Synthesis of 2-Hydroxy-3-methyl-2-hexen-4-olid

Article abstract of DOI:10.1002/hlca.19870700214

The title compound 13a, a substance used in food-flavoring, was synthesized in 89percent overall yield, starting from methyl 2-hydroxy-3-butenoate (3a).The key step in this transformation is the isomerization of the C=C bond in 3a which yielded methyl 2-oxobutanoate as an intermediate.The latter underwent a self-condensation yielding 2-hydroxy-4-(methoxycarbonyl)-3-methyl-2-hexen-4-olid (11a), which, after hyrolysis and decarboxylation, gave 13a.In addition the syntheses of five other compounds related to 13a are reported.