Diethyl (ethoxymethylene)malonate → Diethyl {[(4-oxo-4H-1-benzopyran-3-yl)amino]methylene}propanedioate

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-aminochromone (8.0 g, 0.05 mole) and diethyl ethoxymethylenemalonate (17.3 g, 0.08 mole) was heated under nitrogen at 140° C. for 2.5 hrs. The reaction mixture was cooled. The product, which crystallized out was filtered off and triturated with petroleum ether. Recrystallization from ethyl acetate - absolute ethanol gave white crystals (10.3 g, 62.5%), m.p. 155°-157° C.

Provenance & Evidence