Mercuration of α- and γ-methylpyrylium salts with mercuric acetate and trifluoroacetate

Mercury-containing methylpyrylium perchlorates were synthesized by mercuration of - and -methylpyrylium perchlorates with mercuric acetate and trifluoroacetate. A mechanism is proposed for the mercuration reaction. The salts obtained undergo decomposition upon reaction with mineral acids to give the starting methylpyrylium salts, while bromomethylpyrylium perchlorates are formed upon reaction with bromine as a result of cleavage of the C-Hg bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 881–886, July, 1981.     

Reaction of α and γ-methylpyrylium salts with orthoesters

The reaction of orthoesters with α- and γ-methylpyrylium salts gives 2- and 4-alkoxyvinyl-pyrylium salts the acid hydrolysis of which leads to 2- and 4-hydroxyvinylpyrylium salts and the alkaline hydrolysis to pyranylideneacetaldehydes.     

Radical reactions of ethyl orthoformate with 3,3,3-trifluoropropene

Conclusions The radical reaction of 3,3,3-trifluoropropene with ethyl orthoformate largely leads to the formation of the adduct, EtOC(O)OCH(Me)CH₂CH₂CF₃ due to rearrangement of the intermediate radicals with 1,5 hydrogen atom migration.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp.1418–1420, June, 1985.     

Reactions of ethyl 4-amino-6-(ethoxycarbonylmethyl)-2-phenylpyrimidine-5-carboxylate with hydrazines

New substituted 4,6-diamino-7-hydroxypyrido[4,3-d]pyrimidin-5(6H)-ones were synthe-sized by treatment of ethyl 4-amino-6-(ethoxycarbonylmethyl)-2-phenylpyrimidine-5-car-boxylic acid with hydrazine hydrate and phenylhydrazine. In the case of methylhydrazine, the reaction proceeded in an unusual way and afforded a product identified, relying on NMR data, as functionally substituted 8-(5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-7-ylidene)-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine comprising two amineimide fragments. A diacetyl derivative of this compound was obtained.     

Structure of condensation product of ethyl orthoformate with acetamide

Conclusicns Independent of the reaction conditions employed, trisacetylaminomethane is formed when ethyl orthoformate is reacted with acetamide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 888–889, April, 1971.     

Reaction of 3,4-dicyano-5-aminopyrazole with ethyl orthoformate

The condensation of 3,4-dicyano-5-aminopyrazole with ethyl orthoformate was studied. Under severe conditions (150 °C) the principal reaction product is N-ethyl-3,4-dicyano-5-ethoxymethylaminopyrazole. Alkylation of the pyrazole ring does not occur at 100 °C, but 3,4-dicyano-5-ethoxymethyleneaminopyrazole is formed. Isomeric 1- and 2-ethyl-4-aminopyrazolo[2,4-d]pyrimidine-3-carboxylic acid methyl imino esters were obtained by the action of a methanol solution of ammonia on the principal reaction product. This constitutes evidence that N-ethyl-3,4-dicyano-5-ethoxymethyleneaminopyrazole is a mixture of 1- and 2-ethyl-3,4-dicyano-5-ethoxymethyleneaminopyrazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1682–1685, December, 1982.     

4-hydroxy-2-quinolones. 41. Reaction of hydrazides of 1-R-2-oxo-4-hydroxyquinoline-3-carboxylic acids with ethyl orthoformate

The boiling of hydrazides of 1-R-2-oxo-4-hydroxyquinoline-3-carboxylic acids in an excess of ethyl orthoformate leads to the formation of ethyl esters of the corresponding quinoline-3-carboxylic acids, the structure of which was confirmed by X-ray diffraction analysis.For the Communication 40, see [1].National Pharmaceutical Academy of Ukraine, Kharkov 310002. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 207–211, February, 2000.     

