Vy. Sosnovskikh et al., REACTION OF ,3-DIALKYL-6-TRIFLUOROMETHYL-2,3-DIHYDRO-4-PYRONES WITH HYDRAZINE HYDRATE, Russian chemical bulletin, 47(7), 1998, pp. 1365-1368
,3-Dialkyl-2,3-dihydro-6-trifluoromethyl-4-pyrones react with hydrazin
e hydrate to give 2-hydrazino-2-trifluoromethyl-4-tetrahydropyrone hyd
razones. When heated, the latter are transformed into 5)-(2-hydroxyeth
yl)-5(3)-trifluoromethylpyrazoles, while their treatment with HCl in e
ther leads to 3,3-dialkyl-2,3-dihydro-6-trifluoromethyl-4-pyrone azine
s.