To a mixture of 6-chloro-2-(4-fluoro-1H-indol-2-yl)pyridin-3-yl trifluoromethanesulfonate (2 g, 5.1 mmol), allyltributylstannane (2 g, 6.1 mmol) and anhydrous LiCl (256 mg, 6.1 mmol) in THF (30 mL), Pd(PPh3)4 (588 mg, 0.51 mmol) was added under N2 protection. The reaction mixture was stirred at 60° C. overnight. After it was concentrated in vacuo, the residue was purified by column chromatography (PE:EA=400:1˜100:1) to give the product of 2-(3-allyl-6-chloropyridin-2-yl)-4-fluoro-1H-indole (1 g, yield: 68%). 1H-NMR (CDCl3, 400 MHz) δ 9.72 (s, 1H), 7.57 (d, J=8.0 Hz, 1H), 7.12˜7.24 (m, 3H), 7.02 (s, 1H), 6.77 (t, J=8.0 Hz, 1H), 6.04˜6.12 (m, 1H), 5.25 (d, J=10.0 Hz, 1H), 5.13 (d, J=17.2 Hz, 1H), 3.74 (d, J=6.0 Hz, 2H). MS (M+H)+: 287/289.
