Synthetic method of pyraclonil

The invention discloses a synthetic method of pyraclonil, belonging to the technical field of herbicides. According to the synthetic method, formate, malononitrile, 5-chlorovaleryl chloride, trichloroethylene, hydrazine hydrate and p-toluenesulfonic acid propargyl alcohol ester are taken as main materials, and the pyraclonil is obtained through seven reactions. The synthetic method of the pyraclonil is short in process route, the pyraclonil can be synthesized by only seven reactions, compared with the existing synthetic method, three reactions are eliminated, the yield is greatly improved, and the production cost is lowered.