To the nitrogen degassed solution of 1-(2-iodophenyl)urea (1.31 g, 5 mmol, 1 eq), 3-ethynylaniline (0.8 mL, 1.5 eq), triphenylphosphine (32.8 mg, 0.025 eq), and triethylamine (2.1 mL, 3 eq) in anhydrous DMF (12.5 mL) was added copper(I) iodide (190.4 mg, 0.2 eq) and bis(triphenylphosphine)palladium(II) dichloride (351 mg, 0.1 eq). After the reaction mixture was stirred at room temperature for 10 minutes, it was diluted with ethyl acetate, washed sequentially with aqueous ammonium chloride, saturated aqueous sodium bicarbonate, brine, and lastly dried with anhydrous sodium sulfate. The upper solution was decanted, concentrated, and the solid mixture was subject to a gradient column chromatography (EtOAc-Hex 1:2 to MeOH-EtOAc 1:9) to give 1-{2-[(3-aminophenyl)ethynyl]phenyl}urea as a brown solid in amount of 1.26 g.
