Acetic Acid → 4-isopropyl-1H-pyrazol-5-amine

Participants

Reaction Steps

Next, 2-formyl-3-methylbutanenitrile 2 (9.97 g, 90 mmol), hydrazine hydrate (5.68 mL, 117 mmol) and glacial acetic acid (9.02 mL, 158 mmol) were dissolved in EtOH (250 mL) and the mixture was heated under reflux for 16 h. The reaction was then concentrated to approximately one third of the original volume. The residue was diluted with sat. NaHCO3 (100 mL) and the product extracted with CH2Cl2 (3×100 mL). The combined organic fractions were washed with brine, dried over MgSO4 and the solvent was removed in vacuum. Crude 4-isopropyl-1H-pyrazol-5-amine (3) was obtained as a yellow oil (7.17 g, 64%).

Provenance & Evidence