反应详情

温度

0 °C

To a suspension of 5 g (21 mmoles) of ethyl 7-hydroxy-4-oxo-chromen-2-carboxylate and 5 g (45 mmoles) of anhydrous calcium chloride in 100 mL of absolute ethanol, cooled at 0° C., were added 3 g of sodium borohydride in several portions and the mixture was stirred at room temperature for 16 hours. Further 1 g of sodium borohydride was added and stirred for an additional 2 hours. The reaction mixture was suspended in 200 mL of water and acidified slowly with HCl. The precipitate was filtered, washed with water and dried at vaccum to give 2.7 g de 7-hydroxy-2-(hydroxymethyl)-chromen-4-one as a solid, yield 66%, mp 250-252° C.

1. stirringstirred for an additional 2 hours
2. filtrationThe precipitate was filtered
3. washwashed with water
4. customdried at vaccum