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1.
4H-Chromenyl-tetrahydro-2H-pyrancarboxylates 3a–k have been conveniently prepared by the reaction of 3-formylchromones 1a–k and ethyl 4,4,4-trifluoro-3-oxobutanoate 2a with good yields. Thus obtained 4H-chromenyl-tetrahydro-2H-pyrancarboxylates 3a–k were reacted with amines 4a–e to provide series of 5-(2-hydroxybenzoyl)-2-(trifluoromethyl)-1,2-dihydropyridine-3-carboxylates 5a–o. The reaction proceeded via Michael addition (C-N bond formation) and followed by cleavage of chromone and pyran rings (C-O bond cleavage) in one pot. 相似文献
2.
G. A. Obanin A. S. Fokin Ya. V. Burgart O. V. Ryzhkov Z. E. Skryabina V. I. Saloutin O. N. Chupakhin 《Russian Chemical Bulletin》2000,49(7):1231-1236
Methods for the synthesis of the earlier unknownN-substituted 2-(5,6,7,8-tetrafluoro-4-oxo-1,4-dihydroquinolin-3-yl)glycoxylic acids their esters from copper chelate of ethyl
pentafluorobenzoylpyruvate were developed. The structure of intermediate ethyl 4-(R-amino)-2-oxo-3-pentafluorobenzoylbut-3-enoates
is discussed.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1234–1239, July, 2000. 相似文献
3.
The asymmetric reduction of ethyl 4-chloro-3-oxobutanoate (COBE) to ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) catalyzed by Aureobasidium pullulans CGMCC 1244 was performed in an aqueous/ionic liquid biphase system to improve the productivity and optical purity of (S)-CHBE. The influences of reaction parameters such as shaking rate, phase volumetric ratio, reaction temperature, initial substrate concentration, and pH were studied. In the aqueous/[bmim]PF6 biphase system and under the optimum reaction conditions of 30 °C, pH 6.6, rotation speed 180 r/min, and reaction time of 8 h, the conversion of COBE, the enantiomeric excess, and the concentration of (S)-CHBE were 95.6%, 98.5%, and 47.1 g/L, respectively. When the substrate was fed in batches under the condition of pH 6.6, the accumulated product concentration could reach up to 75.1 g/L. 相似文献
4.
Boris I. Usachev Sergey A. UsachevGerd-Volker Röschenthaler Vyacheslav Ya. Sosnovskikh 《Tetrahedron letters》2011,52(50):6723-6725
4-Aryl-6-(trifluoromethyl)-2H-pyran-2-ones and ethyl 4-aryl-6-(trifluoromethyl)-2-oxo-2H-pyran-3-carboxylates react with sodium azide to produce highly functionalized CF3-1,2,3-triazoles: 3-[5-(trifluoromethyl)-1,2,3-triazol-4-yl]cinnamic acids and monoethyl esters of [5-(trifluoromethyl)-1,2,3-triazol-4-yl]arylmethylidene malonic acids. 相似文献
5.
4-(2,6,10-Trimethyl-1,3,5,9-undecatetraenyl)benzoic acid (1) was synthesized starting from ethyl 4-formylbenzoate (2) and linalool. The key intermediate, ethyl 4-(2-methyl-3-oxo-1-propenyl)benzoate (5), was obtained by the addition of diethyl acetal (3), prepared from2, to ethyl 1-propenyl ether (EPE) followed by the hydrolysis of the resulting adduct.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 914–915, May, 1993. 相似文献
6.
