Lävulinsäureanilid und 5‐Hydroxy‐5‐methyl‐1‐phenyl‐2‐pyrrolidon

Abstract

Abstract The hitherto unknown tautomer of levulinic acid anilide (Ia), 5‐hydroxy‐5‐methyl‐1‐phenyl‐2‐pyrrolidone (IIa), has been obtained by filtration of a chloroform solution of I a through acid ion‐exchange columns. Ia and IIa show typical differences in NMR., IR. and MS. that can be used for their detection and determination in mixtures. Both tautomers are stable at room temperature in solid state and in neutral solutions but are equilibrated in acidic and basic solutions.