General procedure for the synthesis of 3-ethoxybromobenzene: Sodium hydride (18.4 g, 60% oil dispersion, 460 mmol) was suspended in 1000 mL of DMF and the mixture was cooled to 0 °C. 3-Bromophenol (72 g, 419 mmol) was placed in a dropping funnel and heated using a hot air gun to melt it and then added dropwise to the cooled sodium hydride suspension. After the dropwise addition, the reaction mixture was continued to be stirred at 0 °C for 30 min. Subsequently, iodoethane (40 mL, 78 g, 503 mmol) was slowly added dropwise and the mixture was stirred for 12 hours, during which time it was allowed to warm naturally to room temperature. Upon completion of the reaction, water (1000 mL) was carefully added to quench the reaction, followed by extraction with ethyl acetate (4 x 500 mL). The organic layers were combined, washed with water (8 x 200 mL), dried over anhydrous sodium sulfate, filtered and concentrated. The residue was distilled under reduced pressure and the fractions with boiling points above 120 °C were collected to give 70 g of the target product 3-ethoxybromobenzene in 84% yield. The density of the product was 1.47 g/mL.
