Hydrochloric Acid → Zofran

Participants

Reaction Steps

The crude ondansetron from Example 4 (190 grams; 0.65 mol) was suspended in a mixture of isopropanol (1.2 L) and water (0.24 L). Concentrated hydrochloric acid (32% (w/w)) was added until the pH of the mixture was about 1-2 (about 70 mL). The solution was heated to reflux temperature for one hour and then cooled to room temperature. The precipitated crystals were collected by filtration, and dried to provide 117 grams (0.32 mol; 49% yield) of crude ondansetron hydrochloride dihydrate. The purity was determined to be about 98-99% by HPLC.

Provenance & Evidence