反应详情

温度

2.5 °C

Boron tribromide (12.89 g, 0.051 mol) was dissolved in dichloromethane (50 ml) and cooled to 0-5° C. A solution of methyl 2-(3-methoxyphenoxy)phenylacetate (7.0 g; 0.026 mol) in dichloromethane (80 ml) was added dropwise, with stirring over 1 hour. After stirring at 0°-5° C. for 20 minutes the mixture was added dropwise, with stirring to absolute methanol (100 ml) maintaining the temperature at 0°-5° C. The resulting solution was poured into water (250 ml) containing sodium bicarbonate (12 g), and the resulting mixture was extracted with ether (500 mls). The organic phase was washed with water (3×200 ml) and saturated brine (150 ml). After drying and filtration, evaporation of the ether solution gave methyl 2-(3-hydroxyphenoxy)phenylacetate (D) (6.12 g, 92.3% yield) as a brown gum. This material was suitable for use in subsequent steps without further purification. However, chromatography using mixtures of ether and hexane as eluant gave material of higher purity as a viscous golden oil which rapidly darkened on exposure to air.

1. stirringAfter stirring at 0°-5° C. for 20 minutes the mixture
2. additionwas added dropwise
3. temperaturemaintaining the temperature at 0°-5° C
4. extractionthe resulting mixture was extracted with ether (500 mls)
5. washThe organic phase was washed with water (3×200 ml) and saturated brine (150 ml)
6. customAfter drying
7. filtrationfiltration, evaporation of the ether solution