Reactions of 4-oxo-1,3-benzoxazinium perchlorates with guanidines

Condensation of 2-methyl-4-oxo-1,3-benzoxazinium perchlorate with various aromatic and heterocyclic aldehydes provided previously unknown arylvinyl-and hetarylvinyl-substituted salts whose recyclization under treatment with guanidine resulted in formerly undescribed 1,3,5-triazines. The reaction of perchlorates obtained with guanidinebenzoxazole led to the formation of bishetarylamines, with guanidinebenzimidazole formed triazinebenzimidazoles, the cyanoguanidine reacted with 4-oxo-1,3-benzoxazinium perchlorates to give cyanamides.     

Recyclization of 4-oxo-1,3-benzoxazinium perchlorates to 4-substituted 5-(o-hydroxyphenyl)-1,2,4-oxadiazolium salts

Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–281, February, 1992.     

Condensation of 2-alkyl-4-oxo-1,3-benzoxazinium salts with carbonyl compounds and their heteroanalogs

A method is proposed for the synthesis of 2-(-dimethylaminovinyl)-4-oxo-1,3-benzoxazinium salts and dimethyl (4-oxo-3H-1,3-benzoxazine-2-methylene) sulfonium salts by condensation of 2-alkylbenzoxazinonium salts with dimethylformamide and dimethyl sulfoxide.Translated from Khimiya Geterotsiklichesikikh Soedinenii, No. 3, pp. 328–331, March, 1977.     

synthesis and some transformations of 4-oxo-2-(β-ethoxyvinyl)-4H-1,3-benzoxazinium salts

A method was developed for the synthesis of 4-oxo-(-ethoxyvinyl)-4H-1,3-benzoxazinium salts by condensation of oxo-2-alkylbenzoxazinium salts by condensation of oxo-2-alkylbenzoxazinium salts with ethyl orthoformate. During hydrolysis and aminolysis, attack of the nucleophile is directed to the -carbon atom of the benzoxazinium salts. The previously unknown 2-formylmethylene-4-oxo-3,4-dihydro-2H-1,3-benzoxazines and their nitrogen derivatives were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 322–327, March, 1977.     

Reactions of 3-imidazolines with diborane and sodium borohydride

Conclusions 3-Imidazoline derivatives, when treated with NaBH₄ in the presence of BF₃ etherate, form adducts with borane, oxidation of which yields stable nitroxyl radicals. On treatment with methanol in the presence of base, the paramagnetic adducts are reduced to the corresponding imidazolidinoxyl derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2337–2342, October, 1985.     

Synthesis of 4-alkylthio-2-(o-hydroxyphenyl)-1,3,5-triazines by recyclization of 4-oxo-1,3-benzoxazine perchlorates

A method has been developed for synthesis of 4-alkylthio-2-(o-hydroxyphenyl)-1,3,5-triazines by treatment of 4-oxo-1,3-benzoxazine perchlorates with S-methyl, benzyl, and allyl-isothioureas.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1658–1661, December, 1989.     

Reduction of 4H-imidazole N-oxides with sodium borohydride

The reduction of derivatives of 4H-imidazole N-oxides with sodium borohydride leads, depending on the presence and position of an N-oxide group, to 1-hydroxyimidazoline or imidazolidine derivatives. Under the same conditions 4H-imidazole N,N-dioxides form 1,3-dihydroxyimidazolidines. The reduction of 1-hydroxy-2,4,5,5-tetramethyl-3-imidazoline 3-oxide leads to N-(3-oximino-2-methyl-2-butyl) ethylhydroxylamine. It was observed by UV spectroscopy that 1-hydroxy-2-imidazolines exist in a tautomeric equilibrium with 2-imidazoline 3-oxides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1557–1561, November, 1976.     

