To toluene 2.1 mL solution of tert-butyl 4-bromo-2-(4-fluoroanilino)benzoate 0.1 g were added ethanol 0.60 mL, water 0.30 mL, 1-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole 84 mg, sodium hydrogen carbonate 69 mg and tetrakis(triphenylphosphine)palladium(0) 16 mg at room temperature, and it was heated and refluxed for 4 hours. After the reaction mixture was cooled to room temperature, toluene and saturated sodium hydrogen carbonate aqueous solution were added to it. The organic layer was separated and collected,dried over anhydrous magnesium sulfate after washing with saturated sodium chloride aqueous solution, and the solvent was removed under reduced pressure. The obtained residue was refined by silica gel column chromatography [Trikonex company, Flash Tube 2008, eluent; hexane:ethyl acetate=10:1] to give tert-butyl 2-(4-fluoroanilino)-4-(1-methyl-1H-indol-5-yl)benzoate.
