Sodium Hydroxide → 1-Phenyl-1H-pyrazole-5-carboxylic acid

Participants

Reaction Steps

4.4 g of ethyl 1-phenylpyrazole-5-carboxylate from Example 1 were stirred for 6 hours at room temperature with 10 ml of 16.5% strength aqueous NaOH and 10 ml of ethanol; the ethanol was removed by distillation, the aqueous phase was extracted twice with 10 ml of toluene, and the pH was adjusted to 3 using concentrated HCl. The precipitate was filtered off under suction, washed with a little water and dried: 3.1 g of product of boiling point 182°-183° C. were obtained.

Provenance & Evidence