反应详情

5-Bromo-6-hydroxy-nicotinic acid (Preparation 238, 4 g, 18.4 mmol), HATU (13.95 g, 36.71 mmol), O,N-Dimethyl-hydroxylamine hydrochloride (2.15 g, 22.02 mmol) and DIPEA (15.82 mL, 91.75 mmol) were taken in anhydrous DMF (30 mL). The mixture was stirred at room temperature for 16 hours. The reaction mixture was diluted with EtOAc (150 mL), washed with saturated aq. Na2CO3 (2×50 mL), water (4×30 mL), brine (30 mL), dried (Na2SO4) and evaporated in vacuo. The crude mixture was purified by column chromatography on silica gel (gradient of EtOAc:Hex 4:6 to 6:4) to afford the title compound as light yellow sticky solid in 38%, 1.8 g.

1. washwashed with saturated aq. Na2CO3 (2×50 mL), water (4×30 mL), brine (30 mL)
2. dry with materialdried (Na2SO4)
3. customevaporated in vacuo
4. customThe crude mixture was purified by column chromatography on silica gel (gradient of EtOAc:Hex 4:6 to 6:4)