Industrial synthesis method of dicamba key intermediate 2,5-dichlorophenol

The invention provides an industrial synthesis method of a dicamba key intermediate 2,5-dichlorophenol. The industrial synthesis method comprises the following steps: firstly, evenly mixing appropriate stabilizer, catalyst and solvent together under a temperature condition not higher than 30 DEG C to obtain a premixed liquid, and then, gradually and dropwise adding a feeding liquid comprising a substrate and an oxidizing agent to perform a synthetic reaction for 3-5 hours, wherein the premixed liquid comprises 1/500-1/300 parts by weight of stabilizer, 1/500-1/50 parts by weight of catalyst and 1-5 parts by weight of solvent; the feeding liquid is prepared from 1 part by weight of substrate 1,4-dichlorobenzene, 1/10-2 parts by weight of oxidizing agent and 2-4 parts by weight of solvent and by virtue of stirring under the condition of 20-30 DEG C for 0.5-1 hour. The method is high in controllability; the utilization efficiency and product yield of the substrate are improved, and the stability of the product yield between various production batches is effectively guaranteed; besides, the industrial synthesis method is low in cost and advantageous for industrial production.