Methyl 3-bromophenylacetate (4.58 g, 20 mmol, 1.0 eq.) was added to a dry 100 mL three-neck flask under nitrogen protection. Anhydrous tetrahydrofuran (30 mL) was added, followed by the slow dropwise addition of 2.0 M lithium diisopropylammonium THF/heptane/ethylbenzene solution (10.5 mL, 21 mmol, 1.05 eq.) at -78 °C. After dropwise addition, the reaction mixture was stirred at -78 °C for 30 min. Then, iodomethane (2.84 g, 20 mmol, 1.0 eq.) was added and the reaction mixture was gradually warmed to room temperature and stirring was continued for 3 hours. Upon completion of the reaction, 60 mL of water was added to the reaction flask and the organic phase was separated by extraction with 50 mL of dichloromethane. The aqueous phase was extracted twice more with 30 mL of dichloromethane. All organic phases were combined, washed twice with saturated brine solution and dried over anhydrous sodium sulfate. After concentration under reduced pressure, the residue was purified by column chromatography to afford methyl 2-(3-bromophenyl)propionate 3.95 g in 82.3% yield.
