The reactivity of 4‐hydroxy‐6‐methyl‐2‐pyrone towards aliphatic saturated and α,β‐unsaturated aldehydes

Abstract

Abstract 4‐Hydroxy‐6‐methyl‐2‐pyrone (triacetic acid lactone) reacts at C‐3 with 2‐butenal and similar aldehydes by Michael addition. The nonisolated intermediates can undergo transformations in at least five different ways. On the contrary, reaction of the title pyrone with cinnamaldehyde occurs at the carbonyl group of the aldehyde.