To a mixture of 5-methyl-7-phenylimidazo[5,1-f][1,2,4]triazin-2-amine hydrochloride (0.026 g, 0.10 mmol), 4-bromobenzenesulfonamide (0.026 g, 0.11 mmol), tris(dibenzylideneacetone)dipalladium (2.7 mg, 0.0030 mmol), (S)-(−)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (5.6 mg, 0.0090 mmol) and sodium t-butoxide (0.025 g, 0.23 mmol) was added dioxane (1 mL). The solution was heated with microwave radiation to 160° C. for 15 minutes. After cooling to room temperature, the solution was filtered, and silica gel (1 g) was added, followed by evaporation of the volatiles under reduced pressure. The pre-adsorbed solids were loaded into a solid loading cartridge and subjected to a gradient elution using ethyl acetate:hexanes (50:50) to ethyl acetate:hexanes (100:0) using a RediSep silica gel cartridge (4 g; ISCO). The appropriate fractions were combined and concentrated under reduced pressure to give 4-[(5-methyl-7-phenylimidazo[5,1-f][1,2,4]triazin-2-yl)amino]benzenesulfonamide (0.0015 g) as a yellow solid. MS m/z 381 (M+1).
