| abstract |
The present invention provides a method for the preparing of 2-chloro-5-trifluoromethylpyridine, comprising: 3-trifluoromethylpyridine reacting with chlorine gas in gas phase at a reaction temperature of 150°C-350°C and in the presence of a catalyst, to obtain 2-chloro-5-trifluoromethylpyridine. The catalyst is chosen from at least one of ZSM-5, 5A, β and 13X molecular sieves, Si/Al of the ZSM-5 molecular sieve is 50-300, and balance cation of the ZSM-5 molecular sieve is chosen from at least one of H<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>, and Ca<sup>2+</sup>. |