| 摘要 |
PROBLEM TO BE SOLVED: To obtain a 2-bromo-5-fluorobenzoic acid derivative useful as an intermediate for pharmaceuticals and agrochemicals in a short process with a simple operation by reacting a fluorobenzoic acid derivative with a specific bromination agent in the presence of sulfuric acid. SOLUTION: The objective derivative of formula II, e.g. 3-bromo-2,4,5- trifluorobenzoic acid can be produced by reacting (A) a fluorobenzoic acid derivative of formula I (X and Y are each a halogen) with (B) an N-bromoimide- type bromination agent, preferably 1,3-dibromo-5,5-dimethylhydantoin in the presence of sulfuric acid, preferably concentrated sulfuric acid. The reaction is preferably carried out by using 0.3-2 mol of the component B based on 1 mol of the component A at a reaction temperature of -40 to +100 deg.C under atmospheric pressure for about 5-48 hr.
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