Hydrochloric Acid → Doxazosin Monohydrochloride

Participants

Reaction Conditions

Reaction Steps

Doxazosin base (0.110 mol; 49.61 g) was charged in acetone (750 ml) and stirred at 25° C. to obtain slurry. On cooling the slurry to 10-15° C., hydrochloric acid solution was added till the pH was 2-3. The contents were stirred for 10-15 min at 10-15° C. and then stirring continued at 25° C. for 2 hr. The solid obtained was filtered, washed with acetone and dried at 50-55° C. to obtain solid product. The solid was purified by refluxing with methanol (600 ml) for 1 hr. The slurry was cooled to room temperature, filtered, washed with methanol and then dried at 60° C. under reduced pressure to obtain 51 g of pure doxazosin hydrochloride (HPLC purity −99.77%).

Provenance & Evidence