Novel Hybrid Prins/Aza-Prins Oxocarbenium/N-Acyliminium Cascade Expedient Access to Complex Indolizidines

Mathéo Berthet (1) , Alice Beauseigneur (1) , Charlotte Moine (1) , Catherine Taillier (1) , Mohamed Othman (1) , Vincent Dalla (1)

1 URCOM - Unité de Recherche en Chimie Organique et Macromoléculaire

Heavy silyl enol ethers (mostly TIPS and TBS) combine with cyclic N-alkenyl N-acyliminium salts generated in situ from their N,O-acetal precursors, to furnish highly functionalized indolizidines through an unprecedented double Mukaiyama–Mannich–Prins cascade transformation. This novel cascade annulation process demonstrates a promising scope, and takes place mostly catalytically with interesting stereocontrol. Furthermore, an appealing facet of this chemistry is emphasized with a bicatalytic approach by which the Mannich–Prins cascade follows a Ru-catalyzed N-allylamide to N-(E)-propenyl isomerization of the aminal counterpart in a one-pot operation. © 2018 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim

Keywords: cascade reaction; indolizidines; N-acyliminium ion; oxacarbenium ion; Prins cyclisation

Domains: Chemical Sciences

Mathéo Berthet, Alice Beauseigneur, Charlotte Moine, Catherine Taillier, Mohamed Othman, et al.. Novel Hybrid Prins/Aza-Prins Oxocarbenium/N-Acyliminium Cascade Expedient Access to Complex Indolizidines. Chemistry - A European Journal, 2018, 24 (6), pp.1278-1282. ⟨10.1002/chem.201705949⟩. ⟨hal-02413309⟩