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Updated: Jun 12, 2025
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
C-H Activation and Hydrogen Isotope Exchange of Aryl Carbamates Using Iridium(I) Complexes Bearing Chelating
Renan Zorzatto1, Paul T Mulrainey1, Marc Reid1
1Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, G1, Scotland, 1XL, U.K.
Abstract:
Hydrogen isotope exchange (HIE) via C-H activation constitutes an efficient method for the synthesis of isotopically-enriched compounds, which are crucial components of the drug discovery process and are extensively employed in mechanistic studies. A series of iridium(I) complexes, bearing a chelating phosphine-N-heterocyclic carbene ligand, was designed and synthesized for application in the catalytic HIE of challenging N- and O-aryl carbamates. A broad range of substrates were labeled efficiently, and applicability to biologically-relevant systems was demonstrated by labeling an ʟ-tyrosine-derived carbamate with excellent levels of deuterium incorporation. Combined theoretical and experimental studies unveiled intriguing mechanistic features within this process, in comparison to C-H activation and hydrogen isotope exchange catalyzed by monodentate Ir(I) NHC/phosphine complexes.
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