220514-28-3

The general procedure for the synthesis of methyl 5-bromo-2-methyl-3-nitrobenzoate from methanol and 2-methyl-3-nitro-5-bromobenzoic acid was as follows: 2-methyl-3-nitro-5-bromobenzoic acid (21.2 g, 81.5 mmol) was dissolved in SOCl2 (100 mL), and the mixture was heated to reflux until it clarified (ca. 1.5 h). After the reaction was complete, the mixture was cooled and concentrated in vacuum. The residue was added to 250 mL of methanol in batches and the resulting mixture was stirred overnight under reflux conditions. Upon completion of the reaction, the mixture was cooled and concentrated. The residue was dissolved in 300 mL of ethyl acetate, washed sequentially with saturated aqueous NaHCO3 and brine, dried over MgSO4 and concentrated. The residue was purified by silica gel column chromatography (eluent: petroleum ether:ethyl acetate=20:1, v:v) to afford methyl 5-bromo-2-methyl-3-nitrobenzoate (21.2 g, yield: 95%) as a light yellow solid.

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