N-bromobutanimide → 3-Bromo-6-methoxy-2-(4-methoxyphenyl)-benzo[b]thiophene

Participants

Reaction Conditions

Reaction Steps

To a 500 mL round bottom flask containing 6-methoxy-2-(4-methoxyphenyl)benzo[b]thiophene (22 g, 81 mmol) in THF (250 mL) at 0° C. was added NBS (15 g, 84 mmol). The reaction mixture was stirred at 0° C. for 60 min and then allowed to warm to room temperature and stirred for an additional 2 h. Upon completion the reaction mixture was concentrated to 50% volume and quenched with sat. aq. sodium thiosulfate solution. The resulting solution was extracted with diethyether 3× and the combined organic solvent was dried over anhydrous MgSO4, filtered and concentrated in vacuo to afford 3-bromo-6-methoxy-2-(4-methoxyphenyl)-benzo[b]thiophene (27.5 g, 79 mmol, 97% yield). 1H NMR (400 MHz, CDCl3) δ ppm=7.63 (d, J=9.1 Hz, 1H), 7.55-7.61 (m, 2H), 7.19 (d, J=2.5 Hz, 1H), 6.96-7.02 (m, 1H), 6.87-6.95 (m, 2H), 3.81 (s, 3H), 3.79 (s, 3H).

Provenance & Evidence