Hydrochloric Acid → 5-(4-Chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of the ester 3a (1.0 g, 2.44 mmol) in methanol (25 mL) was added potassium hydroxide (1.0 g, 17.86 mmol) in one portion. The resulting mixture was heated at 60° C. for 4 h. The reaction mixture was then poured into ice water, and the pH of the mixture was adjusted to acidic with addition of 10% hydrochloric acid. The precipitate formed was collected by filtration, washed with water, and dried under vacuum to give carboxylic acid 4a (0.88 g, 94%) as a white solid.

Provenance & Evidence