamidine or benzamidine afforded in high yields the relative esters of 4-substituted 2-amino-, 2-methyl- or 2-phenyl-5-pyrimidinecarboxylic acids, respectively. These esters were hydrolyzed to the corresponding carboxylic acids, which were converted by heating to 4-substituted 2-pyrimidinamines, 2-methyl or 2-phenylpyrimidines, respectively, generally in excellent yields. The 4-unsubstituted ethyl 2-amino-, 2-methyl- and 2-phenyl-5-pyrimidinecarboxylates were obtained in moderate yields by reaction of the above dinucleophiles with ethyl 2,2-diformylacetate. These esters were hydrolyzed and the corresponding acids (with the exception of the 2-methyl derivative) were decarboxylated to give 2-pyrimidinamine and 2-phenylpyrimidine in satisfactory yields. 相似文献
3.
The reaction of open-chain and cyclohexane sym-2-dimethylaminomethylene-1,3-diones with amidines and guanidine in refluxing ethanol gave, generally in good yields, a series of 5-acylpyrimidines and 7,8-dihydroquinazolin-5(6H)-ones, respectively. With formamidine (and in part acetamidine), 2-formylimino-1,3-diones were formed in general, as sole products or mixtures with the corresponding pyrimidines or dihydroquinazolinones. 相似文献
4.
The reaction of open-chain sym-2-dimethylaminomethylene-1,3-diones Ia-d with sodium cyanoacetamide gave, generally in good yields, 6-substituted 5-acyl-1,2-dihydro-2-oxo-3-pyridinecarbonitriles IIa-d, whereas cyclohexane sym-2-dimethylaminomethylene-1,3-diones Ie-h afforded in general a mixture of 1,2,5,6,7,8-hexahydro-2,5-dioxo-3-quinolinecarbonitriles and 5,6,7,8-tetrahydro-2,5-dioxo-2H-1-benzopyran-3-carboxamides, the latter being isolated in two cases. The reaction of Ie-h with cyanoacetamide in refluxing anhydrous ethanol gave 1,2,5,6,7,8-hexahydro-2,5-dioxo-3-quinolinecarboxamides IIIe-h in excellent yields, whereas Ia-d did not react with the exception of Ia which afforded in good yield 3-pyridinecarboxamide IlIa. Other 3-pyridine-carboxamides were obtained by partial hydrolysis of nitriles IIb,d. 3-Pyridine and 3-quinoline carboxamides were hydrolyzed in satisfactory yields with hydrochloric acid to the corresponding carboxylic acids, which were decarboxylated in good yields to 5-acyl-2(1H)-pyridinones and 7,8-dihydro-2,5(1H,6H)-quinolinediones, respectively, by reflux in quinoline containing a catalytic amount of copper powder. 相似文献
5.
The reaction of open-chain and cyclohexane sym-2-dimethylaminomethylene-1,3-diones with hydroxylamine hydrochloride in refluxing methanol gave in good to moderate yields a series of 5-(alkyl)(phenyl)-4-acylisoxazoles and 6,7-dihydro-1,2-benzisoxazol-4(5H)-ones, respectively. As 3-unsubstituted isoxazoles, all these compounds easily isomerized with sodium methoxide to the corresponding 2-cyano-1,3-diones in high yields. 相似文献
6.
Reaction of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates with hydroxylamine hydrochloride in methanol solution afforded in high yields the relative esters of 5-substituted 4-isoxazolecarboxylic acids II . These esters were hydrolyzed generally with concentrated hydrochloric acid-acetic acid mixtures to the corresponding carboxylic acids in satisfactory yields. Ethyl or methyl esters II isomerized with sodium ethoxide or methoxide, respectively, to the corresponding esters or hemiesters of 2-cyano-3-oxoalkanoic acids generally in excellent to satisfactory yields. Reaction of methyl 5,5-dimethyl-3-dimethylaminomethylene-2,4-dioxohexanoate with hydroxylamine hydrochloride afforded in moderate yield methyl 4-(2,2-dimethyl-1-oxopropyl)-5-isoxazolecarboxylate, which was converted by acid hydrolysis as above to 4-t-butyl-4-hydroxyfuro[3,4-d]isoxazol-6-(4H)-one. 相似文献
7.
