Diisopropyl Ether → Fesoterodine fumarate

Participants

Reaction Steps

Fesoterodine 2-Chloro-mandelate (85 g), water (425 ml) and MDC (225 ml) were added to a four-neck two liter round bottom flask at 25° C. to 35° C. The reaction mass is cooled to 0° C. to 5° C. The pH was adjusted to 10 to 10.5 by addition of 10% sodium hydroxide solution at 0° C. to 5° C. Temperature of the reaction mass is raised to 25° C. to 35° C. and maintained for 30 minutes. The layers were settled and separated. Further, to the MDC layer water (255 ml) is added at 25° C. to 35° C. and further cooled to 0° C. to 5° C. and pH was adjusted to 10 to 10.5 by addition of 10% sodium hydroxide solution. The temperature of the reaction mass is raised to 25° C. to 35° C. and maintained for 30 minutes. The layers were settled and separated. To the MDC layer activated charcoal (4.2 g) is added and stirred for 30 minutes. The resulting mass was filtered and washed with MDC (2×42.5 ml) and to the obtained resulting mass IPA (240 ml) is added at 25° C. to 30° C. and then heated to 50° C. to 55° C. Fumaric acid (17 g) was added to the resulting mass was maintained for 30 minutes and further cooled to 25° C. to 30° C. followed by the addition of diisopropyl ether (840 ml) at 25° C. to 30° C. and maintained for 12 hours. The resulting mass was filtered, washed with diisopropyl ether (2×30 ml) and then dried under vacuum for 24 hours at 45° C. to 50° C. to afford Fesoterodine Fumarate (70 g) (Purity by HPLC: 99.98%).

Provenance & Evidence