V. F. Mironov L. M. Burnaeva I. A. Litvinov Yu. Yu. Kotorova A. B Dobrynin R. Z. Musin I. V. Konovalova 《Russian Chemical Bulletin》2004,53(8):1704-1710
The reaction of the di-O-trimethylsilyl derivative of 2-hydroxynicotinic acid with methyl phosphodichloridite afforded 2-methoxy-1,3,2-dioxaphosphorino[4,5-b]pyridin-4(4H )-one. The NMR spectrkscopic data suggest that the reaction of the latter with hexafluoroacetone produces unstable 2-methoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-4,5-dihydro-1,3,2-dioxaphosphepino[4,5-b]pyridine, which is readily transformed into 9-methyl-2,5-dioxo-4,4- bis(trifluoromethyl)-4,5-dihydro-1,3,2-dioxaphosphepino[4,5-b]pyrid-9-inium-2-oate. The structure of the hydrolysis product of the latter, viz., 1-methyl-3-(2-hydroxy-3,3,3-trifluoro-2- trifluoromethylpropanoyl)pyridin-2-one, was established by X-ray diffraction analysis.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1640–1646, August, 2004. 相似文献
7.
Ivana Bradiaková Tatiana Ďurčeková Naďa Prónayová Anton Gatial Alžbeta Krutošíková 《Chemical Papers》2009,63(5):586-591
2-[3-(Trifluoromethyl)phenyl]-4,5-dihydrofuro[3,2-c]pyridin-4-one (I) was prepared by a three-step synthesis. Its reaction with phosphorus sulfide rendered thione II which was methylated to 2-[3-(Trifluoromethyl)phenyl]-4-methylsulfanylfuro[3,2-c]pyridine (III). 5-Methyl-2-[3-(trifluoromethyl)phenyl]-4,5-dihydrofuro[3,2-c]pyridin-4-one (IV) was obtained by the reaction of I with methyl iodide in PTC conditions. The chlorine atom in derivate V was replaced with heterocyclic secondary amines via nucleophilic substitution and 4-substituted furopyridines VIa and VIb were thus prepared. 2-[3-(Trifluoromethyl)phenyl]furo[3,2-c]pyridine-4-carboxylic acid (VII) was obtained by hydrolysis of the corresponding carbonitrile Va. 相似文献
8.
A synthesis of novel derivatives of 6-methyluracil, 6-methyl-2-thioxo-, and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one
containing a 2-(phenoxy)ethyl substituent at position 5 of the pyrimidine ring has been carried out. It was found that 5-[2-(phenoxy)ethyl]
derivatives of 6-methyl-2-thioxo- and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one are obtained by the condensation of
the corresponding ethyl 3-oxo-2-(2-phenoxyethyl)butanoates with thiourea or guanidine. 6-Methyl-5-[2-(phenoxy)ethyl]uracils
can be prepared by treating 6-methyl-5-[2-(phenoxy)ethyl]-2-thioxo-2,3-dihydro-1H-pyrimidin-4-ones with an excess of aqueous
monochloroacetic acid solution.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1217, August, 2005. 相似文献
9.
Shubhangi C. Joshi Kunjbihari N. Trivedi 《Monatshefte für Chemie / Chemical Monthly》1992,123(6-7):557-564
Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement 相似文献
10.
The Knoevenagel condensations of 5-[3-(trifluoromethyl)phenyl]furan-2-carbaldehyde with seven compounds containing an active
methyl or methylene group have been studied. The compounds used were: methyl 2-cyanoacetate, malononitrile, 2-furylacetonitrile,
acetophenone, 2-thioxo-1,3-thiazolidin-4-one (rhodanine), 5,5-dimethylcyclohexane-1,3-dione (dimedone), and methyl 2-azidoacetate.
The effect of microwave irradiation on the condensation reactions was studied and compared with “’classical”’ conditions.
Thermolysis of methyl 2-azido-3-{5-[3-(trifluoromethyl)phenyl]-2-furyl}propenoate afforded methyl 2-[3-(trifluoromethyl)phenyl)]-4H-furo[3,2-b]pyrrole-5-carboxylate.
(2E)-3-{ 5-[3-(Trifluoromethyl)phenyl]-2-furyl}propenoic acid was converted to the corresponding azide, which was cyclized
on heating into 2-[3-(trifluoromethyl)phenyl)]-4,5-dihydrofuro[3,2-c]pyridin-4-one. The latter after successive action of
POCl3 and NH2NH2-Pd/C gave 2-[3-(trifluoromethyl)-phenyl]furo[3,2-c]pyridine.
Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 825–831, June, 2006. 相似文献
11.
Dz. Sile V. A. Slavinska G. Rozental J. Popelis Yu. Balodis E. Lukevics 《Chemistry of Heterocyclic Compounds》2002,38(3):287-291
We have developed a method for the synthesis of ethyl 4-(3-pyridyl)- and 4-(4-pyridyl)-2-oxobutenoates by condensation of 3-pyridinecarbaldehyde and 4-pyridinecarbaldehyde monohydrate respectively with ethyl pyruvate, esterifiction of the target acids, and hydrolysis of the corresponding ethyl ester ketals in the presence of FeCl3·6H2O. 相似文献
12.
V. Ya. Sosnovskikh B. I. Usachev M. N. Permyakov D. V. Sevenard G.-V. Röschenthaler 《Russian Chemical Bulletin》2006,55(9):1687-1689
Condensation of 2-trifluoromethylchromone with diethyl malonate, ethyl cyanoacetate, and Meldrum’s acid gave the corresponding
methylidene derivatives of 2-trifluoromethyl-4H-chromene. Nucleophilic 1,6-addition of an excess of Me3SiCF3 in the presence of Me4NF to those obtained from the former two compounds afforded 4-substituted 2,2-bis(trifluoromethyl)-2H-chromenes.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1628–1630, September, 2006. 相似文献
13.
Ethyl 1-aryl-5-(trifluoromethyl)-1H-pyrazole-4-carboxylates 2 were prepared by the condensation of arylhydrazines with ethyl 3-ethoxy-2-(trifluoroacetyl)-2-propenoate (1a) at low temperature. The corresponding acids were also synthesized. X-ray diffraction analysis of an amide derivative 4 verified the position of the trifluoromethyl group on the pyrazole ring. 相似文献
14.
Vladimir Mironov Gulnara Ivkova Liliya Abdrakhmanova Liliya Burnaeva Kristina Kuzmina 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):162-163
Abstract 2-(5-Methyl-2-phenyl-2Н-1,2,3-diazaphosphol-4-yl)-4H-benzo[d]-1,3,2-dioxaphosphorin-4-one 1 readily reacts with hexafluoroacetone, mesoxalic acid diethyl ester, trifluoropyruvic acid ethyl ester and chloral to give 2-(5-methyl-2-phenyl-2H-1,2,3-dizaphosphole-4-yl)-derivatives of 1,3,2- and 1,4,2-dioxaphosphepines. 相似文献
15.
Cornelis M. Moorhoff 《Monatshefte für Chemie / Chemical Monthly》2003,134(1):61-67
Summary. Wittig condensations of α,β-unsaturated carbonyl compounds with ethyl 3-ethoxy-4-(triphenylphosphoranylidene)-2-butenoate gave good
to high yields of (2E,4E,6E)-ethyl 3-ethoxy-2,4,6-alkatrienoates. Some of last mentioned compounds were almost quatitatively hydrolysed to (4E,6E)-ethyl 3-oxo-4,6-alkadienoates. This method can therefore be used as an attractive alternative for the preparation of unsaturated
conjugated β-keto esters previously prepared in very low yields from α,β-unsaturated carbonyl compounds and ethyl 3-oxo-4-(triphenylphosphoranylidene)butanoate.
Present address: Boron Molecular Pty. Ltd., PO Box 756, Noble Park, VIC 3174, Australia. E-mail: cmoorhoff@boronmolecular.com
Received June 17, 2002; accepted June 21, 2002 相似文献
16.
