Hydrochloric Acid → Paroxetine HCl Ethanol

Participants

Reaction Steps

The paroxetine base can be obtained according to the procedure of U.S. Pat. No. 4,007,196 to Christensen et al. Absolute ethanol is added in an amount sufficient to dissolve the paroxetine base, the molar ratio of paroxetine base to absolute ethanol preferably being in the range of about 10% v/v to about 15% w/v. A solution of hydrochloric acid in absolute ethanol preferably in the range of about 10% v/v to about 30% v/v, usually about 22% v/v, is added to the paroxetine base solution and stirred at ambient temperature and pressure for a time period sufficient to produce paroxetine hydrochloride salt. The preferred molar ratio of paroxetine base to hydrochloric acid is in the range of about 1:1 to about 1:10. The reaction temperature is preferably in the range of about 15 degrees Celsius to about 40 degrees Celsius along with a preferred reaction time in the range of about 10 minutes to about 40 minutes. The resulting solution is then dried by rotary evaporation or spray drying to obtain the desired amorphous paroxetine hydrochloride-ethanol composition. The drying time preferably ranges from about 8 hours to about 72 hours. The amount of ethanol present in the final product relative to paroxetine hydrochloride is not more than about 10 weight percent, more preferably in the range of about 1 to about 4 weight percent.

Provenance & Evidence