Reactions of 1-Methyl-1H-1, 2, 4-triazolium 4-Imine and 4-Acylimines with Acetylenic Esters

Abstract

Reaction of 4-amino-1-methyl-1H-1, 2, 4-triazolium iodide with dimethyl acetylenedicarboxylate or methyl propiolate in the presence of alkali followed by heating with water gave methyl 1H-pyrazole-4-carboxylates in low yields, and reaction of 4-acylimino-1-methyl-1H-1, 2, 4-triazolium betaines with methyl propiolate afforded 5-substituted 1-methyl-1H-1, 2, 4-triazoles.