Ethanol → Ethyl 3-(4-fluorophenyl)-1h-pyrazole-5-carboxylate

Participants

Reaction Steps

A mixture of ethyl 3-(4-fluorobenzoyl)pyruvate (11.3 g, 47.4 mmol), hydrazine monohydrate (2.50 g, 50.0 mmol) and ethanol (50 mL) was heated under reflux for 1 hr. The reaction mixture was cooled and poured into water. The precipitated solid was collected by filtration, washed with water, and dried to give the title compound (11.0 g, quantitative) as colorless crystals. 1H NMR (CDCl3) δ: 1.41 (3H, t, J=7.2 Hz), 4.41 (2H, q, J=7.2 Hz), 7.05-7.18 (3H, m), 7.76 (2H, dd, J=8.2, 5.4 Hz), 11.21 (1H, s).

Provenance & Evidence