| 摘要 |
HOE 92/F 050 Process for the selective dehalogenation of orthohalogenonitrobenzenes The present invention relates to a novel process for the selective dehalogenation of ortho-halogenonitrobenzenes, halogen being chlorine, bromine or a combination thereof, wherein, in nitrobenzenes of general formula (I): (I) wherein X1 and X3 or X1 and X5 are in each case chlorine, bromine or a combination thereof and the remaining substituents X independently of one another are hydrogen, fluorine or C1-C4-alkyl, the halogen atoms X1 and X5 are each replaced with hydrogen atoms by reaction with copper in the presence of a proton donor. Access to the industrially relevant 4-chloro-3-fluoro-nitrobenzene from 2,4-dichloro-3-fluoronitrobenzene or 2,4-dichloro-5-fluoronitrobenzene is of particular interest.
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