Synthesis of 4H-1, 3-oxazin-4-onium salts

Chemistry of Heterocyclic Compounds -     

2-Styryl-4H-1,3-benzoxazin-4-onium salts

A method was developed for the synthesis of 2-styryl-4H-1,3-benzoxazin-4-onium salts by condensation of 2-alkylbenzoxazinonium salts with aromatic aldehydes. It is shown that these same compounds are formed by acid condensation of salicylamides, salicylnitrile, or salicylaldoxime with aromatic aldehydes in acetic anhydride. The hydrolysis and alcoholysis of the synthesized salts were studied.     

Synthesis of 4H-1,3-benzoxazin-4-onium salts and 4-H-1,3-benzoxazin-4-ones

Salicylamide and its substituted derivatives react with aliphatic carboxylic acid anhydrides and perchloric acid to give 4H-1,3-benzoxazin-4-onium salts. These same compounds were obtained by acidic cyclization of O- and N-acylsalicylamides. The synthesized salts are converted to 2-substituted 4H-1,3-benzoxazin-4-ones by the action of triethylamine and are hydrolyzed by water to N-acylsalicylamides. The probable reaction scheme is examined.     

Molecular complexes ofsym-octahydro-1-chalcogenaanthracene salts with aromatic compounds

Complexes ofsym-octahydro-10-chalogenaanthracene perchlorates with aromatic hydrocarbons, di- and triatomic phenols, naphthols, and aromatic amines can be readily separated in the solid state. Complex formation is clearly shown to lower the oxidative power of the heteroaromatic cations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 27–32, January, 1995.Deceased     

Acylation of salicylnitrile and salicylaldoxime as a method for the synthesis of 4H-1,3-benzoxazin-4-onium salts

Methods were developed for the synthesis of 4H-1,3-benzoxazin-4-onium salts by acylation of salicylnitrile and salicylaldoxime with acid anhydrides and chlorides are acids in the presence of perchloric acid or tin perchlorate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 742–744, June, 1976.     

Reaction of 1-alkylthioisoquinolinium salts with active methylene compounds

2-Alkyl-1-alkylthioisoquinolinium salts were readily prepared from 2-alkyl-1(2H)-isoquinolones via 2-alkyl1(2H)-thioisoquinolones in two steps. Under mild conditions, the reaction of 2-alkyl-1-alkylthioisoquinolinium salts with active methylene compounds in the presence of sodium hydride afforded 2-alkyl-1-(substituted methylene)iso-quinolines in good yields. Pyrrolo[2,1-a]isoquinolines were synthesized by the cyclization of 2-benzyl-1-(substituted methylene)isoquinolines using acetic anhydride.     

3-phenyl-2H-1,4-benzoxazine-4-oxides—I : Synthesis and reduction

The title compounds were prepared by reductive cyclisation of o-nitro-phenoxy-acetophenones and characterized through a cycloadduct with acrylonitrile. Reduction of the N-oxides leads to the corresponding hydroxylamines that are highly unstable and can be transformed into the corresponding nitroxides by a variety of oxidation agents, including air. Previously unknown o-nitro-phenoxy-acetophenones were synthesized as starting materials for cyclisation reactions.     

Reaction of benzo-1,2,3-dithiazolium salts with aromatic amines

The character of a displaceable group depends substantially on the rate of reaction of substituted 6-chloro and 6-methoxy derivatives of benzo-1,2,3-dithiazolium salts, which gives the corresponding 6-phenylaminobenzo-1,2,3-dithiazolium salts. In 4,6-disubstituted benzo-1,2,3-dithiazolium salts, an aniline residue displaces only the substituent in the 6 position.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 183–185, February, 1976.     

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     

Reaction of 2-dialkyl-5-formylfurans, -thiophenes,and-selenophenes with aromatic diazonium salts

The reaction of 2-dialkylamino-5-formylfurans, -thiophenes, and -selenophenes with diazonium salts gives azo dyes with elimination of the aldehyde group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1325–1326, October, 1974.