1,4-Diacyl-3-acylamino-5-aryl-4,5-dihydro-1H-1,2,4-triazoles: Ring Closure Products of Aromatic Carbaldehyde (Diaminomethylene) Hydrazones with Acylating Agents

Article abstract of DOI:10.1007/BF00807164

Treatment of aromatic carbaldehyde (diaminomethylene)hydrazones 1 with hot acetic anhydride or benzoyl chloride affords 1,4-diacyl-3-acylamino-5-aryl-4,5-dihydro-1H-1,2,4-triazoles 2.In contrast, a new type of O,N-acetal with an 1,2,4-triazole substructure (3) is obtained from 4-pyridine-carbaldehyde(diaminomethylene)hydrazone (1i) by using a similar reaction procedure.The structures of all novel compounds were confirmed by spectroscopic data (1H and 13C NMR, MS, IR); some representative compounds were also studied by X-ray analysis. - Keywords: 1,2,4-Triazolines; (Diaminomethylene)hydrazones; X-Ray analysis; NMR-spectroscopy