Production method of 1-bromine-2-butyne

The invention relates to a production method of 1-bromine-2-butyne. The production method comprises the following steps of enabling ethyl bromide and metal magnesium to be subjected to a reaction in THF so as to obtain a Grignard reagent, then adding paraformaldehyde to the Grignard reagent for performing a Grignard reaction, and after the Grignard reaction is completed, performing separation and recovery of 2-butyne-1-alcohol; and enabling 2-butyne-1-alcohol and phosphorus tribromide to be subjected to a bromination reaction, and after the bromination reaction is completed, performing separation and recovery of the 1-bromine-2-butyne. The Grignard reaction adopted by the production method disclosed by the invention is widely used at present, special production equipment is not needed, reaction conditions are relatively mild, the Grignard reaction is stable in an industrialized production process, and the danger is reduced. The phosphorus tribromide is used for performing bromination on the 2-butyne-1-alcohol, and the utilization rate of the bromine is high; and a generated byproduct namely phosphoric acid is neutralized with pyridine, so that the phosphoric acid is easy to treat.