Sodium Hydroxide → 2-(4-fluorophenyl)-6-methyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole-3-carboxylic acid

Participants

Reaction Steps

36.8 ml (73.6 mmol) of a 2 M aqueous NaOH solution are added to a solution of 7.0 g (25.5 mmol) of methyl 2-(4-fluorophenyl)-6-methyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole-3-carboxylate in 50 ml of methanol, and the mixture is stirred for 3 h. The reaction mixture is concentrated under reduced pressure, ethyl acetate/1 M hydrochloric acid is added, the organic phase is separated off and the aqueous phase is extracted with 3×100 ml of ethyl acetate. The combined organic phases are dried over Na2SO4 and freed from the solvent under reduced pressure. The 2-(4-fluorophenyl)-6-methyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole-3-carboxylic acid obtained (5.9 g) is reacted further without further purification.

Provenance & Evidence