Convenient preparative methods for N‐aryl‐γ‐pyridones from γ‐pyrones

Abstract
2‐Hydroxymethyl‐5‐methoxy‐4‐H‐pyran‐4‐one (1) reacts with aniline and six aniline derivatives in very dilute aqueous hydrochloric acid at reflux temperature to give the N‐aryl‐γ‐pyridone. A second procedure utilizes the aromatic amine hydrochloride by reacting it with 1 in aqueous medium at reflux temperature. p‐Nitroaniline hydrochloride and 1 give the N‐aryl‐γ‐pyridone in 65% yield, as opposed to 12% from the dilute acid procedure.