反应详情

N-Bromosuccinimide (10.0 g) and di-benzoylperoxide (500 mg) were added in five equal portions to a solution of 5-bromo-7-methylbenzofuran (9.7 g) stirring at reflux in CCl4 (100 ml), whilst being irradiated with an 850 W lamp. After the final addition, the reaction was stirred at reflux for a further 2 hours, then cooled to room temperature. The solution was filtered and the filtrate washed with 2N NaOH--H2O (40 ml), brine (40 ml), dried over MgSO4, filtered and the solvent removed under reduced pressure. Purification by MPLC (1% ethyl acetateln-hexane) gave 5-bromo-7-bromomethyl benzofuran as a dlear oil (4.2 g). 1H NMR (360 MHz,CDCl3)δ4.86 (2H, s), 6.69 (1H, d, J=3.0 Hz), 7.54 (1H, s), 7.62 (1H, s), 7.86 (1H, d, J=3.0 Hz).

1. customwhilst being irradiated with an 850 W lamp
2. additionAfter the final addition
3. stirringthe reaction was stirred
4. temperatureat reflux for a further 2 hours
5. filtrationThe solution was filtered
6. washthe filtrate washed with 2N NaOH--H2O (40 ml), brine (40 ml)
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. customthe solvent removed under reduced pressure
10. customPurification by MPLC (1% ethyl acetateln-hexane)