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To a solution of 5-bromo-4-methylpyridine-2-carboxylic acid (650 mg, 3.0 mmol) in methanol (2 mL) was added concentrated sulfuric acid (catalytic amount). The reaction mixture was heated to reflux for 14 hours. After completion of the reaction, the mixture was cooled to 0 °C and neutralized with saturated sodium bicarbonate solution to pH 7-8. The insoluble material was removed by filtration and the filtrate was concentrated under reduced pressure to remove the solvent. The crude product was purified by silica gel column chromatography using a suitable eluent (e.g. petroleum ether/ethyl acetate gradient elution) to afford methyl 5-bromo-4-methylpyridine-2-carboxylate (340 mg, 49% yield) as a white solid.

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