| Abstract
| - Under standard hydroboration-oxidation conditions, the dihydropyrans 4 underwent a highlystereocontrolled tandem reaction, involving the expected hydration of the double bond togetherwith the reduction of the ketal moiety. This unprecedented transformation gives rise to a short,[4 + 2]-based synthetic route to (±)-β-C-naphthyl-2-deoxyglycosides 5, which allows a significantstructural and functional diversity at C-6. We thus described the first synthesis of (±)-C-aryl-6-fluoro and -6,6-difluoro olivosides, via the allylic mono- and difluorides produced by regioselectivefluorination of, respectively, hydroxyalkyl and oxoalkyl dihydropyran derivatives.
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