Insight into the Ferrier rearrangement by combining flash chemistry and superacids

Naresh Bhuma (1) , Ludivine Lebedel (1) , Hiroki Yamashita (2) , Yutaka Shimizu (2) , Zahra Abada (1) , Ana Ardá , Jérôme Désiré (1) , Bastien Michelet (1) , Agnès Martin-Mingot (1) , Ali Abou-Hassan (3) , Masahiro Takumi (2) , Jérôme Marrot (4) , Jesús Jiménez-Barbero , Aiichiro Nagaki (2) , Yves Blériot (1) , Sebastien Thibaudeau (1)

1 IC2MP [Poitiers] - Institut de chimie des milieux et matériaux de Poitiers [UMR 7285]
2 Kyoto University
3 PHENIX - PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX
4 ILV - Institut Lavoisier de Versailles

The transformation of glycals into 2,3-unsaturated glycosyl derivatives, reported by Ferrier in 1962, is supposed to involve an α,β unsaturated glycosyl cation, an elusive ionic species that has still to be observed experimentally. Herein, while combination of TfOH and flow conditions failed to observe this ionic species, its extended lifetime in superacid solutions allowed its characterization by NMRbased structural analysis, supported by DFT calculations. This allyloxycarbenium ion was further exploited in the Ferrier rearrangement to afford unsaturated nitrogen-containing C-aryl glycosides and C-alkyl glycosides under superacid and flow conditions respectively.

Domaines: Chimie organique

Naresh Bhuma, Ludivine Lebedel, Hiroki Yamashita, Yutaka Shimizu, Zahra Abada, et al.. Insight into the Ferrier rearrangement by combining flash chemistry and superacids. Angewandte Chemie International Edition, 2021, 60 (4), pp.2036-2041. ⟨10.1002/anie.202010175⟩. ⟨hal-03007376⟩