5337-09-7

2-Bromo-3-nitrobenzoic Acid Methyl Ester is an halogenated benzoic acid and an intermediate in the synthesis of anti-inflammatory drug Balsalazide (B116300).

General procedure for the synthesis of methyl 2-bromo-3-nitrobenzoate from methanol and 2-bromo-3-nitrobenzoic acid: Example 4: 100 g (406 mmol) of 2-bromo-3-nitrobenzoic acid and 22 g (609 mmol) of concentrated hydrochloric acid were added to a reactor followed by 1 liter of methanol. The reaction mixture was heated under reflux conditions for 24 hours. After completion of the reaction, it was cooled to room temperature and the precipitated solid product was collected by filtration. The solid was washed sequentially with deionized water and ethanol and then dried. Finally, the dried product was purified by recrystallization with ethanol. Methyl 2-bromo-3-nitrobenzoate 94.6 g (363 mmol) was obtained in 89.5% yield of the theoretical value.

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