Hydrochloric Acid → Ethyl 5-hydroxy-8-(2-methoxyethyl)-7-oxo-2-phenyl-7,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylate

Participants

Reaction Steps

50 ml. of NaOEt (0.5 g. Na -0.021 mole) was added to 3.4 g. (0.021 mole) of ethyl malonate and stirred 10 minutes, then evaporated to dryness. DMF was added until a solution was achieved and then 3.2 g. (0.011 mole) of 1-(2-methoxyethyl)-7-phenyl-2H-pyrimido[4,5-d][1,3]oxazine-2,4(1H)-dione was added and this mixture refluxed 2 hours. The chilled reaction was poured into dilute HCl and the ensuing precipitate filtered off and rinsed with water. Recrystallization from ethyl acetate gave 3.5 g. of the title product--m.p. 178°-179° C.

Provenance & Evidence