Chlorination synthesis method of pyridine derivatives

The invention relates to a chlorination synthesis method of pyridine derivatives, which is characterized by using a special chlorination reactor, wherein a chlorine gas distribution device and a turbine-impeller self-priming stirrer are arranged in the chlorination reactor. On the basis of the traditional chlorination reactor, the chlorine gas distribution device is added, and the stirring form of the reactor is improved, thereby being beneficial to sufficient contact between the chlorine gas and material, enhancing the utilization ratio of the chlorine gas, lowering the consumption of the chlorine gas and facilitating the recycling of the exhaust hydrogen chloride. The measurement and calculation indicate that the utilization ratio of the reactive chlorine gas is higher than 98%, thereby greatly lowering the time and cost for synthesis of 2,3-dichloro-5-trichloromethylpyridine and 2-chloro-5-trichloromethylpyridine.