2-Amino-4,6-dichloro-pyrimidine-5-carbaldehyde

56-09-7

5604-46-6

Example 1: This example describes the synthesis of 2-amino-4,6-dichloropyrimidine-5-carbaldehyde using 2-amino-4,6-dihydroxypyrimidine as starting material. The procedure was as follows: absolute DMF (210 mL, 1.38 mol) was added dropwise to an ice-cold POCl3 solution (900 mL) over 20 minutes under ice bath conditions. After removal of the ice bath, powdered 2-amino-6-hydroxypyrimidin-4(3H)-one (150 g, 1.17 mol) was added over 20 min. Subsequently, the reaction mixture was heated to 100 °C and the reaction was stirred at this temperature for 3-4 hours. Upon completion of the reaction, the solution was cooled to room temperature and slowly poured into a pre-prepared ice-water mixture (diluted to 10 L from 4 L of crushed ice with water). The resulting aqueous solution was heated to 50 °C and stirring was continued for 2 hours. Finally, the mixture was placed in a refrigerator overnight and the precipitate was collected by filtration and dried to obtain the target product 2-amino-4,6-dichloropyrimidine-5-carbaldehyde (160 g, 71% yield).