Diethyl (ethoxymethylene)malonate → HCID 21408193, compound

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of 12 g (0.067 mole) of 6-fluoro-2-methyl-4-oxo-1,2,3,4-tetrahydroquinoline from example 4 and 14.8 g (0.070 mole) of diethyl ethoxymethylenemalonate was heated gradually to 160° to 180° C. while removing the ethanol generated by distillation. After 0.5 hour the mixture was cooled to 60° C., and 30 g of polyphosphoric acid was added. This mixture was heated gradually to 150° to 160° C. and maintained at 155° to 160° C. for 5 to 10 minutes. Following cooling, water was added, and the mixture was kneaded to produce an orange powder which was separated by filtration. Recrystallization from a mixture of 500 ml of 95% ethanol and 100 ml of glacial acetic acid gave a yellow product, ethyl 6,7-dihydro-1,7-dioxo-9-fluoro-5-methyl-1H,5H-benzo[ij]quinolizine-2-carboxylate, m.p. 262°-265° C.

Provenance & Evidence