反应详情

Alternative method: 100.0 g (423 mmol) of 5,7-dihydroxy-3-(2-hydroxyethyl)-4-methyl-2H-1-benzopyran-2-one (Example 49), 175.5 g (1270 mmol) of potassium carbonate and 150.2 g (1058 mmol) of methyl iodide are stirred under reflux for 4 hours in 1800 ml of ethanol. The solution is filtered, evaporated, extracted with chloroform, and the organic phase is washed with water, dried with Na2SO4 and re-evaporated. Yield 49.3 g (44%); m.p. 148°-150° C. (from isopropanol/TBME).

1. filtrationThe solution is filtered
2. customevaporated
3. extractionextracted with chloroform
4. washthe organic phase is washed with water
5. dry with materialdried with Na2SO4
6. customre-evaporated