Potassium Carbonate → Methyl 5-phenylthiophene-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

Prepare a mixture of 5-bromo-thiophene-3-carboxylic acid methyl ester (1.86 g, 8.41 mmol), phenylboronic acid (2.05 g, 16.83 mmol), and 1 M aqueous potassium carbonate (12.5 mL, 25.23 mmol) in 1,2-dimethoxyethane (70 mL) and purge with nitrogen for 20 minutes. Add Pd(PPh3)4 (485 mg, 0.42 mmol) and again purge the mixture with nitrogen for 10 minutes. Heat to 80° C. for 24 hours. Evaporate the solvent and redissolve the residue in ethyl acetate. Extract the aqueous phase with ethyl acetate (2×20 mL), wash the combined organic phases brine (40 mL), dry (magnesium sulfate), filter and concentrate. Perform flash chromatography on silica-gel eluting with 10:1 hexane/ethyl acetate to afford 947 mg of 5-phenylthiophene-3-carboxylic acid methyl ester as a white solid. MS: m/e=219 [MH+].

Provenance & Evidence