Nitrogen was bubbled through a mixture of ethyl 2-(5-acetamido-4-iodo-3-phenyl-pyrazol-1-yl)acetate (18.6 g, 45 mmol), phenyl acetylene (9.2 g, 90 mmol), copper iodide (860 mg, 4.5 mmol), triethylamine (200 mL) and DMF (75 mL) for 15 min. Bis(triphenylphosphine)palladium(II) dichloride (1.6 g, 2.25 mmol) was added and the reaction mixture was stirred at 90° C. under nitrogen for 4.5 h. The reaction mixture was cooled to room temperature, diluted with ethyl acetate and water. The organic phase was washed with water and brine, dried (MgSO4), filtered and concentrated in vacuo. The residue was partially purified by column chromatography (silica gel, CH2Cl2, then isohexane/ethyl acetate 1:1 followed by CH2Cl2/ethyl acetate 9:1 to 8:2), then triturated with diethyl ether to provide the title compound as a solid (13 g).