Reactions of 4-methoxypyrylium salts with secondary amines

4-Aminopyrylium derivatives were prepared from secondary amines and 4-methoxy-2,6-dimethylpyrylium perchlorate ( 1a ) and the corresponding 2,6-diphenyl derivative. Excess amine or elevated temperature resulted in the addition of two equivalents of amine to 1a . The reactions of the aminopyrylium salts with hydroxide, ammonia, primary amines, hydrazines, cyanoacetamides, ethyl cyanoacetate, malononitrile, nitromethane, sodium sulfide, and a Grignard reagent are described.     

Reactions of sym-octahydrothioxanthylium salts with bases and structure of 4-(sym-octahydrothioxanthen-9-yl)-1,2,3,5,6,7,8-heptahydro-2H-thioxanthene

The reaction of sym-octahydrothioxanthylium salts with pyridine or aqueous sodium bicarbonate leads to the formation of 4-(sym-octahydrothioxanthen-9-yl)-1,2,3,5,6,7,8-heptahydro-2H-thioxanthene, whose structure was established by x-ray diffraction analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 479–482, April, 1989.     

Reactions of N-(4-methoxybenzylidene)-N,N-dialkyliminium and 2-(4-methoxyphenyl)pyridinium salts with aliphatic amines

The reaction of 4-methoxybenzylideneiminium salts with methylamine and dimethylamine on heating results in replacement of the MeO group by an alkylamino-group, whereas the reaction with piperidine affords 3,5-bis-(4-methoxybenzyl)pyridine. N-Methyl-2-(4-methoxyphenyl)pyridinium iodide on treatment with methylamine undergoes dealkylation to the arylpyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1226–1229, September, 1990.     

Reactions of 4-halo-2-alken(arylen)ylphosphonium salts with binucleophiles

Phosphonium salts with a 4-bromo-3-chlorobut-2-enyl or a 3-chlorobuta-1,3-dienyl group react with phenylhydrazine to give phenylhydrazones of corresponding 4-phospohonio-substituted 2-chloro-2-butenals. Reactions of phosphonium salts containing a 4-bromo-3-chlorobut-2-enyl group with a series of binucleophiles were studied. Under the action of urea, 1,4-dehydrobromination takes place to form a salt with a conjugated diene group, which undergoes partial 3,4-3,4-cyclization under the reaction conditions. Nucleophilic substitution reactions of [o-(bromomethyl)benzyl]triphenylphosphonium bromide with binucleophiles were also carried out.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 1992–1997.Original Russian Text Copyright © 2004 by Ovakimyan, Barsegyan, Pogosyan, Kikoyan, Panosyan, Indzhikyan.This revised version was published online in April 2005 with a corrected cover date.     

Reactions of indoles with 2- and 4-hydroxybenzyl alcohols

A procedure has been proposed for the synthesis of 1H-indolylmethylphenols by reaction of hydroxybenzyl alcohols with indoles under conditions implying thermal generation of o- and p-methylenequinones. The mechanism of formation and spectral parameters of the products are discussed.     

Bis[2-(4-pyridyl)ethyl](2-cyanoethyl)phosphine Oxide: Synthesis and Reactions with 1,4-Dihalobutanes

Russian Journal of General Chemistry - Bis[2-(4-pyridyl)ethyl]phosphine reacts with acrylonitrile under mild conditions to form bis[2-(4- pyridyl)ethyl](2-cyanoethyl)phosphine which is readily...     

Reactions of isoquinoline derivatives with pyridinium salts yielding 4-naphthylpyridines

Regiospecific introduction of the 2-naphthyl residue into position 4 of the pyridine ring occurs in the reactions of isoquinolinium salts with 4-methylpyridinium salts through the intermolecular transformation of the isoquinoline bicyclic system involving the methyl group of the pyridinium salt. The reaction occurs under the action of methylammonium sulfite in an aqueous medium on heating. This method provides ring transformation not only for isoquinolinium salts but even for unsubstituted isoquinoline.