Some novel observations on the reaction of 2-hydrazino-3-methylquinoxaline with trifluoromethyl-β-diketones

The reaction of 2-hyrazino-3-methylquinoxaline 1 with trifluoromethyl-β-diketones 2 in different reaction conditions resulted in the formation of the unexpected products 1,2,4-triazolo[4,3-a]quinoxalines 5 and 3(5)-trifluoromethyl-1H-pyrazoles 6 in addition to the expected products 3-trifluoromethylpyrazoles, 5-hydroxy-5-trifluoromethylpyrazolines and their corresponding dehydrated pyrazoles. Also, formation of unexpected triazolo[4,3-a]quinoxaline 5 takes place during dehydration of hydoxypyrazolines 3 in acidic medium.