反应详情

Cesium carbonate (5.46 g, 16.6 mmol) was added to a solution of 8-hydroxy-2,2-dimethyl-4H-1,3-benzodioxin-4-one (123a, 1.50 g, 7.73 mmol) in N,N-dimethylformamide (31 mL) and the mixture stirred at room temperature for five minutes before 2-iodopropane (1.00 mL, 10.0 mmol) was added. The mixture was stirred at room temperature for 80 minutes, then partitioned between deionized water (30 mL) and ethyl acetate (2×75 mL). The combined organic extracts were dried over magnesium sulfate, filtered, concentrated under vacuum, and purified by column chromatography (ethyl acetate/heptane) to give 2,2-dimethyl-8-(propan-2-yloxy)-4H-1,3-benzodioxin-4-one (123b, 1.41 g, 77% yield) as a colorless gel which slowly crystallized to a white solid.

1. additionwas added
2. custompartitioned between deionized water (30 mL) and ethyl acetate (2×75 mL)
3. dry with materialThe combined organic extracts were dried over magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated under vacuum
6. custompurified by column chromatography (ethyl acetate/heptane)