General procedure for the synthesis of 4-bromo-2-ethyl-1-methoxybenzene from 1-ethyl-2-methoxybenzene:
1. 2-Ethylanisole (3.2 g, 23.5 mmol) was dissolved in acetonitrile (100 mL) under stirring conditions.
2. N-bromosuccinimide (4.59 g, 25.8 mmol) was added to the above solution to initiate the reaction.
3. The reaction mixture was stirred continuously at room temperature for 18 hours.
4. After completion of the reaction, the reaction solution was concentrated under reduced pressure. 5.
5. Ether (100 mL) was added to the concentrated crude product and the ether layer was washed with deionized water (2 x 100 mL).
6. Separate the organic layer and concentrate under reduced pressure.
7. The product was purified by fast column chromatography using hexane-ethyl acetate (70:30 v/v, Rf 0.9) as eluent to afford the target compound 4-bromo-2-ethyl-1-methoxybenzene (4.95 g, 98% yield) as a colorless oil.
Product characterization data: 1H NMR (270 MHz, CDCl3) δ 1.16 (t, J = 7.5 Hz, 3H), 2.59 (q, J = 7.5 Hz, 2H), 3.79 (s, 3H), 6.69 (d, J = 9.4 Hz, 1H), 7.23-7.26 (m, 2H).
