A straightforward and flexible [4 + 2] route to beta-C-naphthyl-2-deoxy-glycosides through tandem hydroboration-ketal reduction: de novo access to C-naphthyl-6-fluoro and 6,6-difluoro 2-deoxyglycosides.
[reaction: see text] Under standard hydroboration-oxidation conditions, the dihydropyrans 4 underwent a highly stereocontrolled tandem reaction, involving the expected hydration of the double bond together with the reduction of the ketal moiety. This unprecedented transformation gives rise to a short, [4 + 2]-based synthetic route to (+/-)-beta-C-naphthyl-2-deoxyglycosides 5, which allows a significant structural 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 regioselective fluorination of, respectively, hydroxyalkyl and oxoalkyl dihydropyran derivatives.
Nguyen
Quang Vu
QV
UCO2M, UMR CNRS 6011, Université du Maine, 72085 Le Mans Cedex 9, France.
Leconte
Stéphane
S
Brown
Eric
E
Grée
Danielle
D
Grée
René
R
Dujardin
Gilles
G
D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction
D006027:Glycosides