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1.
A. M. Sipyagin V. V. Kolchanov A. T. Lebedev N. K. Karakhanova 《Chemistry of Heterocyclic Compounds》1997,33(11):1306-1314
The reactions of isomeric tetrachlorocyanopyridines with potassium ethylxanthate were studied. It was found that tetrachloro-2-cyanopyridine
was converted successively into 4-mono- and then 3,4-bisethylxanthate derivatives. In the presence of potassium ethylxanthate
the last derivative undergoes intramolecular cyclization with the formation of derivatives of 1,3-dithiolo[4,5-c]pyridine.
In the case of other initial polychloropyridines processes involving substitution of the chlorine atoms by the ethylxanthate
fragment, sometimes accompanied by the loss of COS molecules, were observed instead of heterocyclization.
For Communication 13, see [1].
Chernogolovka Institute of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432. M. V. Lomonosov Moscow State
University, Moscow 119899. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1510–1520, November, 1997. 相似文献
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Catalytic hydrogenation of a totally synthetic mixture of (±)-3-methoxy-14-methyl-14α-estra-1,3,5( 10), 9(11)-tetraen-17-one(1) and the corresponding 1,3,5(10),8-tetraen-17-one (2) gives a mixture of 14α-methyl-8β,9β-, -8α,9α-, and -8β,9α-estrones, which is converted into the 17β-hydroxy-mixtures. t-Butylation gives a separable mixture of the three isomers, of which (±)-17β-t-butoxy-3 methoxy-14-methyl-9β,14α-estra-1,3,5(10)-triene(6) is the major component. The corresponding 14α-methylestradiols are prepared. A practical synthesis of (±)-14-methyl-14α-estra-1,3,5(10), 6,8-pentaene-3,17β-diol(25) is described, and it is shown that DDQ dehydrogenation of 1,3,5(10),9(11)-tetraenes in this series leads exclusively to the corresponding 1,3,5(10),6,8,11-hexaenes, whereas that of 1,3,5(10),8-tetraenes gives only 1,3,5(10),6,8-pentaenes. 相似文献
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Condensation of 3-methyl-3-buten-1-ol with pentanal or acetone occurs on metal salt surfaces at room temperature to give di- and tetrahydropyrans.For Communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1019–1021, August, 1990. 相似文献
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Nemtarev A. V. Mironov V. F. Aniskin A. S. Baranov D. S. Krivolapov D. B. Musin R. Z. Vasilevskii S. F. 《Russian Chemical Bulletin》2016,65(5):1299-1307
Russian Chemical Bulletin - Reactions of 2,2,2-trichlorobenzo-1,3,2-dioxaphosphole with 2-, 3-, 4-methoxyphenyl-, 3,4-dimethoxyphenyl- and 2,3,4-trimethoxyphenylacetylenes furnished... 相似文献
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Tomilov Yu. V. Guseva E. V. Volchkov N. V. Shulishov E. V. 《Russian Chemical Bulletin》2001,50(11):2113-2120
The reactions of diazomethane and diazocyclopropane generated in situ with 1,1,2,2-tetrafluoro-3-vinylcyclobutane (1) and 2,3,3-trifluoro-1-vinylcyclobutene (2) proceeded at the double bond of the substituent as the 1,3-dipolar cycloaddition to form the corresponding 1-pyrazolines. Under the conditions of thermolysis (340—400 °C), the resulting cyclobutylpyrazolines 4 and 5 selectively lost the dinitrogen molecule to generate 3-cyclopropyl-1,1,2,2-tetrafluorocyclobutane (6) or 1,1,2,2-tetrafluoro-3-spiropentylcyclobutane (7), respectively, in high yields. In the presence of Pd(acac)2, the reactions of these fluorine-containing unsaturated compounds and 2-chloro-1,1,2-trifluoro-3-vinylcyclobutane (3) with diazomethane gave rise directly to cyclopropane derivatives 6, 11, and 12, respectively. The reactions of compounds 1 and 2 with methyl diazoacetate in the presence of Rh2(OAc)4 proceeded analogously to yield cis- and trans-disubstituted cyclopropanes. 相似文献
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3 When 11-diethyl- and 3, 11-di-n-propyl-14-hydroxy-14-azadispiro[5.1. 5.2]pentadec-9-ene-7, 15-dione (E-IV and n-Pr-IV) are heated with polyphosphoric acid at 55–65°, the 14-hydroxyl group cyclizes at the 11-carbon to form E-VI and n-Pr-VI, the structures of which have been established. Compounds P-IV, i-Pr-IV and t-B-IV do not cyclize under these conditions. The Beckmann rearrangement of 12-hydroxy-12-azadispiro[4.1.4.2]tridec-8-ene-6, 13-dione-6-oxime (P-I) with polyphosphoric acid at 40–50° formed only the normal product, P-II, which could not be cyclized. Compound P-IV was the only ketone of this series which would add hydrogen cyanide to form a cyanohydrin. 相似文献
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I. S. Alfer'ev N. V. Mikhalin I. L. Kotlyarevskii L. M. Vainer 《Russian Chemical Bulletin》1987,36(4):786-790
Conclusions A study has been made of the reaction of vinylidenediphosphonic acid with aliphatic and aromatic thiols, resulting in the formation of the previously unknown 2-alkyl(aryl)-thioethylidene-1, 1-diphosphonic acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 860–864, April, 1987. 相似文献
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O. A. Rakitin V. A. Ogurtsov T. I. Godovikova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1990,39(7):1469-1471
We have studied the reaction of nitrile oxides with nitrogen tetroxide. It was shown that the reaction is selective: acetonitrile oxide yields ethylnitrolic acid, -oximinophenylacetonitrile oxide gives a mixture of isomers of phenylnitrofuroxan, and aromatic nitrile oxides give aryltrinitromethanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1620–1622, July, 1990. 相似文献
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Pelipko V. V. Adyukov I. S. Baichurin R. I. Makarenko S. V. 《Russian Journal of General Chemistry》2020,90(3):493-494
Russian Journal of General Chemistry - The reactions of alkyl-3-nitroacrylates with semicarbazide as representative of polynitrogen nucleophiles proceeds at room temperature in a solution of... 相似文献
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T. É. Bezmenova T. S. Lutsii A. F. Rekasheva Yu. N. Usenko 《Chemistry of Heterocyclic Compounds》1975,11(8):925-930
In contrast to alkyl esters of carboxylic acids, 3-acyloxysulfolanes on reaction with nucleophilic reagents readily split out a carboxylic acid to give 2-sulfolene, which then reacts with compounds containing a labile hydrogen atom. On the basis of data on the kinetics of alkaline hydrolysis of benzoates, a scheme for elimination of the acid that includes the intermediate formation of a transition state of the E1CB type is proposed. 相似文献
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O. G. Kuzueva Ya. V. Burgart V. I. Saloutin O. N. Chupakhin 《Russian Chemical Bulletin》1999,48(10):1937-1941
Fluorine-containing alkyl 2-cyano-3-oxocarboxylates were synthesized for the first time by the reaction of ethyl cyanoacetate
with fluorine-substituted carboxylic acid halides or alkyl carboxylates. The reactions with hydrazine hydrate, phenylhydrazine,
ando-phenylenediamine give hydrazinium (ammonium) enolates or products of acid decomposition.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1961–1965, October, 1999. 相似文献