Ethanol → 1-((4-methoxyphenyl)methyl)-1H-pyrazol-5-amine

Participants

Reaction Conditions

Reaction Steps

Hydrazine (10 mL, 320 mmol) was added over 10 min. to a vigorously stirred solution of 2-propenenitrile (22.3 mL, 339 mmol) in EtOH (100 mL), which was cooled in an ice-water bath to below 20° C. After stirring for 20 h, the reaction mixture was cooled in an ice-water bath, and 4-methoxybenzaldehyde (41.1 mL, 338 mmol) was added slowly. The reaction mixture was stirred at room temperature for 60 h. The solution was concentrated under reduced pressure and the residue was dissolved in isopropyl alcohol (100 mL). NaOH (7 g, 200 mmol) was added and the resulting mixture was heated at 120° C. for 2 h. The solution was concentrated under reduced pressure and the residue was diluted with water and EtOAc. The layers were separated and the aqueous layer was then extracted with further EtOAc. The combined organic extract was washed with 1 M HCl. The HCl layers were combined and the pH was adjusted to 14 using NaOH. The resulting slurry was extracted with DCM. The DCM layers were dried over Na2SO4, filtered and concentrated under reduced pressure to afford 21 g of the sub-title compound (30%). LCMS calc. for C11H14N3O (M+H)+: m/z=204.1. Found: 204.2.

Provenance & Evidence