To a solution of methyl 2-bromo-1-(1-phenylethyl)-1H-indole-3-carboxylate (0.30 g, 0.84 mmol) and tetrakis(triphenylphosphine) palladium(0) (0.09 g, 0.08 mmol) in tetrahydrofuran (20 mL) was added cyclopropylzinc(II) bromide (6.0 mL, 0.5 mol/L in tetrahydrofuran). The reaction mixture was stirred at reflux for 12 hours. After the reaction, it was cooled to room temperature and diluted with water (100 mL). The product was extracted with ethyl acetate (100 mL), dried over anhydrous sodium sulfate, concentrated and purified by column chromatography (silica gel: ethyl acetate:petroleum ether=1:10) to give the crude product methyl 2-cyclopropyl-1-(1-phenylethyl)-1H-indole-3-carboxylate (0.22 g, 82%) as a yellow oil.
