Cyanoacetylene and Its Derivatives: XXXIV. Nucleophilic Addition of Tetrazole to Cyanoacetylenes

Nucleophilic addition of tetrazole to 4-hydroxy-4-alkyl-2-alkynonitriles and to 3-phenyl-2-propynonitrile occurred regiospecifically and afforded E-, Z-4-hydroxy-4-methyl-3-tetrazolyl-2-alkenonitriles and 3-tetrazolyl-3-phenyl-2-propenonitrile [20–40°C, 13–50 h, 4–15 wt% MOH (M = Na, K), THF (or DMSO)] in up to 69% yield. The attempt to perform cyclization of the hydroxy-containing adducts into iminodihydrofurans (KOH, ethanol, 23-25°C) resulted in vinyl nucleophilic substitution of the tetrazole moiety by an ethoxy group.     

Cyanoacetylene and Its Derivatives: XXXI. Nucleophilic Addition of 2- and 4-Mercaptopyridines to Cyanacetylenes

Reactions of nucleophilic addition of 2- and 4-mercaptopyridines to 3-phenyl-2-propynonitrile, 4-hydroxy-4-alkyl-2-alkynonitriles, and methyl 2-butynoate (triethylamine, 20-25 or 100°C) give rise to the corresponding S-adducts with Z-configuration (for cyanoethylenes), or to a mixture of E- and Z-isomers in 60:40 ratio for methyl 2-butynoate.     

Investigation of the structure of 2h,6h-2,6-dimethyl-4-amino-1,3,5-dithiazine by IR spectroscopy

It was established by IR spectroscopy that 2H,6H-2,6-dimethyl-4-amino-1,3,5-di-thiazine exists in the amino form in carbon tetrachloride at low concentrations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1050–1053, August, 1981.     

Cyanoacetylenes in a reaction with benzoxazole-2-thione and benzoxazol-2-one

The reaction of benzoxazole-2-thione and benzoxazol-2-one with substituted cyanoacetylenes was studied. 2-[(3-Phenyl-2-propenenitrile)thio]benzoxazole was obtained by the reaction of benzoxazole-2-thione with phenylcyanoacetylene. Benzoxazol-2-one with phenylcyanoacetylene and a tertiary cyanoacetylenic alcohol gave the corresponding N-adducts.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1390–1391, June, 1990.     

Synthesis of substituted 1,3-thiazinoazoles

Substituted 1,3-thiazinoazoles were obtained by treating benzimidazole-2-thione, 4,5-diphenylimidazole-2-thione, and 1,2,4-triazole-3-thione with tertiary cyanoacetylenic alcohols and their acetals in the presence of lithium hydroxide. Treatment of the 1,3-thiazinobenzimidazoles with base destroyed the thiazino ring forming benzimidazol-2-one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1412–1415, October, 1986.     

Reaction of 1,2,4-triazole-3-thiones with 1-chloro-2,3-epoxypropane

Addition of 1-chloro-2,3-epoxypropane to 1,2,4-triazole-3-thiones depending on the ratio of the reactants leads to the formation of 3-(1-chloro-2-hydroxypropyl)-3-(1-chloro-2-hydroxypropylthio)-1,2,4-triazoles. 3-Hydroxy-1,2,4-triazolo[2,3-b] tetrahydro-1,3-triazines have been synthesized by intramolecular cyclization of the monoadducts.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 271–274, February, 1987     

Synthesis and properties of vinyl ethers of 3,4-di(hydroxymethyl)-1,2,5-oxadiazole

The direct vinylation of 3,4-di(hydroxymethyl)-1,2,5-oxadiazole by acetylene was accomplished for the first time; its mono- and divinyl ethers were synthesized in the presence of cadmium acetate. The physicochemical and spectral properties and conformational structure of the synthesized compounds were studied. It was shown that the s-trans-trans-conformation is the most profitable for the divinyl ether of 3,4-di(hydroxymethyl)-1,2,5-oxadiazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1044–1047, August, 1984.     

Acylation of 2H,6H-2,6-dimethyl-4-amino-1,3,5-dithiazine and tautomerism of the reaction products

The acylation of 2H,6H-2,6-dimethyl-4-amino-1,3,5-dithiazine with the chlorides and anhydrides of saturated carboxylic and sulfonic acids leads to N-monoacyl derivatives of dithiazine in 85–96% yields. It was established by IR and UV spectroscopy that 2H,6H-2,6-dimethyl-4-acylamino-1,3,5-dithiazines with donor substituents exist primarily in the amino form and that the equilibrium is shifted to favor the imino form for compounds with acceptor substituents to a greater degree in solutions than in the crystalline state.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 622–626, May, 1982.