3177-80-8

88377-29-1

General procedure for the synthesis of 2-bromo-3-methoxybenzoic acid from 2-amino-3-methoxybenzoic acid: 2-amino-3-methoxybenzoic acid (4.00 g, 23.9 mmol) was dissolved in 10% aqueous hydrobromic acid (54 ml) at 0 °C. Subsequently, an aqueous solution of sodium nitrite (1.65 g, 23.9 mmol) (17 ml) was slowly added. A 48% hydrobromic acid solution (22 ml) of copper (I) bromide (3.78 g, 26.3 mmol) was added dropwise to the reaction system under stirring. The reaction mixture was gradually warmed up to 60°C and maintained at this temperature for 2 hours. After completion of the reaction, the mixture was cooled to 0°C and the resulting precipitate was collected by filtration. The precipitate was washed with cold water and purified by recrystallization in water to finally obtain pure 2-bromo-3-methoxybenzoic acid (4.07 g, 74% yield). The product was analyzed by mass spectrometry (EI) and the molecular ion peak (MH+) of C8H7BrO3 was 232.