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Updated: Mar 9, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Synergistic Diastereo- and Enantioselective Functionalization of Unactivated Alkyl Quinolines with α,β-Unsaturated
Marta Meazza1, Fernando Tur1, Niels Hammer1
1Department of Chemistry, Aarhus University, 8000, Aarhus C, Denmark.
Abstract:
A novel alkyl functionalization of unactivated alkyl quinolines has been developed combining InCl3 activation with organocatalytic activation of α,β-unsaturated aldehydes in a synergistic fashion. The reaction proceeds in a highly stereoselective manner as a sequence involving two consecutive synergistic catalytic cycles (Lewis acid- and iminium ion-catalyzed) and requires neither pre-activated alkyl quinoline substrates with electron-withdrawing substituents nor highly activated electrophiles. The reaction provides selectively double- or mono-addition products in good yields and high to excellent stereoselectivities. Furthermore, based on spectroscopic and labelling experiments, the mechanisms for the reactions are discussed.
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