Synthesis of β,γ-disubstituted-γ-lactones through a Johnson–Claisen rearrangement: a short route to xylobovide,nor-canadensolide,canadensolide, sporothriolide and santolinolide

The Johnson–Claisen rearrangement of allyl alcohols with chiral vicinal diol functionality was employed to access chiral β,γ-disubstituted-γ-lactones in high enantio- and diastereoselectivity. These were efficiently converted into nor-canadensolide, the advanced γ-(lactone–lactol) intermediate for xylobovide, canadensolide and sporothriolide and the lactone moiety of the santolinolides.