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Updated: Jan 18, 2026
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Organocatalysis promoted by 1,2,3-triazolylidenes (MICs): carbenes which make a difference
Fan Gao1, Xiaoyu Yan1, Guy Bertrand2
1Key Laboratory of Advanced Light Conversion Materials and Biophotonics, School of Chemistry and Life Resources, Renmin University of China, Beijing, 100872, China. yanxy@ruc.edu.cn.
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N-Heterocyclic carbenes (NHCs) hold a unique significance in organometallic catalysis and are powerful organocatalysts for a variety of organic transformations involving crucial intermediates such as Breslow intermediates (BIs), deprotonated BIs (BI-s), ketyl radicals (KRs), and acyl azoliums (AAs). To address the remaining challenges facing reactions catalyzed by NHCs, non-classical stable carbenes, namely 1,2,3-triazolylidenes (MICs), cousins of NHCs, have shown great potential. MICs share similar features with typical NHCs but possess unique characteristics, such as enhanced σ-donor ability and absence of dimerization. Consequently, they have emerged as effective metal-free carbene catalysts for various chemical transformations. This review provides an overview of the fundamental characteristics of 1,2,3-triazolylidenes, along with the significant organic synthetic applications of these carbenes.
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