1052714-46-1

General procedure for the synthesis of 6-bromo-5-fluoro-2-pyridinecarboxylic acid from 2-bromo-3-fluoro-6-methylpyridine: Potassium permanganate (1.0 eq.) was added to a solution of 2-bromo-3-fluoro-6-methylpyridine (1.0 eq.) in water (30 mL). The reaction mixture was heated at 100 °C for 5 hours and then potassium permanganate (1.0 eq.) was added. After continuing to heat the reaction for 48 hours, the reaction mixture was filtered through a diatomaceous earth pad (4 cm × 2 in.) and washed with deionized water (150 mL). The combined aqueous phases were acidified with 1 N hydrochloric acid to pH = 4 and subsequently extracted with ethyl acetate (200 mL). The organic phase was washed with saturated sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated to give 6-bromo-5-fluoro-2-pyridinecarboxylic acid in 17% yield as a white solid.LCMS (m/z): 221.9 (MH+); retention time (Rt) = 2.05 min.

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