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Updated: Nov 1, 2025

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
N-Heterocyclic Iod(az)olium Salts - Potent Halogen-Bond Donors in Organocatalysis
Andreas Boelke1, Thomas J Kuczmera1, Enno Lork2
1Institut für Organische und Analytische Chemie, Universität Bremen, Leobener Straße NW2C, 28359, Bremen, Germany.
Abstract:
This article describes the application of N-heterocyclic iod(az)olium salts (NHISs) as highly reactive organocatalysts. A variety of mono- and dicationic NHISs are described and utilized as potent XB-donors in halogen-bond catalysis. They were benchmarked in seven diverse test reactions in which the activation of carbon- and metal-chloride bonds as well as carbonyl and nitro groups was achieved. N-methylated dicationic NHISs rendered the highest reactivity in all investigated catalytic applications with reactivities even higher than all previously described monodentate XB-donors based on iodine(I) and (III) and the strong Lewis acid BF3 .
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