Synthesis
General procedure for the synthesis of 4-chloro-5-iodo-6-methylpyrimidine from 5-iodo-6-methylpyrimidin-4(1H)-one: trichlorophosphorus oxychloride (POCl3, 5.3 mL, 0.057 mol) was added to a suspension of 5-iodo-6-methylpyrimidin-4(1H)-one (3.4 g, 0.0144 mol) in diethylene glycol dimethyl ether (60 mL), the reaction The mixture was stirred at 90 °C for 2 hours. After completion of the reaction, it was cooled to room temperature and the reaction mixture was slowly poured into a 10% aqueous solution of potassium carbonate (K2CO3, 200 mL) and stirring was continued for 1 hour. The resulting solid product was collected by filtration, washed with water and dried to afford 4-chloro-5-iodo-6-methylpyrimidine (2.9 g, 79% yield).
References
[1] Patent: WO2011/92197, 2011, A1. Location in patent: Page/Page column 22
[2] Patent: US2012/28958, 2012, A1. Location in patent: Page/Page column 8
[3] Bioorganic and Medicinal Chemistry, 2013, vol. 21, # 11, p. 3090 - 3104