The general procedure for the synthesis of methyl 4-bromo-2-methoxybenzoate from 2-hydroxy-4-bromobenzoic acid and iodomethane was as follows: 4-bromo-2-hydroxybenzoic acid (1.00 g, 4.61 mmol) was dissolved in acetone (25 mL), followed by the addition of iodomethane (1.15 mL, 18.4 mmol) and potassium carbonate (2.55 g, 18.4 mmol). The reaction mixture was heated to reflux and the reaction was continued overnight. After completion of the reaction, it was cooled to room temperature, filtered to remove insoluble material, and the filtrate was concentrated under reduced pressure to obtain the crude product. The crude product was purified by fast column chromatography (Biotage column, eluent: 10% ethyl acetate/hexane) to give 0.955 g (85% yield) of the target compound, methyl 4-bromo-2-methoxybenzoate, as a yellow oil. The product was analyzed by LC/MS showing a m/z of 245.0 (MH+) and a retention time of 3.13 min. 1H NMR (400 MHz, CD2Cl2) data were as follows: δ 3.84 (s, 3H), 3.90 (s, 3H), 7.12-7.20 (m, 2H), 7.62 (d, 1H).
