Methanesulfonic Acid → Safinamide Mesylate

Participants

Reaction Conditions

Reaction Steps

A mixture of (S)-2[4-(3-fluorobenzyloxy)benzylamino]propanamide (1.50 g, 4.96 mmol) and ethyl acetate (40.2 mL) is heated to 50° C. until a clear solution is obtained. Methanesulfonic acid (0.53 g, 5.51 mmol) is added under stirring in 15 minutes to the solution and the resulting heterogeneous mixture is cooled under stirring to 20° C. in 90 minutes. After 30 minutes at 20° C. the solid is collected by filtration, washed with ethyl acetate (6 mL) and dried at 50° C. at reduced pressure for 15 hrs to provide (S)-2[4-(3-fluorobenzyloxy)benzylamino]propanamide methanesulfonate (Ic) as a white solid in a 96.1% yield. The product has HPLC purity 98.6 (area %, see Example 17A) and a content of (S)-2-[3-(3-fluorobenzyl)-4-(3-fluorobenzyloxy)-benzylamino]propanamide methanesulfonate (IIc) of 0.10% by weight determined by HPLC (see Example 17B).

Provenance & Evidence