Acetic Acid → 1-(3-Fluoro-2,4-dihydroxy-phenyl)-ethanone

Participants

Reaction Conditions

Reaction Steps

A solution of 2-fluoro-3-methoxy-phenol (0.5 g, 3.53 mmol) and dichloromethane is stirred at −78° C. A 1M solution of boron tribromide in dichloromethane (3.9 mL, 3.9 mmol) is added slowly and the mixture is stirred 10 min cold, then warmed to 0° C. and stirred 1 hr. The reaction is quenched with ice and stirred at room temperature overnight. The product is extracted with ethyl acetate (2×50 mL), dried over magnesium sulfate, filtered, and concentrated. The resulting residue is combined with boron trifluoride diethyl etherate (1.3 mL, 10.3 mmol) and acetic acid (0.2 mL, 3.28 mmol) and heated to reflux 8 hr. The mixture is cooled to room temperature, diluted with water (50 mL), and extracted with ethyl acetate (3×50 mL). The combined extracts are dried over magnesium sulfate, filtered and concentrated to about 10 mL volume. The resulting mixture is diluted with hexanes (50 mL), cooled to 0° C., and filtered to give the title compound (310 mg, 58%) as a tan solid. MS ES 171 m+1.

Provenance & Evidence