Atom-Economic Catalytic Direct Substitution of N,O-Acetals with Simple Ketones

Bahria Touati (1) , Abderrahman El Bouakher (1) , Mohamed Salah Azizi (1) , Catherine Taillier (1) , Raja Ben Othman (2) , Malika Trabelsi-Ayadi (3) , Sylvain Antoniotti (4) , Elisabet Duñach (4) , Vincent Dalla (1)

1 URCOM - Unité de Recherche en Chimie Organique et Macromoléculaire
2 ESSTHS - Ecole Supérieure des Sciences et de Technologie de Hammam Sousse
3 Université de Carthage - University of Carthage
4 ICN - Institut de Chimie de Nice

A general and powerful catalytic protocol for the direct amidoalkylation of simple enolizable ketones is described, with use of the Lewis superacid Sn(NTf2)4 as a catalyst under thermal conditions. A complete and rational study directed towards the development of efficient conditions for the coupling of a wide range of reaction partner combinations, including the most recalcitrant ones, is presented. The synthetic potential of the reaction is demonstrated through the use of a large set of both carbonyl and N,O-acetalic substrates, providing the corresponding amidoalkylated ketones in 49–99 % yield, by using very low catalyst loadings (≤ 1 mol-%). © 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim

Keywords: Amidoalkylation; Enols; Ketones; Lewis acids; N; O-acetals; Tin

Domains: Chemical Sciences

Bahria Touati, Abderrahman El Bouakher, Mohamed Salah Azizi, Catherine Taillier, Raja Ben Othman, et al.. Atom-Economic Catalytic Direct Substitution of N,O-Acetals with Simple Ketones. European Journal of Organic Chemistry, 2017, 2017 (30), pp.4445-4460. ⟨10.1002/ejoc.201700530⟩. ⟨hal-02413313⟩