63234-80-0

41078-70-0

63234-80-0

The general procedure for the synthesis of 3-(2-chloroethyl)-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one from 3-(2-chloroethyl)-2-methyl-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-one is as follows: 28 g of 3-(2-chloroethyl)-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one obtained in step A) was dissolved in 90 mL 6N hydrochloric acid. -a]pyrimidin-4-one was dissolved in 90 mL of 6N hydrochloric acid, followed by the addition of 2.8 g of 10% palladium carbon catalyst to the solution. The reaction mixture was subjected to 35 psi hydrogen pressure and hydrogenated at room temperature with stirring for 8 hours. Upon completion of the reaction, the mixture was filtered through diatomaceous earth (Cellite) to remove the catalyst. The filtrate was concentrated under reduced pressure to give a residue. To the residue was added 200 mL of isopropanol and the mixture was stirred. The precipitated solid was collected by filtration and dried to give 25.1 g of the target product 3-(2-chloroethyl)-2-methyl-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-one as white crystals in 90% yield.