Hydrazine hydrate (1:1) → 5-Furyl-3-trifluoromethyl-3-hydroxypyrazoline

Participants

Reaction Steps

Part B: 1-(2-cyanophenyl)-5-furyl-3-trifluoromethylpyrazole: To a solution of 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione (2.06 g, 10 mmol) in ethanol (mL) was added hydrazine monohydrate (0.46 g, 10 mmol). The resulting mixture was refluxed for 16 hours and dried under vacuum to give 5-furyl-3-trifluoromethyl-3-hydroxypyrazoline in almost quantitative yield. 1H NMR (CDCl3) δ7.48 (d, J=1.9 Hz, 1H), 6.63 (d, J=3.7 Hz, 1H), 6.47 (dd, J=3.7 Hz, J=1.9 Hz, 1H), 6.16 (s, 1H), 3.48 (d, J=17.9 Hz, 1H), 3.18 (d, J=17.9 Hz, 1H); 19F NMR (CDCl3): δ−81.47; ESMS(+): 221 (M+H, 100).

Provenance & Evidence