Abstract: The present invention relates to a method for synthesizing prasugrel, comprising the following steps: converting o-fluorobenzyl cyclopropyl ketone into ?-cyclopropylcarbonyl-2-fluorobenzyl halide (compound 2) using dibromohydantoinhydantoin as halogenation reagent and acetic acid as solvent, then 2-oxo-4,5,6,7-tetrahydrothieno[3,2-c]pyridine p-toluenesulfonate (compound 4) is obtained with high yield by a concerted catalysis using a phase transfer catalyst and an inorganic salt, then is condensed and acylated to obtain prasugrel as a gum. The present invention also provides a method for purifying prasugrel comprising crystallizing using alcohols as a crystallization solvent to obtain prasugrel crystals with a high purity.

Abstract: The present invention relates to a method for synthesizing prasugrel, comprising, the following steps: converting o-fluorobenzyl cyclopropyl ketone into ?-cyclopropylcarbonyl-2-fluorobenzyl halide (compound 2) using dibromohydantoinhydantoin as halogenation reagent and acetic acid as solvent, then 2-oxo-4,5,6,7-tetrahydrothieno[3,2-c]pyridine p-toluenesulfonate (compound 4) is obtained with high yield by a concerted catalysis using a phase transfer catalyst and an inorganic salt, then is condensed and acylated to obtain prasugrel as a gum. The present invention also provides a method for purifying prasugrel comprising crystallizing using alcohols as a crystallization solvent to obtain prasugrel crystals with a high purity.