Hydrazine hydrate (1:1) → 4-(1H-Pyrazol-1-yl)benzohydrazide

Participants

Reaction Steps

To a solution of ethyl 4-(1H-pyrazol-1-yl)benzoate (711 mg, 3.29 mmol) in absolute EtOH (50 mL) was added hydrazine monohydrate (1.6 mL, 32.9 mmol) at room temperature. The reaction mixture was heated to reflux and stirred for 6 d, then concentrated under reduced pressure. The residue was suspended in H2O (30 mL), filtered, washed with H2O (2×20 mL) and EtOH (2×20 mL) to provide the title compound as an off white solid (101 mg, 15%): 1H NMR (400 MHz, CDCl3, δ in ppm) 9.84 (s, 1H), 8.62-8.59 (m, 1H), 7.98-7.90 (m, 4H), 7.81-7.78 (m, 1H), 6.61-6.57 (m, 1H), 4.51 (br d, J=3.3 Hz, 2H).

Provenance & Evidence