A mixture of 3-dimethylamino-1-(2-chloro-3-pyridyl)-2-propen-1-one (810 mg, 3.86 mmol), 3-ethoxycarbonyl-phenyl-guanidine nitrite (1.07 g, 3.96 mmol), lithium hydroxide (105 mg, 4.38 mmol) in 2-butanol (20 mL) is heated to reflux overnight. The reaction mixture is cooled to room temperature, the solvent is removed and water (40 mL) is added. The solid is collected by filtration and washed with water, isopropanol and dried to give N-[3-ethoxycarbonyl-phenyl]-4-(2-chloro-3-pyridyl)-2-pyrimidineamine (1.15 g); ESI-MS (m/z): 355.1 (M++H).
