A suspension was formed with 3-(dimethylamino)-1-(furan-2-yl)prop-2-en-1-one (5.0 g, 30.3 mmol), guanidine hydrochloride (5.8 g, 60.7 mmol) and potassium carbonate (8.4 g, 60.9 mmol) in N,N-dimethylformamide (50 mL). The reaction mixture was stirred at 100 °C for 21 hours. After completion of the reaction, it was cooled to room temperature and diluted with ice water (250 mL). The resulting light brown solid 4-(2-furyl)pyrimidin-2-amine (4.19 g, 86% yield) was collected by filtration and washed with deionized water. The product was characterized by 1H NMR (400 MHz, DMSO-d6) and mass spectrometry (ESI): 1H NMR δ 6.66 (2H, br s), 6.68 (1H, dd, J = 2.0, 3.2 Hz), 6.88 (1H, d, J = 5.2 Hz), 7.17 (1H, dd, J = 0.8, 3.2 Hz), 7.88 (1H, dd, J = 0.8, 2.0 Hz), 8.28 (1H, d, J = 5.2 Hz); MS m/e (ESI) 162 (MH+).
