2-AMINO-4-CHLOROBENZOIC ACID

67-56-1

89-77-0

5900-58-3

To a single-necked flask was added 10 g of 2-amino-4-chlorobenzoic acid and 150 ml of methanol, and the mixture was cooled to 0-5 °C. 10.4 g of thionyl chloride was slowly added dropwise with stirring. After the dropwise addition, the reaction mixture was heated to reflux for 24 hours. After completion of the reaction, it was cooled to room temperature and methanol was removed by distillation under reduced pressure. To the residue, 100 ml of ethyl acetate and 100 ml of 5% sodium carbonate solution were added, stirred thoroughly and left to stratify. The aqueous layer was separated and the organic layer was washed with 100 ml of water. The organic phase was dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give 8.9 g of methyl 2-amino-4-chlorobenzoate in 82% yield.