Acetic Acid → 2-Carbomethoxy-7-hydroxy-8-propylchromone

Participants

Reaction Steps

To a solution of 99.7 g (0.513 mole) of 2,4-dihydroxy-3-propylacetophenone and 72.7 g (0.77 mole) of dimethyl oxalate in 1 liter of dry dimethylformamide was added in portions 97 g (1.8 mmole) of sodium methoxide. After stirring for 4 hours, 1.8 l of acetic acid was added and stirring was continued for 4 days. The reaction mixture was heated in a steam bath for four hours and evaporated to dryness. Water was added to the residue and the mixture was heated to boiling. A solid was filtered off and recrystallized from ethanol to give 89.8 g of the title compound, mp. 222°-224°. Structure assignment was supported by nmr and infrared spectra.

Provenance & Evidence