Methyl iodide → 3,5-Dibromoanisole

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.

1. temperatureThe resulting light yellow color mixture was heated
2. temperatureto reflux
3. customThe two layers were separated
4. extractionthe aqueous layer was extracted with ethyl acetate (100 mL)
5. washThe combined extracts were washed with brine solution (250 mL)
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationFiltration of the drying agent
8. customthe concentration of the solution under reduced pressure gave the crude residue which
9. customwas purified
10. washeluting with 0-3% ethyl acetate in hexanes

ORD record

ord-78c258160ab04b2a90fb37cf65f55d73

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08093253B2