| abstract |
The invention discloses a preparation method of 2-chloro-3-trifluoromethylpyridine, comprising the following operation steps: (1) adding 2, 3, 6-trichloro-5- Trifluoromethylpyridine, acid binding agent, catalyst, turn on the circulating water pump to replace hydrogen in vacuum, the catalyst is added in an amount of 0.01 to 0.5% of the reaction system; (2) the temperature of the reductive dechlorination reaction is controlled to be ‑10 ℃ to 65 ℃, the reaction hydrogen pressure is 0.1MPa～2.0MPa, and the reaction time is 4～24 hours; (3) the obtained reaction solution is filtered, rectified and purified successively to complete the separation of the corresponding product and the unreacted raw materials. The preparation method of 2-chloro-3-trifluoromethylpyridine provided by the invention has the advantages of simple process, easy operation, favorable for industrial production, and the obtained product has high purity, the purity is more than 98%, and a plurality of useful products are produced at one time , in terms of useful product selectivity, the selectivity is 95%, the single raw material conversion rate is above 95%, and the production cost is low. |