Iodoethane → 4-Bromo-1-ethoxy-2-fluorobenzene

Participants

Reaction Steps

A mixture of 2-fluoro-4-bromophenol (19.1 g), sodium hydroxide (6 g), ethyl iodide (46.8 g), tetra-n-butylammonium bromide (3.2 g), dichloromethane (250 cm3) and water (250 cm3) was stirred vigorously at the ambient temperature for 51/2 hours, then allowed to stand for a further 68 hours. The organic layer was separated and the aqueous layer was washed with dichloromethane; the combined organic layers were then dried over anhydrous sodium sulphate. The solvent was removed by evaporation under reduced pressure at a bath temperature maintained below 40° C. The residual oil was purified by column chromatography on a silica gel support, eluting firstly with n-hexane and secondly with dichloromethane. The product-containing fractions were combined, washed with an aqueous solution of sodium metabisulphite, dried over anhydrous sodim sulphate and concentrated by evaporation under reduced pressure to give 4-bromo-2-fluorophenetole (15.2 g) as an oil. The product was shown by gas liquid chromatography to be 93% pure, and was used without further purification.

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