Preparation of 5-aryl-3-oxo-delta-lactones by the potassium carbonate-promoted condensation of aromatic aldehydes and ethyl acetoacetate in ethanol

摘要

5-Aryl-3-oxo-delta-lactones (6-aryl-dihydro-2H-pyran-2,4(3H)-diones) were prepared by the potassium carbonate-promoted condensation of aromatic aldehydes and ethyl acetoacetate in absolute ethanol. Benzaldehyde and substituted benzaldehydes bearing an alkoxy group (2 or 3 position), a chlorine atom (2, 3, or 4 position), a nitro group (3 or 4 position), a cyano group (4 position), or an acetyl group (4 position) react in high yields under these conditions.