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Dibromobenzene can be produced by direct bromination or by diazotization or displacement reaction using the corresponding bromoaniline.

(1) Direct bromination of benzene: benzene is used as a raw material to carry out a substitution reaction with bromine, a Lewis acid is used as a catalyst, and a hydroxyl group-containing solvent is used as a solvent, such as ethanol or acetic acid. It can produce a variety of bromine substituted compounds, adjust the ratio of materials and reaction conditions, so that the reaction is beneficial to the target product, the obtained mixed bromide is debrominated and separated to obtain the desired product, and the remaining by-products can be recycled, which has increased the yield of the target product. .

(2) The bromoaniline corresponding to the amino substituent is used as a raw material by diazotization or displacement, for example, ortho-dibromobenzene can be prepared, and o-bromoaniline can be used as a raw material to carry out diazotization to form o-bromobrominated diazonium. Benzene, the latter is subjected to bromine displacement to obtain o-dibromobenzene. The reaction equation is as follows: the diazotization reaction is carried out in an aqueous solution of about 10 ° C and an excess of sodium nitrite, and the obtained diazotide is injected into boiling cuprous bromide. In the hydrobromic acid solution, water vapor is introduced after the reaction until no oily liquid is distilled off. The lower oil layer of the distillate is separated, washed with concentrated sulfuric acid, washed with water, washed with 5% NaOH aqueous solution, dried with anhydrous calcium chloride, and then distilled, and the fraction of 223-225 ° C is taken as o-dibromobenzene product.