Reactions of 10-telluroniaanthracene perchlorates with nucleophiles

10-Telluroniaanthracene perchlorates react with nucleophiles (X^–=halide, hydroxide, methoxide) via intermediate free telluroxanthyl radicals. With 9-aryl-10-telluroniaanthracene perchlorates, high yields of 9-aryl-9-X-telluroxanthenes are obtained, but with 10-telluroniaanthracene the principal product is 9,9-bis(telluroxathenyl) as a result of rapid competitive dimerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–695, May, 1989.     

Preparation of 1,3-dioxanium perchlorates

2,4,4,6,6-Substituted 1,3-dioxanium perchlorates were obtained by acylation of ditertiary 1,3-diols with carboxylic acid anhydrides in the presence of 70% perchloric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 169–172, February, 1976.     

Synthesis of substituted 1,3-thiazinium perchlorates

Substituted 1,3-thiazinium perchlorates were synthesized by the reaction of -acetylenic ketones with thiobenzamide in acetic acid in the presence of perchloric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 705–708, May, 1988.     

Reactions of 1,3-dihalopropan-2-ones with sodium quinoline-8-thiolate

Mechanochemical reaction of sodium quinoline-8-thiolate with 1,3-dichloropropan-2-one gave 1-chloro-3-(quinolin-8-ylsulfanyl)propan-2-one. 1,3-Bis(quinolin-8-ylsulfanyl)propan-2-one was formed in the reaction of the same reagents in methanol solution. Mechanically activated reaction of sodium quinoline-8-thiolate with 1,3-diiodopropan-2-one resulted in the formation of 9,20-dioxo-8,9,10,19,20,21-hexahydro-[1,11,4,8]dithiadiazacyclotetradecino[2,3,4-ij: 10,9,8-i′j′]diquinoline-18,22-diium diiodide.     

Reactions of 4-hydrazinoquinazoline with derivatives of 1,3-cyclanediones

In reactions of 4-hydrazinoquinazoline with 2 formyl- and 2-acetyldimedones, 2 formyl-1,3-indandione, dehydroacetic acid, and 2, 2-dimethyl-5-ethoxymethylene-1, 3-dioxane-4, 6-dione, the corresponding hydrazinomethylene and 1-hydrazinoethylidene derivatives have been obtained. Attempts to convert the 2-hydrazinomethylene- and 2-(1-hydrazinoethylidene)dimedones to indazole derivatives were unsuccessful. In reactions of 4-hydrazinoquinazoline with 2-cyano-3-ethoxy-5,5-dimethylcyclohex-2-en-1-one, 3-hydrazino derivatives were obtained; with 2-amino-5-oxo-7, 7-dimethyl-5, 6, 7, 8-tetrahydroquinazoline and 1 phenyl-4,5-dioxo-6, 6-dimethyl-4, 5, 6, 7-tetrahydroindazole, the corresponding 5(4-quinazolylhydrazino) derivatives were obtained.     

Substituent effects on 13C chemical shifts of alkyl-substituted 4-oxo-1,3-dioxolanes and 5-oxo-1,3-oxathiolanes

The 13C NMR chemical shifts for 4-oxo-1,3-dioxolane (1) and its all methyl-substituted derivatives (2-10) as well as for 5-oxo-1,3-oxathiolane (11) and its nine alkyl-substituted derivatives (12-20) are reported. The magnitude and variety of the substituent effects are in accordance with the envelope conformations in which the oxygen or sulfur atom locates at the tip of the envelope as postulated on the basis of earlier data.     

Reactions of 4-chloro-6-oxo-2,3-dihydro-5-azabenzofurans with amines

The reaction of 7-nitro- and 7-unsubstituted 4-chloro-6-oxo-2,3-dihydro-5-azabenzofurans with primary and secondary amines proceeds with substitution of the chlorine atoms by amine residues and with recyclization of the compounds to 5- and 7-azaindoline derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No, 10, pp. 1311–1313, October, 1973.We thank Yu. N. Sheinker, E. M. Peresleni, L. M. Alekseeva, N. A. Zosimova, and Yu. I. Pomerantsev for their assistance in conducting the spectral investigations.