Hydrochloric Acid → Pantoprazole

Participants

Reaction Conditions

Reaction Steps

A 1 L flat bottom flask equipped with a stirrer is charged with acetonitrile (0.6 L). Under mixing compound VI (200 g) is added, followed by water (0.2 L), and NaOH pellets (88 g, 4.0 eq.). The flask is cooled to 5° C. Aqueous 9.4% active NaOCl (540 g, d=1.16, 1.25 eq.) is added dropwise over 40 min. The two-phase mixture is then stirred at room temperature for 40 min at 10° C. Solid Na2S2O5 (6.6 g) is then added, and the mixture is stirred for another 0.5 h. The work up is finished by adjusting the pH to 8.5 with 32% HCl. A precipitate forms in the reaction mixture and is separated by filtration, washed with water, and dried to obtain pantoprazole (137.8 g, yield 66%) containing 0.02% sulfone and 0.01% compound VI within the limit of UV detection.

Provenance & Evidence