Reaction of tetrachloropyrazine with active methylene compounds

When tetrachloropyrazine was allowed to react with the anions formed from diethyl malonate and malonitrile, the normal alkylation took place. When the anions from ethyl acetoacetate and N,N-diethylacetoacetamide were used, alkylation was followed by enolization and ring formation to give furo [2,3-b] pyrazines. The structure proof and reaction of the furo [2,3-b] pyrazines are discussed.     

Reaction of thiopyrylium ion with active methylene compounds

The reaction of 2,4,6-triphenylthiopyrylium ion with several active methylene compounds in the presence of base has been found to yield 2,4,6-triphenylbenzene derivatives. In the case of the reaction of 2,4,6-triphenylthiopyrylium fluoroborate with nitromethane, an alkali treatment gave 2,4,6-triphenylnitrobenzene, and an acid treatment afforded 2,4,6-triphenylbenzene, respectively. From these results, the reaction behaviour of the thiopyrylium ion has been discussed.     

Reaction of 3-azidoisoxazoles with active methylene compounds

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On the reaction of 2-amino-4-thiazoliniminium salts with active methylene compounds

Summary The easily available 2-amino-4-thiazoliniminium salts6 react with different types of active methylene compounds. Whereas 2-amino-4-cyanomethylene-4,5-dihydrothiazoles13 and14 are formed with malononitrile (11) or ethyl cyanoacetate (12) in the presence of bases, acetyl acetone (15) and ethyl acetic acetate (16) afford 2-amino-thiazolo[4,5-b]pyridines21 and22, resp. The structures of the new compounds13, 14, 21 and22 have been elucidated by means of analytical and spectroscopic methods and confirmed by some chemical reactions.

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Reaktion von 2-Amino-4-thiazoliniminium-Salzen mit aktivierten Methylenverbindungen

Zusammenfassung Durch Reaktion der einfach zugänglichen 2-Amino-4-thiazoliniminium-Salze6 mit Malonsäuredinitril (11) oder Cyanessigsäureethylester (12) in Gegenwart von Basen werden die 2-Amino-4-cyanmethylen-4,5-dihydrothiazole13 bzw.14 gebildet, während mit Acetylaceton (15) und Acetessigsäureethylester (16) auf analoge Weise die 2-Aminothiazolo[4,5-b]pyridine21 bzw.22 entstehen. Die Strukturen der neu dargestellten Verbindungen des Typs13, 14, 21 und22 wurden spektroskopisch abgesichert und durch einige Folgereaktionen bestätigt.

     

Reaction of α-keto hydrazonyl bromide with carbanions of some active methylene compounds

Treatment of 1-phenyl-2-bromo-2-arylhydrazonoethanone (VII) with sodium etiolates of 2,4-pentanedione, 1-phenyl-1,3-butanedione, dibenzoylmethane, ethyl benzoylacetate, acetoaceta-nilide, and of benzoylacetanilide in ethanol afforded the substituted pyrazoles, VIII-XIII, respectively. The results show that VII, unlike 1-phenyl-2-bromo-2-hydroximinoethanone (V), is not easily deprotonated by carbanions; and that its reactions with β-diketones, β-keto esters, and β-keto amides follow one and the same mechanism. The structures of the products (VIII-XIII) were inferred from their elemental analyses and spectral data.     

Reaction of 2, 6-dimethylthiapyrone with compounds containing active methyl or methylene groups

The reaction of 2, 6-dimethylthiapyrone with compounds containing active methyl or methylene groups is investigated. Position 4 in the thiapyrone ring is found to react. If the components with active methylene groups are malonodinitrile or cyclic diketomethylene compounds, the methylene groups in the resultant 2, 6-dimethylthiapyrane compounds are still reactive towards electrophilic reagents, a property which is utilized for synthesis of nonionic polymethylene dyes containing thiapyrane rings.     

Indium-catalyzed addition of active methylene compounds to 1-alkynes

An active methylene compound adds to a 1-alkyne in high to quantitative yield upon heating in the presence of 0.05-5 mol % of In(OTf)3 to give an alpha-alkenylated carbonyl compound.     

Acetylenic ketones. I. Reaction of aroylphenylacetylenes with compounds containing an active methylene group

Aroylphenylacetylenes reacted with ethyl phenylacetate and benzyl cyanide in the presence of sodium ethoxide to give 6-aryl-3,4-diphenyl-2H-pyran-2-ones (2) and 4-aroyl-2,3-cis-diphenyl-crotonitriles (11) , respectively. The structure and configuration of the products are based on chemical and spectroscopic evidence.     

