| 摘要 |
A process for the preparation of halogenated benzoic acids of formula (1): <IMAGE> (1) in which R1, R2, R3, R4 and R5 are hydrogen, fluorine, chlorine or bromine atoms or C1-C6-alkyl, C1-C6-alkoxy, nitro, cyano, trifluoromethyl, aidehyde, C1-C4-alkoxycarbonyl, -SO2-C1-C4-alkyl, -SO2-phenyl, -CONH2, -CON(C1-C4-alkyl)2, hydroxy, carboxy, -NH2 or -N(C1-C4- alkyl)2 groups, at least one of the substituents R1-R5 being one of said halogen atoms, which comprises reacting 1 mol of a benzophenone, asymmetrically substituted on the benzene rings A and B, of general formula (2): <IMAGE> (2) in which R1-R10 are as defined above for R1-R5, with about 1 to about 10 mol of an oxidizing agent selected from the group comprising hydrogen peroxide, urea/hydrogen peroxide addition product, an alkali metal peroxide, ammonium, alkali metal or alkaline earth metal peroxodisulfates, pertungstates, perborates or percarbonates, ozone, alkyl- or aryl-percarboxylic acids, alkyl- or aryl-persulfonic acids or persulfuric acid, at temperatures from about -20 DEG to about +100 DEG C.
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