Phenylhydrazine → 3-Cyclobutyl-1-phenyl-1H-pyrazol-5-amine

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of 3-cyclobutyl-3-oxopropanenitrile (24.6 g, 0.20 mol) and phenylhydrazine (23.62 g, 0.20 mol) in ethanol (200 mL) was heated at 90° C. for 15 h. The reaction mixture was quenched with water and extracted with dichloromethane. The combined dichloromethane layers were dried over magnesium sulfate, concentrated under reduced pressure to give a solid which was triturated with a mixture of 10% petroleum ether in ethyl acetate, followed by trituration with diethyl ether to afford 3-cyclobutyl-1-phenyl-1H-pyrazol-5-amine (18.20 g, 43% over two steps) as a colorless solid. 1H NMR (400 MHz, DMSO-d6) δ 7.55-7.57 (m, 2H), 7.42-7.46 (m, 2H), 7.26 (m, 1H), 5.40 (s, 1H), 5.25 (s, 2H), 3.33 (m, 1H), 2.05-2.50 (m, 4H), 1.82-1.96 (m, 2H).

Provenance & Evidence