A solution of N4-(1-methylpiperidin-4-yl)-5-phenylpyridine-2,4-diamine (0.050 g, 0.17 mmol), 2-bromo-5-cyanopyrazine (0.022 g, 0.12 mmol), BINAP (0.003 g, 0.01 mmol), sodium tert-butoxide (0.016 g, 0.16 mmol), tris(dibenzylideneacetone)dipalladium chloroform complex (0.005 g, 0.01 mmol) in toluene (0.7 mL) was stirred at r.t. under nitrogen for 10 min before being heated under microwave irradiation for 30 min at 90° C. The crude reaction mixture was purified by ion exchange on SCX-II acidic resin (0.5 g) eluting with methanol/dichloromethane (1/1), then 2M ammonia-methanol. The basic fractions were combined and the solvent was removed in vacuo. The crude mixture was purified by preparative thin layer chromatography eluting with methanol/dichloromethane (1/9) to give the desired compound as a yellow solid (0.008 g, 17%).