Reaction of indol-3(2H)-one derivatives with some active methylene compounds

The reaction of substituted (Z)- and (E)-2-arylmethylideneindolin-3(2H)-ones with malononitrile gave the Micheal addition products which could be cyclised to the corresponding pyrano[3,2-b]indole. Larger molecules such as cyanoacetic acid and ethyl cyanoacetate failed to react.     

Reaction of nitro compounds with iminium salts 1. Nitrovinylation of indoles

Conclusions Iminium salts prepared from indoles, thionyl chloride, and dimethylformamide readily form the corresponding nitrovinyl derivatives by nucleophilic attack on the anion of an aliphatic nitro compound.Translated from Izvestiya Akademiya Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2310–2313, October, 1977.     

Reaction of epoxy compounds with salts of thioacids

Conclusions 1. When the alkali metal salts or the ammonium salts of O,O-dialkyl thiophosphates or O,O-dialkyl dithiophosphates are reacted with epoxy compounds the latter undergo thioepoxidation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 353–358, February, 1971.     

Reaction of haloadamantanes with salts of nitro compounds

Silver and mercury salts of nitro compounds react with bromo- or chloroadamantanes with the formation of products of C- and/or O-alkylation, the ratio of which depends on the structure of the initial reactants. The direct experimental evidence of nitronic esters to be isomerized into nitro derivatives and of their role as intermediates in the formation of the nitro derivatives in the alkylation of nitro compounds has been presented for the first time.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiva Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1798–1803, August, 1992.     

Reaction of some organomercury compounds with diazonium salts

Summary We were the first to replace a mercury atom attached to a saturated carbon atom by the arylazo group. The reaction of the p-nitro- and 2,4-dinitrophenyldiazonium fluoborates with ethyl -bromomercuriphenylacetate and with bromomercurimethyl tert-butyl ketone give the corresponding arylhydrazones in good yields.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1711–1712, September, 1964     

Imidazolium salts as phase transfer catalysts for the dialkylation and cycloalkylation of active methylene compounds

The dialkylation and cycloalkylation reactions of active methylene compounds in the presence of readily available imidazolium salts (ionic liquids) as phase transfer catalysts were performed to afford the respective dialkylated or cycloalkylated products. This method is very efficient for the synthesis of 1,1-disubstituted derivatives and cyclopropane and cyclopentane ring systems in a facile manner.     

Reactions of quaternized imidazo-quinazoline and-pyridopyrimidine with active methylene compounds

Summary Syntheses of 1-methylimidazo[1,2-c]quinazolinium iodide (3) and 1-methylimidazo[2,1-f]pyrido[3,2-d]pyrimidinium iodide (4) are described. These tricyclic compounds react with nucleophiles derived from active methylene compounds to give the corresponding open-chain enamines.

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Reaktionen von quaternisierten Imidazo-Chinazolinen und -Pyridopyrimidinen mit Verbindungen mit reaktiven Methylengruppen

Zusammenfassung Synthesen von 1-Methylimidazo[1,2-c]chinazoliniumjodid (3) und 1-Methylimidazo[2,1-f]pyrido[3,2-d]pyrimidiniumjodid (4) werden beschrieben. Diese tricyclischen Verbindungen reagieren mit einigen Carbanionen aus Verbindungen mit reaktiven Methylengruppen, wobei die offenkettigen Enamine entstehen.

     

2-Benzopyrylium salts. 39. Recyclization of 2-benzopyrylium salts upon reaction with vinyl ethyl ether and compounds with an active methylene group

The reaction of 2-benzopyrylium salts with vinyl ethyl ether, ethyl acetoacetate, malonodinitrile, and nitromethane gives variously substituted naphthalene derivatives. It is proposed that the reaction with vinyl ether proceeds through [4+2] cycloaddition, while the reaction with the compounds with an active methylene group proceeds either through the ANRORC mechanism or through the formation of bridged intermediates, depending on the conditions.For Communication 38, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 315–320, March, 1990.     

Reaction of 1,3,4-thiadiazolo and 1,3,4-triazolo[3,2-c]quinazoline derivatives with active methylene compounds

Fused quinazoline derivatives 1 and 4 react with active methylene compounds and depending on the annelated five-membered ring, two types of transformations have been observed. The 1,3,4-thiadiazolo[3,2-c]quinazoline 1 , underwent the five-membered ring opening reaction to afford the 3,4-dihydroquinazolines 2 in good yields, whereas the 1,3,4-triazolo[3,2-c]quinazoline 4 underwent nucleophilic attack at 2-position of the quinazoline ring to yield the corresponding 1,2,4-triazoles 5 .