The reaction of 2-hydrazino-3-methylquinoxaline 1 with trifluoromethyl-β-diketones 2 not only yields the expected 5-trifluoromethyl-5-hydroxy-Δ2-pyrazolines 3a–3f and/or 3- trifluoromethylpyrazoles 4c–4f but also the unexpected products 1, 2, 4-triazolo [4, 3-a] quinoxalines 5a–5f and/or 3 (5)-trifluoromethyl-1H-pyrazoles 6c–6f. Furthermore, the acid- catalyzed dehydration of 5-hydroxypyrazolines 3a–3b resulted in the formation of ...
