反应详情

温度

27 °C

3.0 g of 3-hydroxy-7-methoxy-phthalide [see B. L. Chenard et al., J. Org. Chem. 49, 318 (1984)] are introduced in portions into a suspension of 8.2 g of aluminium trichloride in 50 ml of methylene chloride, the internal temperature being maintained at 27° C. The mixture is stirred at room temperature for a further 5 hours, is then poured into 200 ml of ice-cold 1N hydrochloric acid and extracted three times with 200 ml of ethyl acetate each time. The organic solution is washed with sodium chloride solution and dried over anhydrous magnesium sulfate. Evaporation of the solvent and recrystallisation from ethyl acetate and n-hexane yield pure 3,7-dihydroxyphthalide, m.p. 124°-126° C.

1. extractionextracted three times with 200 ml of ethyl acetate each time
2. washThe organic solution is washed with sodium chloride solution
3. dry with materialdried over anhydrous magnesium sulfate
4. customEvaporation of the solvent and recrystallisation from ethyl acetate and n-hexane