Ethyl 2,4-dioxovalerate → Ethyl 1-(4-fluorophenyl)-3-methyl-1H-pyrazole-5-carboxylate

Participants

Reaction Steps

To ethanol (30 ml) were added 4-fluorophenylhydrazine (5 g) and ethyl 2,4-dioxovalerate (10.6 g) and the mixture was refluxed for 3 h. The solvent was evaporated under reduced pressure and the obtained residue was purified by silica gel column chromatography (mobile phase: chloroform) to give ethyl 1-(4-fluorophenyl)-3-methylpyrazole-5-carboxylate (2 g) and ethyl 1-(4-fluorophenyl)-5-methylpyrazole-3-carboxylate (3 g).

Provenance & Evidence