4-Chloro-5-iodopyrimidine (200 mg, 0.832 mmol) and cesium carbonate (542 mg, 1.664 mmol) were added to a pressure resistant reaction tube. The solid was dissolved in N,N-dimethylformamide (DMF, 2 mL) and methanol (0.083 mL, 2.057 mmol) was subsequently added to the solution. The reaction tube was sealed and the reaction was heated at 90 °C overnight, after which it was cooled to room temperature. The reaction mixture was filtered, diluted with water (5 mL) and extracted with ethyl acetate (EtOAc). The organic phase was washed twice with 10% aqueous lithium chloride, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The resulting crude product was used directly in the next step of the reaction (70 mg, 25.7% yield). Mass spectrum (electrospray ionization, ES): m/z = 236.80 [M + H]+. NMR hydrogen spectrum (400 MHz, DMSO-d6) δ ppm 8.86 (1H, single peak), 8.72 (1H, single peak), 3.98 (4H, single peak).
