反应详情

温度

0 °C

A dry 100 L glass jacketed reactor equipped with an addition funnel, reflux condenser and temperature probe was charged with 5-bromo-2-(2-fluoro-4-methoxyphenoxy)benzoic acid (2340 g, 6.9 mol). TFA (11.7 L) was carefully added followed by TFAA (1144 mL). Boron trifluoride diethyl etherate (85 mL, 0.68 mol) was then carefully added. Stirring was continued to 4 hours at which point the reaction was transferred to another 100 L glass reactor containing 35.1 L of water cooled to 0° C. The resulting slurry was allowed to warm to RT and stir for 1 hour. The solids were filtered and washed with water (4.7 L) and 3 N NaOH (2×3.5 L) and water (7 L). The solids were transferred into a 22 L reactor and acetone (4.7 L) was added. The solids were slurried for 1.5 hour and the filtered, washing well with acetone (4.7 L). An additional slurry with acetone (6.4 L @ 45° C.) provided 1310 g of 7-bromo-4-fluoro-2-methoxy-9H-xanthen-9-one as an off white solid.

1. customequipped with an addition funnel
2. temperaturereflux condenser
3. customwas transferred to another 100 L glass reactor
4. temperatureto warm to RT
5. stirringstir for 1 hour
6. filtrationThe solids were filtered
7. washwashed with water (4.7 L) and 3 N NaOH (2×3.5 L) and water (7 L)
8. customThe solids were transferred into a 22 L reactor
9. additionacetone (4.7 L) was added
10. waitThe solids were slurried for 1.5 hour
11. washthe filtered, washing well with acetone (4.7 L)