T. E. Glotova

Synthesis of 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazepines and 4-amino-3-acylvinylthio-1,2,4-triazoles by reaction o acylacetylenes with 4-amino-3-mercapto-1,2,4-triazole

Abstract1,2,4-Triazolo[3,4-b]-1,3,4-thiadiazepines have been prepared by treating α-acetylenic ketones with 4-amino-3-mercapto-1,2,4-triazole in glacial acetic acid. Terminal acetylenic ketones react with the triazole to form 4-amino-3-acylvinylthio-1,2,4-triazoles. Heating the latter with hydrazine hydrate in alcohol yields substituted pyrazoles.

Synthesis of 1,3,4-thiadiazole derivatives by the reaction of thiosemicarbazide or its 1- or 4-substituted derivatives with some 1-bromo-2-acylacetylenes

The reaction of thiosemicarbazide, 4-methyl-, 4-phenyl-, or 1-phenylthiosemicarbazides with 1-bromo-2-benzoyl(thenoyl-2)acetylenes in acetonitrile or glacial acetic acid yielded 2-acylmethylene- and 2-acylmethyl-5-amino-1,3,4-thiadiazoles. Heating of the latter in alcohol or aqueous alcohol gave the free bases.

Synthesis of 1,3,4-thiazole derivatives by the reaction of thiobenzhydrazide with some acylacetylenes

Abstract2-Acylmethyl-5-phenyl- and 3-acylvinyl-2-acylmethyl-5-phenyl-1,3,4-thiadiazol-4-ines were obtained by the reaction of terminal α-acetylenic ketones with thiobenzhydrazide. Substituted acetylenic ketones react with thiobenzhydrazide in alcohol to give N,S-bis(acylvinyl)thiobenzhydrazides.

Synthesis of substituted 1,3-thiazinium perchlorates

Substituted 1,3-thiazinium perchlorates were synthesized by the reaction of α-acetylenic ketones with thiobenzamide in acetic acid in the presence of perchloric acid.

Reaction of 1-acyl-2-phenylacetylenes with thiosemicarbazide

ConclusionsThe reaction of 1-acyl-2-phenylacetylenes with thiosemicarbazide in methanol at 60‡C gives 2-amino-7-hydroxy-6,7-dihydro-1,3,4-thiadiazepines which, upon heating in -vacuum fragment with the formation of 3,5-disubstituted pyrazoles.