Sodium Hydroxide → Fesoterodine fumarate

Participants

Reaction Conditions

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 methyl ethyl ketone (170 ml) is added at 25° C. to 30° C. and stirred for 10 minutes and then heated to 80° C. Fumaric acid (21.5 g) was added to the resulting mass, stirred for 1 hour at 80° C. followed by the drop wise addition of cyclohexanc (70 ml) at 80° C. and stirred for 1 hour. The resulting mass was slowly cooled to 25° C. to 30° C. and stirred for 12 hours at the same temperature. The resulting mass was then cooled to 0° C. to 5° C. and stirred for 12 hours at 0° C. to 5° C. The separated solid was filtered, washed with the mixture of cyclohexane (135 ml) and methyl ethyl ketone (15 ml), and then dried under vacuum at 45° C. to 50° C. to afford Fesoterodine Fumarate (70 g) (Purity by HPLC: 99.95%).

Provenance & Evidence