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Updated: Aug 22, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
N-heterocyclic carbenes: reagents, not just ligands!
Vijay Nair1, Santhamma Bindu, Vellalath Sreekumar
1Organic Chemistry Division, Regional Research Laboratory (CSIR), Trivandrum 695 019, India. vijaynair_2001@yahoo.com
Abstract:
The unique properties of N-heterocyclic carbenes (NHCs) have attracted much attention, mainly from theorists and organometallic chemists, the latter using them impressively as ligands for metals. Less well known, however, has been their suitability as excellent catalysts and nucleophilic reagents. Transesterification, nucleophilic aromatic substitution, and cycloaddition reactions are examples in which NHCs can play an important role. Asymmetric reactions using catalytic amounts of chiral NHCs are an efficient approach to optically active compounds. This minireview focuses on this aspect of the chemistry of NHCs.
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