894853-42-0

72754-05-3

Tert-butyl 3-(2-amino-5-bromopyridin-3-yl)acrylate (2.5 g, 8.35 mmol) was dissolved in anhydrous methanol (50 mL) and sodium methanolate (8.5 mL, 4.9 M solution, 41.75 mmol) was added. The reaction mixture was heated to reflux for 2 hours and subsequently cooled to room temperature. The mixture was cooled in an ice water bath and water (100 mL) was added with vigorous stirring to precipitate. The solid was collected by filtration and washed with water (20 mL). The filtrate was neutralized with 1 M aqueous hydrochloric acid, precipitated again, filtered and washed with water (20 mL). The solids obtained twice were combined and dried under reduced pressure to give the off-white target product 6-bromo-1,8-naphthyridin-2(1H)-one (1.75 g, 93% yield). The product was confirmed by 1H NMR (300 MHz, DMSO-d6): δ 8.43 (d, 1H, J=2.5Hz), 8.06 (d, 1H, J=2.5Hz), 7.60 (d, 1H, J=9.1Hz), 6.44 (d, 1H, J=9.1Hz); ESIMS m/z 225 (100%), 227 (100%) ) [C8H5N2OBr + H]+.