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Updated: Jun 26, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Direct access to 2-imidazolines from unactivated alkenes
Stefanie Schiele1, Ann-Sophie K Paschke1, Giorgia Romiti1
1Laboratorium für Organische Chemie ETH Zürich Vladimir-Prelog-Weg 3, HCI 8093 Zürich Switzerland bill.morandi@org.chem.ethz.ch.
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The formation of carbon-nitrogen bonds is crucial for the discovery of pharmaceuticals, materials, and agrochemicals. Nitrogen-containing functional groups, especially heterocycles, are common motifs in biologically active compounds. Among these, 2-imidazolines have emerged as important scaffolds with their own class of biological targets. Herein, we report the development of an oxidative amination process to directly convert unactivated alkenes into 2-imidazolines. The combination of ammonia and a commercially available hypervalent iodine reagent achieves the cleavage of the carbon-carbon double bond. Subsequent interception of the resulting imine by ethylenediamine and oxidation furnishes 2-imidazolines in high yields. The reaction is rapid and tolerates a wide range of functional groups, showcasing its potential for late-stage diversification of complex molecules.
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