反应详情

Bromine (0.797 ml, 15.47 mmol) was added to a suspension of zinc dust (8.09 g, 124 mmol in diethyl ether (150 ml) at RT. After 5 minutes, ethyl 2-bromoacetate (6.86 ml, 61.9 mmol) was added drop wise over a time period of 20 minutes and the reaction mixture was heated to reflux for 2 hours. 7-bromo-4-fluoro-2-methoxy-9H-xanthen-9-one (10 g, 30.9 mmol) was added in one portion, followed by THF (100 ml) and the reaction mixture was heated to reflux for 3 hours. The reaction mixture was quenched with aqueous saturated NH4Cl solution (100 mL) and EtOAc (100 mL) and stirred 2 hours at RT. The solution was filtered and the organic phase was separated. The solvent was removed under educed pressure to afford ethyl 2-(7-bromo-4-fluoro-9-hydroxy-2-methoxy-9H-xanthen-9-yl)acetate (12.7 g, 30.9 mmol, 100% yield).

1. temperaturethe reaction mixture was heated
2. temperatureto reflux for 2 hours
3. temperaturethe reaction mixture was heated
4. temperatureto reflux for 3 hours
5. customThe reaction mixture was quenched with aqueous saturated NH4Cl solution (100 mL) and EtOAc (100 mL)
6. filtrationThe solution was filtered
7. customthe organic phase was separated
8. customThe solvent was removed