L. E. Neiland 《Chemistry of Heterocyclic Compounds》1970,6(5):597-600
Condensation of 2-hydroxymethylnicotinic and 2-hydroxymethylquinoline-3-carboxylic acid lactones with aromatic aldehydes in the presence of sodium methoxide gives, respectively, 2-aryl-4-azaindan-1,3-diones and 2-aryl-4-aza-5,6-benzindan-1,3-diones. Alkylation of 2-aryl-4-azaindan-1,3-diones with diazomethane gives the N-methylbetaines. According to the IR spectra, in the solid state the 4-azaindan-1,3-diones seemto have a strongly polarized enol structure.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 5, pp. 647–650, May, 1970. 相似文献
8.
A squarate-based synthesis of 2-ferrocenylidene-4-cyclopentene-1,3-diones is described. When refluxed in dioxane at 100 °C, heated with silica gel as a solvent free grinded solid mixture at 125 °C or stirred with silica gel in ethyl acetate at room temperature, 4-ferrocenylethynyl-4-hydroxy-2-cyclobutenones, prepared from ethynylferrocene and 3-cyclobutene-1,2-diones, afforded 2-ferrocenylidene-4-cyclopentene-1,3-diones as the major or single product of the reaction. In some cases, ferrocenyl quinones also resulted from these reactions as the minor products. The major or exclusive formation of 2-ferrocenylidene-4-cyclopentene-1,3-diones is attributed to the radical-stabilizing ability of the ferrocenyl group. 相似文献
9.
T. S. Khlebnikova V. G. Isakova F. A. Lakhvich 《Russian Journal of Organic Chemistry》2009,45(4):519-522
Treatment of 2-perfluoroalkanoyl-5.5-dimethylcyclohexane-1,3-diones with a solution of diazomethane in diethyl ether led to the formation of the corresponding enol ethers and 3-hydroxy-6,6-dimethyl-3-perfluoroalkyl-2,3,6,7-tetrahydrobenzofuran-4(5H)-ones. The latter underwent dehydration on heating in boiling benzene in the presence of a catalytic amount of p-toluenesulfonic acid to give 6,6-dimethyl-3-perfluoroalkyl-6,7-dihydrobenzofuran-4(5H)-ones. 相似文献
10.
D. B. Rubinov A. G. Mikhailovskii F. A. Lakhvich 《Chemistry of Heterocyclic Compounds》1992,28(12):1385-1388
The reaction of cyclohexane -triketones with 6-hydrazinophenanthridine gave enehydrazinodiketones, which were cyclized upon heating to give derivatives of 1-(phenanthridin-6-yl)-4,5,6,7-tetrahydroindazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.12, pp. 1617–1620, December 1992. 相似文献
11.
V. L. Gein E. V. Shumilovskikh É. V. Voronina Yu. S. Andreichikov 《Chemistry of Heterocyclic Compounds》1992,28(1):27-30
The reaction of 2-aminopyridine with 1,5-diaryl-4-ethoxycarbonyltetrahydropyrrole-2,3-diones gave 11 complexes, which are converted to N-(2-pyridyl)-1,5-diaryl-3-hydroxy-2-oxo-2,5-dihydropyrrole-4-carboxamides when they are heated above their melting points without a solvent. The character of the hydrogen bonds in the complexes obtained is discussed.See [1] for Communication 20.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 32–36, January, 1992. 相似文献
12.
13.
Heating 2-cyanopyridine and hydrazine hydrate at 100 °C and reheating the resultant liquid with pyridine-2-carboxaldehyde yielded a red semi-solid. On adding aqueous KOH, a mixture of 1-(3,5-bis(2-pyridyl)-1,2,4-triazolyl)-3-(2-pyridyl)imidazo[1,5-a]pyridine (2a) and 1-((2-pyridyl)methanimine)-3-(2-pyridyl)imidazo[1,5-a]pyridine (2b) precipitated and from the filtrate 3,5-bis(2-pyridyl)-1,2,4-triazole (1) was isolated. Similar compounds were obtained from two other pyridinecarboxaldehydes. 相似文献
14.
