PROCESS FOR PREPARING 3-CHLORO-4-FLUORONITROBENZENE.

摘要

This improved process for preparing 3-chloro-4-fluorintro-benzene comprises chlorinating 4-fluoro nitrobenzene in the presence of a catalyst. The catalyst is specified to be (1) iodine or an iodine cpd. and iron or an iron cpd. or (2) iodine or an iodine cpd. and antimony or an antimony cpd. The iron cpd. is pref. FeCl2 or FeCl3. Its weight ratio to the 4-fluoro nitrobenzene is 0.1-10 wt.%. The antimony cpd. is pref. SbCl3 or Sb Cl5. The iodine or iodine cpd. is pref. iodine, iodine chloride, hydrogen iodide, iron iodides etc. Its wt. ratio to the 4-fluoro nitrobenzene is 0.3-3.0 wt.% (pref. 0.01-1.0 wt.%). The reaction temp. pref. lies between 20 and 120 deg. C and the reaction time is normally 0.5-50 hours. The chlorinating agent is pref. chlorine gas.