Anil Valeru Imran Khan Bin Liu Bhavanarushi Sngepu Narender Reddy Godumagadda 《合成通讯》2018,48(17):2226-2231
A series of novel 6-(trifluoromethyl)-1,2,3,4-tetrahydropyrimidine-5-carboxylate derivatives were obtained in good yields from ethyl 4,4,4-trifluoro-3-oxobutanoate, urea, and aryl aldehyde via Biginelli multicomponent reaction. All the corresponding products 4a–4p were examined against four human cancer cell lines (A549, HepG2, COLO205 and DU145) and compounds 4e, 4i, and 4?m which showed promising anticancer activity have been identified. 相似文献
17.
Ivana Bradiaková Naďa Prónayová Anton Gatial Alžbeta Krutošíková 《Chemical Papers》2008,62(4):428-434
(E)-3-{5-[3-(Trifluoromethyl)phenyl]furan-2-yl}propenoic acid (I) was prepared from 5-[3-(tri-fluoromethyl)phenyl]furan-2-carbaldehyde under the Doebner’s conditions. The obtained acid was
converted to the corresponding azide II, which was cyclized by heating in diphenyl ether to 2-[3-(trifluoromethyl)phenyl]-4,5-dihydrofuro[3,2-c]pyridin-4-one (III). This compound was aromatized with phosphorus oxychloride to chloroderivative IV which was reduced with H2NNH2-Pd/C to the title compound V. 2-[3-(Trifluoromethyl)phenyl]furo[3,2-c]pyridin-5-oxide (VI) was synthesized by reaction of V with 3-chloroperoxybenzoic acid in dichloromethane. On treatment of VI with benzoyl chloride and potassium cyanide (Reissert-Henze reaction), corresponding 2-[3-(trifluoromethyl)phenyl]furo[3,2-c]pyridine-1-carbonitrile (VII) resulted. 5-Amino-2-[3-(trifluoromethyl)phenyl]furo[3,2-c]pyridin-5-ium-4-methylbenzene sulfonate (VIII) was prepared by direct N-amination of the title compound V with 1-[(aminooxy)sulfonyl]-4-methylbenzene in dichloromethane. Then, VIII was transformed to a non-isolated zwitterionic N-imid IX which afforded the corresponding furo[3,2-c]pyrazolo[1,5-a]pyridine carboxylic acid esters X, XI by 1,3-dipolar cycloaddition reactions with dimethyl but-2-ynedionate (DBD) or ethyl propiolate. The structures of all compounds
were confirmed by their IR and NMR spectra.
Presented at the 1st International Conference “Applied Natural Sciences” on the occasion of 10th anniversary of the University
of St. Cyril and Methodius, Trnava, 7–9 November 2007. 相似文献
18.
Rodinovskaya L. A. Gromova A. V. Shestopalov A. M. Nesterov V. N. 《Russian Chemical Bulletin》2003,52(10):2207-2213
Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis. 相似文献
19.
The leaves of Cinnamomum reticulatum Hay were extracted successively with hexane and acetone successively. Dipentadecyl ketone, n-dotriaconyl alcohol, 2-(4-hydroxy-3-methoxyphenyl)ethyl hexa- and octacosanoates ( two new esters from hexane extract ), β-sitosterol, fatty acid, vanillin, p-hydroxybenzaldehyde, genkwanin, vanillic acid, p-hydroxybenzoic acid, β-sitosteryl-l-β-glucopyranoside, meso-erythritol, glucose, and 4-(2-hydroxyethyl)-2-methoxyphenyl-l-β-D-glucopyranoside (from the acetone extract) were isolated. The structures of the new esters were elucidated by chemical and physical evidence. 相似文献
20.
Boris I. Usachev Vyacheslav Ya. Sosnovskikh Mikhail A. Shafeev Gerd-Volker Röschenthaler 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1315-1319
Abstract Alkyl 2-mercaptophenyl ketones react with trifluoroacetic anhydride in the presence of triethylamine to give 2-(trifluoromethyl)-4H-thiochromen-4-ones, which are transformed into the corresponding pyrazoles by treatment with hydrazine hydrate and into 1,1-dioxides by oxidation with H2O2 in AcOH. 相似文献