Hydrochloric Acid → 1H-thieno[3,2-c]pyrazole-5-carboxylic acid

Participants

Reaction Steps

To a solution of methyl 1H-thieno[3,2-c]pyrazole-5-carboxylate (F-5) (4.2 g, 18.7 mmol) in MeOH (50 mL) was added a solution of LiOH.H2O (3.1 g, 74.8 mmol) in water (5 mL). The reaction mixture was stirred at room temperature overnight. Then 1N HCl was added to adjust to pH to ˜5, the resulting precipitate was collected and dried to afford the title compound.

Provenance & Evidence