Methyl iodide → 3,5-Dibromoanisole

Participants

Reaction Steps

To a suspension of 3,5-dibromophenol (20 g, 79.39 mmol) and potassium carbonate (21.95 g, 158.78 mmol) in acetone (100 mL) was added iodomethane (24.79 g, 174.65 mmol) at room temperature. The resulting light yellow color mixture was heated to reflux and stirred for 15 h at which time TLC analysis of the mixture indicated the absence of starting material. Then, the reaction mixture was cooled to room temperature and diluted with water (200 mL) and ethyl acetate (200 mL). The two layers were separated and the aqueous layer was extracted with ethyl acetate (100 mL). The combined extracts were washed with brine solution (250 mL) and dried over anhydrous magnesium sulfate. Filtration of the drying agent and the concentration of the solution under reduced pressure gave the crude residue which was purified by using an ISCO 330 g column chromatography, eluting with 0-3% ethyl acetate in hexanes to obtain 1,3-dibromo-5-methoxy-benzene (20.47 g, 97%) as a white solid: EI(+)-HRMS m/e calcd for C7H6Br2O (M)+ 263.8780, found 263.8785.

Provenance & Evidence