Boron tribromide → 3-Fluoro-5-methoxyphenol

Participants

Reaction Conditions

Reaction Steps

Under nitrogen atmosphere, 1-fluoro-3,5-dimethoxybenzene (25 g, 160 mmol) was diluted in CH2Cl2 (200 mL, 0.8M) and then cooled to −15° C. Next, BBr3 (176 mL, 176 mmol, 1M in CH2Cl2) was slowly added to the reaction mixture. The reaction mixture was stirred at −15° C. for one and a half hours and at room temperature for 10 minutes. The reaction mixture was then cooled to 0° C. and slowly quenched with water (150 mL). The aqueous layer was then extracted with methylene chloride (3×100 mL). The organic extracts were dried over sodium sulfate and concentrated. Silica gel chromatography (1%-30% EtOAc/Hexanes) gave the mono demethylated product (50-1) (15 g, 67%).

Provenance & Evidence