2-Aminopyridine → 3-(2-Chloroethyl)-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one

Participants

Reaction Steps

40 g of 2-aminopyridine and 75 ml of 3-acetyl-4,5-dihydro-2(3H)-furanone were added to 1.0 L of toluene, and then 200 ml of phosphorus oxychloride was added thereto dropwise over 1 hour. The resulting mixture was slowly heated and refluxed for 5 hours. The reaction mixture was concentrated under a reduced pressure and the residue was poured to a mixture of ice and ammonia water. The resulting solid was extracted with 1.0L of dichloromethane, dried and filtered. The filtrate was concentrated under a reduced pressure to remove dichloromethane and 500 ml of isopropanol was added to the residue. The resulting crystal was filtered, washed and dried to obtain 48.1 g of the title compound as a off-white crystal (yield: 52%).

Provenance & Evidence