A mixture of ethyl 6-bromo-1H-indole-2-carboxylate (2.5 g) and 4-methylphenylboric acid (1.39 g), potassium carbonate (2.58 g) and toluene/ethanol/water (90/9/9 ml) was stirred at room temperature for one hour. Into the reaction mixture was added tetrakis(triphenylphosphine)palladium (0.32 g), and the resulting mixture was heated at reflux for 18 hours. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic layer was washed with an aqueous saturated solution of sodium chloride and was dried with magnesium sulfate. After concentration under reduced pressure, the residue was subjected to purification using column chromatography (ethyl acetate/hexane 1:5→1:2→1:1) and to recrystallization (ethyl acetate/hexane) to obtain ethyl 6-(4-methylphenyl)-1H-indole-2-carboxylate (1.92 g) as colorless crystals.
