To a mixture of tert-butyl 5-bromo-3-iodo-1H-indole-1-carboxylate (1.750 g, 4.146 mmol, synchem), 3-quinolineboronic acid (1.076 g, 6.22 mmol), Pd(PPh3)4 (0.240 g, 0.207 mmol) and potassium carbonate ((1.719 g, 12.439 mmol) in dioxane (3.0 mL) was added H2O (1.0 mL) and the reaction was heated at 60° C. for 42 h. Saturated NaHCO3 solution (5.0 mL) was added to the mixture. The resulting mixture was extracted with EtOAc. The organic phases were combined, dried with sodium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography to give tert-butyl 5-bromo-3-(quinolin-3-yl)-1H-indole-1-carboxylate (642 mg, 36.6%) as a white foam. MS (ESI, pos. ion) m/z: 423 (M+1); 1H NMR (400 MHz, DMSO-d6) δ ppm 1.68 (s, 9H), 7.62 (dd, J=8.8, 1.8 Hz, 1H), 7.67 (t, J=7.8 Hz, 1H), 7.79 (t, J=7.3 Hz, 1H), 8.07 (d, J=8.5 Hz, 1H), 8.13-8.20 (m, 3H), 8.30 (s, 1H), 8.74 (d, J=1.5 Hz, 1H), 9.26 (d, J=2.0 Hz, 1H)
