反应详情

温度

90 °C

A 500 mL round bottom flask was charged with 2-fluoro-3-methoxybenzaldehyde 77.A (available from Aldrich) (28.6 g, 186 mmol), 2,2-dimethyl-1,3-dioxane-4,6-dione (available from Aldrich) (34.8 g, 241 mmol), and water (350 mL). The heterogeneous mixture was stirred for 2 hours at 90° C. (reflux), cooled to room temperature, and filtered. The resulting off-white solid was triturated with ether to afford 5-(2-fluoro-3-methoxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione 77.B (30.6 g, 58.8% yield) as a crystalline white powder.

1. temperature(reflux)
2. temperaturecooled to room temperature
3. filtrationfiltered
4. customThe resulting off-white solid was triturated with ether