A convenient route to 2,6-dialkyl-2,3-dihydro-4H-pyran-4-ones via oxidative cleavage of protected 1-(2-oxoalkyl)-cyclopropanols. Synthesis of (±)-hepialone and its natural congener

An efficient strategy for the synthesis of 2,6-dialkyl-2,3-dihydro-4H-pyran-4-ones has been developed, the key steps of which are oxidative cleavage of the three-membered rings of 1-(2-oxoalkyl)-cyclopropanols and acid-promoted cyclization of the resulting β-hydroxyketones.