反应详情

温度

85 °C

To a stirred solution of 2-(hydroxymethyl)-5-[(4-methoxybenzyl)oxy]-4H-pyran-4-one (Intermediate 289, 101.7 g, 0.388 mol) in pyridine (1.35 L) was added hydroxylamine hydrochloride (134.7 g, 1.94 mol). The reaction mixture was heated at 85° C. for 4 hours, then evaporated to dryness and triturated with water (700 mL). The precipitate was collected by filtration and washed with water (250 mL). The solids were then stirred in isopropanol (100 mL) for 12 hours, collected by filtration and dried under vacuum to afford the title compound as a white solid (41.2 g, 38%).

1. customevaporated to dryness
2. customtriturated with water (700 mL)
3. filtrationThe precipitate was collected by filtration
4. washwashed with water (250 mL)
5. filtrationcollected by filtration
6. customdried under vacuum