title: Addition of electrophilic radicals to 2-benzyloxyglycals: synthesis and functionalization of fluorinated α-C-glycosides and derivatives.
abstract: A new method for the synthesis of fluorinated α-C-glycosides is described. The reactions between highly electrophilic radicals (fluorinated or unfluorinated) and a 2-benzyloxyglucal or galactal provide 2-keto-D-arabino- or 2-keto-D-lyxo-hexopyranosides through an addition/fragmentation process. Sodium borohydride mediated or Meerwein-Ponndorf-Verley (MPV) reduction of these compounds provides α-C-glycosides that feature appropriate anchoring groups for further synthetic elaboration. The presence of CF2 CO2 iPr or CF2 Br groups at the pseudo-anomeric position allows efficient reduction/olefination or Br/Li-exchange/nucleophilic-addition sequences. These transformations open the way for the synthesis of fluorinated C-glycosidic analogues of glycoconjugates.
authors: Normandie Université, COBRA, UMR 6014 et FR 3038, Université Rouen, INSA Rouen, CNRS, 1 rue Tesnière, 76821 Mont Saint-Aignan Cedex (France).
authors: Sophie
authors: S
authors: Colombel
authors: Nathalie
authors: N
authors: Van Hijfte
authors: Thomas
authors: T
authors: Poisson
authors: Eric
authors: E
authors: Leclerc
authors: Xavier
authors: X
authors: Pannecoucke
mesh_terms: D000475:Alkenes / Q000737:chemistry; D001894:Borohydrides / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry*; D005690:Galactose / Q000031:analogs & derivatives / Q000737:chemistry; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D054879:Halogenation; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D001894:Borohydrides; D005609:Free Radicals; D006027:Glycosides; C002038:galactal; C025364:sodium borohydride; D005690:Galactose
keywords: fluorine; glycomimetics; olefination; radicals; reduction