Sulfuric Acid → Clopidogrel Bisulfate

Participants

Reaction Conditions

Reaction Steps

Clopidogrel base (250 gms) was dissolved in n-hexanol (1.25 L) with stirring at 25 to 30° C. Dilute sulfuric acid was added to it at 10 to 15° C. The mixture was stirred at room temperature for 6 hrs and subsequently it was stirred at 22 to 25° C., for 5 hours at high agitation. The reaction mixture was further stirred for 4 hours at room temperature at low agitation. The mixture was then filtered, washed with methyl tert butyl ether (750 ml) and dried at 30 to 35° C. in a drier to get 250 g of Clopidogrel bisulfate salt as crystals. Subsequent analysis confirmed that the crystals were Clopidogrel hydrogen sulfate Form-I.

Provenance & Evidence