Toluene → 3-Bromo-4-(4-methoxyphenyl)thiophene

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3,4-dibromothiophene (Scheme I, 1) (5 g, 20.7 mmol), 4-methoxyphenylboronic acid (Scheme I, 2, X1=4-methoxyphenyl) (3.14 g, 20.7 mmol), sodium carbonate (4.38 g, 41.3 mmol), toluene (100 mL), in a mixture of ethanol (60 mL) and water (40 mL) was added Pd(PPh3)4 (2.02 g, 1.75 mmol) under nitrogen. The mixture was stirred at 75° C. for 13 h, poured into water (60 mL), and extracted with ethyl acetate (60 mL×3). The organic extracts were dried over anhydrous magnesium sulfate (10 g), evaporated, and purified by column chromatography on silica gel (petroleum ether/ethyl acetate=150:1) to give 3-bromo-4-(4-methoxyphenyl)thiophene (Scheme I, 2, X1=4-methoxyphenyl) (1.7 g, yield 30.6%). 1H NMR (DMSO-d6 400 MHz): δ 7.84 (d, J=3.2 Hz, 1H), 7.64 (d, J=3.2 Hz, 1H), 7.42 (d, J=8.8 Hz, 2H), 6.97 (d, J=8.8 Hz, 2H), 3.78 (s, 3H).

Provenance & Evidence