Method for preparing industrial safinamide mesylate

The invention relates to a method for preparing industrial safinamide mesylate, and belongs to the technical field of organic synthesis. The method comprises the steps that a compound 3-fluorobenzylchloride and a compound p-hydroxy benzaldehyde react to generate a compound 4-(3-fluorophenyl)benzaldehyde, then the compound 4-(3-fluorophenyl)benzaldehyde and (S)-2-amino methyl propionate hydrochloride are condensed to prepare a compound (S)-2-[4-(3-fluorophenyl)benzylamine]propanamide, the compound (S)-2-[4-(3-fluorophenyl)benzylamine]propanamide is subjected to catalytic hydrogenation reducing with Pd/C, and the product is recrystallized through methylbenzene and then salified with methanesulfonic acid. A new industrial synthesis selection mode is provided, the synthesis mode has the advantages of being easy and convenient to operate, simple in aftertreatment, lower in cost, environmentally friendly and the like, the high-quality target product can be obtained, and industrial production is promoted.