Process for the preparation of 1,2,4-triazole
AssigneeHoechst Aktiengesellschaft
InventorsHarald Knorr, Thomas Maier, Hilmar Mildenberger, Helmut Korbanka
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Abstract
1,2,4-triazole is obtained by cyclization of N,N'-diformylhydrazine with ammonia in the presence of formamide. The amount of ammonia required is either formed in situ from thermally decomposable ammonium salts, or supplied by feeding in gaseous ammonia. Simultaneously, the water of reaction is constantly distilled off from the system.
Claims4
A process for the preparation of 1,2,4-triazole by cyclization of N,N'-diformylhydrazine in the presence of ammonia at elevated temperature, which comprises supplying the amount of ammonia required either (a) by forming it in situ from ammonium carbonate or ammonium hydrogen carbonate with heating to 150.degree.-250.degree. C., or (b) introducing gaseous ammonia into the N,N'-diformylhydrazine under the same conditions, while operating in both cases without pressure and in formamide as solvent, and constantly distilling off the water formed.
Dependencies are inferred from the claim text.