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Updated: Oct 15, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Electrostatic effects in N-heterocyclic carbene catalysis: revealing the nature of catalysed decarboxylation
Zhipeng Pei1, Qinyu Qiao2, Cunxi Gong2
1Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia. michelle.coote@anu.edu.au.
Abstract:
Quantum chemistry is used to investigate the nature of protonated N-heterocyclic carbene (NHC·H+) catalysed decarboxylation recently reported by Zhang et al. (ACS Catal., 2021, 11, 3443-3454). Our results show that there are strong electrostatic effects within the NHC·H+ catalysed decarboxylation, and these dominate hydrogen bonding. At the same time, energy decomposition analyses and comparison between the original NHC·H+ catalyst and a truncated form reveal that stabilizing dispersion interactions are also critical, as is induction. We also show that the electrostatic effects and their associated catalytic effects can be further enhanced using charged functional groups.
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