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Updated: Jan 27, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Gold(III)-Substituted Carbenes
Rui Wei1, Shuo Li1, Nina Albouy2
1Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), CNRS/Université de Toulouse, 31062 Toulouse, France.
None:
The Au(III)-substituted diazo compounds (N^C^C)AuC(N2)R (R = Dmp = 2,6-dimesitylphenyl and SiMe3) 1 and 6 were synthesized by reacting the (N^C^C)AuCl precursor with the corresponding lithiated diazo compounds. Dinitrogen extrusion was then promoted by UV-vis irradiation. The (N^C^C)Au-C-Dmp carbene 3 undergoes intramolecular C-H insertion followed by β-H elimination, affording a phenanthrene derivative and the Au(III) hydride complex (N^C^C)AuH. Steric shielding prevents intermolecular carbene trapping. The related (N^C^C)Au-C-SiMe3 carbene 7 was generated and characterized by in crystallo photolysis. In solution, it displays intermolecular reactivity typical for triplet as well as singlet carbenes, such as H atom abstraction and carbene-type couplings with isocyanides. DFT calculations shed light on the structure, bonding, and reactivity of these Au(III)-substituted carbenes.
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