2-Pheny1-4-azaindan-1,3-dione and 2-(p-dimethylaminophenyl)-4-azaindan-1,3-dione are synthesized by condensing 4-azaphthalide with benzaldehyde and p-dimethylaminobenzaldehyde. 4-Azaphthalide reacts with p-nitrobenzaldehyde in hot acetic anhydride to give 3-(p-nitrobenzylidene)-4-azaphthalide, rearranged by sodium methoxide to 2-(p-nitrophenyl)-4-azaindan-1,3-dione. 2-Phenyl-and 2-(p-nitrophenyl)-4-azaindandiones are also obtained by sodium methoxide rearrangement of the products of reaction of quinolinic anhydride with phenylacetic and p-nitrophenylacetic acids. 2-Aryl-4-azaindandiones are deeply colored substances only slightly soluble, and without sharp melting points. They undergo methylation at the nitrogen atom, to give N-methylbetaines. The IR absorption spectra show that 2-ary]-4-azaindandiones exist in a strongly polarized enol form in the solid state. 相似文献
15.
T.S. Khlebnicova V.G. Isakova A.V. Baranovsky E.V. Borisov F.A. Lakhvich 《Journal of fluorine chemistry》2006,127(12):1564-1569
A one-pot synthesis of 2-perfluoroalkanoylcyclohexane-1,3-diones via C-acylation of cyclohexane-1,3-diones with N-perfluoroacylimidazole as an acylating agent is reported. A reaction was examined with isolated N-trifluoroacetylimidazole and with N-perfluoroacylimidazoles generated in situ from perfluorocarboxylic acid anhydrides or perfluorocarboxylic acids. 相似文献
16.
T. S. Khlebnikova Yu. A. Piven’ V. G. Isakova F. A. Lakhvich 《Russian Journal of Organic Chemistry》2012,48(10):1277-1282
2-Perfluoroalkanoylcyclopentane-1,3-diones were synthesized for the first time by acylation of cyclopentane-1,3-dione with perfluorocarboxylic acids in the presence of 1,1??-carbonyldiimidazole or with perfluorocarboxylic anhydrides in the presence of imidazole. 2-Perfluoroalkanoylcyclopentane-1,3-diones were selectively reduced to 2-(1-hydroxyperfluoroalkyl)cyclopentane-1,3-diones by the action of triethylsilane in trifluoroacetic acid in the presence of a catalytic amount of lithium perchlorate. Treatment of the title compounds with oxalyl chloride and subsequent reaction with 2 equiv of primary amine (4-fluoroaniline, 4-fluorobenzylamine, 3,4-difluoroaniline, 3-trifluoromethylbenzylamine) gave the corresponding 3-arylamino-2-perfluoroalkanoylcyclopent-2-en-1-ones. 相似文献
17.
Synthesis of pharmaceutically important 1,5-disubstituted-4-haloimidazoles starting from α-aminonitriles is described. Some 1D and 2D NMR spectral features of these imidazoles are discussed. 相似文献
18.
N. V. Pchelintseva D. A. Tsimbalenko O. V. Fedotova 《Russian Journal of Organic Chemistry》2007,43(9):1285-1290
Halogenation of 3-(4-methoxyphenyl)-1,5-diphenylpent-2-ene-1,5-dione, 3-(4-methoxyphenyl)-1,5-diphenylpentane-1,5-dione, and 2-[1-(4-methoxyphenyl)-3-oxo-3-phenylpropyl)-1,2,3,4-tetrahydroaphthalen-one with bromine, chlorine, and dichloro(phenyl)-λ3-iodane leads to formation of the corresponding monobromo-, dichloro-, or trichloro-substituted 1,5-diketones, depending on the conditions. Halogenation of the aliphatic chain and methoxyphenyl substituent can be accompanied by heterocyclization to give pyrylium salts. 相似文献
19.
M. S. Klyavlin T. K. Tkachenko L. P. Salagaeva S. S. Zlotskii D. L. Rakhmankulov 《Chemistry of Heterocyclic Compounds》1991,27(8):824-825
The insertion of dihalocarbenes into the C(2)-H bond of cis- and trans-2-alkyl-4-propyl-1,3-dioxolanes leads to mixtures of stereoisomers.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1030–1031, August, 1991. 相似文献
20.
A. A. Akhrem F. A. Lakhvich V. A. Khripach I. B. Klebanovich 《Chemistry of Heterocyclic Compounds》1975,11(3):285-289
A new method was developed for the synthesis of 2-acylcyclohexane-1,3-diones from the adducts of 1,3-dipolar cycloaddition of nitrile oxides to cyclohexenones. The method is examined in the case of the preparation of 2-acetyl-,2-enanthoyl-, and 2-benzoyldimedone. 相似文献