2,5-Dibromobenzoic acid

88-65-3

610-71-9

First, sodium periodate solution was prepared: 4.3 g (19.9 mmol) of sodium periodate was dissolved in a solvent mixture of 30 mL of water and 18 mL of acetic acid. Subsequently, 10 g (49.7 mmol) of o-bromobenzoic acid and 5.1 g (49.7 mmol) of sodium bromide were added to the reaction flask with the above prepared sodium periodate solution. The reaction mixture was heated to 30°C, at which temperature 4.4 mL of concentrated sulfuric acid was slowly added dropwise. After the dropwise addition was completed, the reaction temperature was raised to 50 °C and the reaction was kept at this temperature for 2-3 hours. The progress of the reaction was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the mixture was cooled to room temperature and poured into ice water to precipitate the solid product. The solid was collected by filtration and the filter cake was washed several times with cold water to give 11.9 g of 2,5-dibromobenzoic acid in 85.6% yield.