To 8 ml of DMF was added 4-iodo-1H-indazol-3-amine (690 mg, 2.65 mmol) and 3-ethynylaniline (480 mg, 1.5 eq., 4.1 mmol). Following that, Bis(triphenylphosphine) palladium(II) dichloride (180 mg, 0.25 mmol, 10 mol %), Copper Iodide (100 mg, 0.52 mmol, 20 mol %), Triphenylphosphine (18 mg, 0.07 mmol, 3 mol %) and 8 ml of triethylamine was added. Nitrogen was bubbled through the reaction mixture for 15 minutes. The reaction was then set with a reflux condenser, set under nitrogen atmosphere, and heated at 60° C. for 2 hours. After that, the reaction was cooled to room temperature and 40 ml of ethyl acetate was added. The organic layer was extracted with aqueous sodium bicarbonate (3×40 ml), brine (3×40 ml), dried using anhydrous sodium sulfate, loaded onto silica and columned to give 4-((3-aminophenyl)ethynyl)-1H-indazol-3-amine.
