The invention belongs to the technical field of medical
chemistry, and particularly relates to an optimal
edaravone synthesis method. The method comprises the following steps in sequence: (1) adding
phenyl hydrazine or
phenylhydrazine hydrochloride serving as an initial
raw material into a container in which water is held under a stirring condition and adjusting the pH value to be 6.0 by taking a proper amount of concentrated
hydrochloric acid or
ammonia water; (2) slowly dropwise adding
ethyl acetoacetate into the solution obtained in the step (1), reacting and discharging heat, adding
sodium hyposulfate after the solution is cooled to
room temperature, heating the solution, performing
reflux reaction for 2-5 hours, stopping heating, stirring, cooling, and performing vacuum
filtration to obtain a light yellow granular
edaravone rough product; and (3) recrystallizing the
edaravone rough product obtained in step (2) by using absolute
ethanol, performing vacuum
filtration and
drying to obtain white crystalline
powder solid, namely an edaravone finished product. The method has the advantages of low cost, high yield and high purity; and the problems existing in the conventional edaravone synthesis process are solved.