HCID 22758830, compound → HCID 22758826, compound

Participants

Reaction Steps

A stirred mixture of ethyl 6,7-dihydro-9-methoxy-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxylate (510 mgs.) in p-cymene (25 ml.) containing 10% palladium on carbon (150 mgs.) was refluxed for 7 hours. The mixture was flash evaporated to dryness and the residue extracted with boiling ethanol. The combined extracts were filtered and concentrated by boiling to give flocculent colorless needles of ethyl 9-methoxy-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxylate: 420 mgs. (81% yield), m.p. 211.5°-212°. An additional recrystallization from ethanol raised the m.p. to 217°-218°.

Provenance & Evidence