To a mixture of 5-bromo-2-(phenylsulfonyl)pyridine (6.00 g), ethynylbenzene (2.87 mL), dichlorobis(triphenylphosphine)palladium (II) (140 mg) and CuI (38 mg) in DMF (90 mL) was added triethylamine (8.42 mL) and the mixture was stirred at 60° C. for 1 h. The reaction mixture was diluted with EtOAc, washed with water and brine, dried over sodium sulfate, evaporated in vacuo. The residue was purified by silica gel column chromatography (CHCl3 to CHCl3-EtOAc 10:1) to give 5-(phenylethynyl)-2-(phenylsulfonyl)pyridine (6.33 g) as a solid.
