511541-63-2

511541-62-1

77-78-1

511541-63-2

General procedure for the synthesis of 3-bromo-6-methoxypyridin-2-amine from 6-amino-5-bromopyridin-2-ol and dimethyl sulfate: 11.58 g (61 mmol) of 6-amino-5-bromopyridin-2-ol was suspended in 200 mL of acetone and 10.3 g (184 mmol) of potassium hydroxide pellets and 10 g (80 mmol) of dimethyl sulfate were added sequentially. The reaction mixture was stirred at room temperature for 4 hours and then concentrated to dryness under reduced pressure. To the residue was added 400 mL of water followed by four extractions with 300 mL of ethyl acetate. The organic phases were combined, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by rapid column chromatography on silica gel, the eluent being a solvent mixture of hexane/ethyl acetate 1:1, v/v, to give 3.455 g (28% yield) of 3-bromo-6-methoxypyridin-2-amine as an orange oil.1H-NMR (400 MHz, DMSO-d6) δ: 7.54 (d, J = 2 Hz, 1H, H-4), 6.10 (s, br , 2H, NH2), 5.90 (d, J = 2 Hz, 1H, H-3), 3.75 (s, 3H, OCH3). Mass spectrum (MS) m/e (relative abundance): 204 (M+H+, 100).