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Updated: Jun 15, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
A simple N-heterocyclic carbene for the catalytic up-conversion of aldehydes into stoichiometric super electron
Nadhrata Assani1, Ludivine Delfau2, Preslav Smits2
1Aix Marseille Univ, CNRS, ICR, Institut de Chimie Radicalaire, Faculté de Pharmacie 13005 Marseille France julie.broggi@univ-amu.fr.
Abstract:
Catalytic amounts of 1,3-di(methyl)imidazole-2-ylidene, one of the simplest and most prototypical N-heterocyclic carbenes, can up-convert aldehydes into powerful stoichiometric sources of electrons (Super Electron Donors) for reductive transformations of iodoaryls (E red < -2 V). In particular, the hydroarylation of 1,1'-diarylethylenes, which may require high temperatures and inherently generate stoichiometric amounts of oxidized waste, was performed at room temperature, with the concomitant formation of esters as oxidized co-products.
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