Methyl 3-iodo-4-[(trifluoroacetyl)amino]benzoate (0.60 g, 1.61 mmol) and 3-phenyl-1-propyne (0.20 mL, 1.61 mmol) were used as raw materials and mixed with 1,1,3,3-tetramethylguanidine (2.02 mL, 16.08 mmol), bis(triphenylphosphine)palladium(II) chloride (0.113 g, 0.16 mmol) and cuprous iodide (I) (0.031 g, 0.16 mmol) were mixed in N,N-dimethylformamide (15 mL). The reaction mixture was stirred at 50 °C overnight under argon protection. Upon completion of the reaction, the reaction mixture was concentrated and purified by column chromatography using heptane/ethyl acetate (4:1) as eluent to afford 0.18 g of methyl 1-benzyl-1H-indole-5-carboxylate in 82% yield. The product was confirmed by 1H NMR (DMSO-d6) and mass spectrometry (ESI): 1H NMR δ 11.43 (br s, 1H), 8.14 (d, 1H), 7.66 (dd, 1H), 7.29-7.38 (m, 5H), 7.21-7.26 (m, 1H), 6.31 (s, 1H), 4.09 (s, 2H), 3.82 ( s, 3H); MS (ESI) m/z 264 [M-1].
