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Updated: May 5, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Solvent promoted reversible cyclometalation in a tethered NHC iridium complex
James E Wheatley1, C André Ohlin, Adrian B Chaplin
1Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK. a.b.chaplin@warwick.ac.uk.
Abstract:
Reaction of [Ir(COD)(py-I(t)Bu)](+) (py-I(t)Bu = 3-tert-butyl-1-picolylimidazol-2-ylidene) with acetonitrile results in reversible intramolecular C-H bond activation of the NHC ligand and formation of [Ir(η(2):η(1)-C8H13)(py-I(t)Bu')(NCMe)](+). Coordinated COD acts as an internal hydride acceptor and acetonitrile coordination offsets the otherwise unfavourable thermodynamics of the process.
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