Add 250 g of 2-chloro-6-fluorotoluene and 0.5 ml of phosphorus trichloride (the addition of phosphorus trichloride in this step can improve the quality of the product) to a 500 ml four-necked glass reaction flask equipped with a reflux condenser tube, an off-gas absorption device and a thermometer, and pass the chlorine gas under the irradiation of a metal halide lamp and keep it under the 180 Chlorine gas was passed under the condition of to obtain 2-chloro-6-fluorobenzyl chloride. Detect the content of 2-chloro-6-fluorobenzyl chloride in the liquid phase of the reaction bottle by gas chromatography, and when the content of 2-chloro-6-fluorobenzyl chloride is detected to be less than 0.5%, stop passing the chlorine gas, and simultaneously When the content of 2-chloro-6-fluorobenzyl chloride is detected to be less than 0.5%, stop passing chlorine gas, and at the same time, pass nitrogen into the reaction bottle to remove the unreacted chlorine in the bottle.
