5-Phenyl-1H-pyrazole-3-carboxylic acid methyl ester

20577-73-5

56426-35-8

General procedure for the synthesis of methyl 5-phenylpyrazole-3-carboxylate from methyl 2,4-dioxo-4-phenylbutanoate: methyl 2,4-dioxo-4-phenylbutanoate (470 mg, 2.28 mmol) was dissolved in acetic acid (5 mL), followed by the addition of hydrazine hydrate (122 μL, 2.51 mmol). The reaction mixture was heated at reflux for 2 h at 118 °C. Upon completion of the reaction, the mixture was concentrated under vacuum to afford methyl 5-phenylpyrazole-3-carboxylate (320 mg, 69% yield), the product was a yellow solid.LCMS analysis result: ES+ 203.0 [MH]+.