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Updated: Aug 20, 2025

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Enantioselective Ugi and Ugi-azide reactions catalyzed by anionic stereogenic-at-cobalt(III) complexes
Bing-Bing Sun1, Kun Liu1, Quan Gao2
1Department of Applied Chemistry, Anhui Agricultural University, Hefei, 230036, China.
Abstract:
Ugi reactions and related variations are proven to be atom and step-economic strategies for construction of highly valuable peptide-like skeletons and nitrogenous heterocycles. The development of structurally diverse range of novel catalytic systems and the discovery of new approaches to accommodate a broader scope of terminating reagents for asymmetric Ugi four-component reaction is still in high demand. Here, we report a strategy that enables enantioselective Ugi four-component and Ugi-azide reactions employing anionic stereogenic-at-cobalt(III) complexes as catalysts. The key nitrilium intermediates, generated through the nucleophilic addition of isocyanides to the chiral ion-pair which consists of stereogenic-at-cobalt(III) complexes counteranion and a protonated iminium, are trapped by either carboxylic acids or in situ-generated hydrazoic acid, delivering α-acylamino amides and α-aminotetrazoles in good to excellent enantioselectivities (up to 99:1 e.r.).
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