Water → 4-Bromo-2-fluorophenol

Participants

Reaction Steps

To a stirred solution of 2-fluorophenol (22.4 g, 0.2 mole) in methylene chloride (250 ml) which was cooled to ~3° C. in an ice bath, was added, all at once, bromine (31.97 g, 0.2 mole). The resulting solution was stirred at ice bath temperature for two hours and then at room temperature for 1 hour. The mixture was poured into water (600 ml) containing excess sodium bisulfite. The organic phase was separated and the aqueous phase was washed with additional methylene chloride (200 ml). The combined organic extracts were washed with saturated sodium bicarbonate, dried (MgSO4) and the solvent evaporated to give the desired 2-fluoro-4-bromophenol as a colorless oil (34.5 g, 90%). The NMR (CDCl3) was consistent with the assigned structure. The gc of this material showed that it contained only a trace of the 2,6-isomer. This material was used directly in the following step without additional purification.

Provenance & Evidence