5-Bromo-2-fluorobenzaldehyde

446-52-6

93777-26-5

Example 3: In a reactor equipped with an electric stirrer, a thermometer, a dropping funnel and a condenser tube, 500 mL of aqueous sulfuric acid solution was added. Subsequently, a mixture of 167 g (1 mol) of potassium bromate and 124.1 g (1 mol) of 2-fluorobenzaldehyde was slowly added dropwise to the reaction system, the reaction temperature was maintained at 90°C, and the dropwise process continued for 2 to 3 hours. Upon completion of the reaction, 1000 mL of water was added to the system and extracted using methyl tert-butyl ether. The organic phase was subsequently washed with aqueous sodium sulfite and dried over anhydrous sodium sulfate. The dried organic phase was filtered and concentrated to remove the methyl tert-butyl ether to give a brownish red oil. Finally, the 63-65°C/3 mmHg fraction was collected by vacuum distillation to afford 178 g of the target product 5-bromo-2-fluorobenzaldehyde in 88% yield and 97% purity.