反应详情

温度

80 °C

To a suspension of sodium hydride (16.4 g) in absolute dioxane (700 ml) stirred at 80° C., was slowly added a mixture of o-hydroxyacetophenone (31.0 g) and N-benzyl-N-methylglycine ethyl ester (40 g) in dioxane (100 ml), and the resulting solution was boiled for 19 hours before being evaporated in vacuo. The residue was dissolved in ethanol and the mixture was saturated with dry HCl and stirred at room temperature for 18 hours. After evaporation the residue was taken up in chloroform and washed with water. Evaporation of the dried organic extracts yielded an oil (40 g) which was chromatographed on alumina eluting with chloroform to give the title chromone as a yellow oil (17.8 g).

1. additionwas slowly added
2. custombefore being evaporated in vacuo
3. dissolutionThe residue was dissolved in ethanol
4. stirringstirred at room temperature for 18 hours
5. customAfter evaporation the residue
6. washwashed with water
7. customEvaporation of the dried organic extracts