Yield:1028843-04-0 46.3%

Reaction Conditions:

with methanesulfonic acid;hydrazine hydrate in ethanol;Reflux;

Steps:

XVII

Method XVII3-(2-methylfuran-3-yl)-lH-pyrazol- -amineHydrazine hydrate (0.244 mL, 5.03 mmol) was added to a solution of 3-(2-methylfuran-3- yl)-3-oxopropanenitrile (0.75 g, 5.03 mmol) and methanesulfonic acid (0.033 mL, 0.50 mmol) in ethanol (25 mL). The reaction mixture obtained was stirred at reflux over night and solvent was evaporated. The crude product was purified by flash silicachromatoghrapy hepatan/ethylacetate to give 3-(2-methylfuran-3-yl)-lH-pyrazol-5-amine (0.380 g, 46.3 %).1H NMR (399.988 MHz, CDC1₃) δ 7.31 (1H, d), 6.55 (1H, d), 5.69 (1H, s), 2.45 (3H, s)

References:

WO2011/114148,2011,A1 Location in patent:Page/Page column 90-91