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Updated: Jul 10, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
High-yielding palladium-catalyzed intramolecular alkane arylation: reaction development and mechanistic studies
Marc Lafrance1, Serge I Gorelsky, Keith Fagnou
1Center for Catalysis Research and Innovation, University of Ottawa, Department of Chemistry, 10 Marie Curie, Ottawa, Ontario, Canada K1N 6N5.
Abstract:
Palladium-catalyzed alkane arylation reactions with aryl halides are described for the preparation of 2,2-dialkyl-dihydrobenzofuran substrates. These reactions occur in excellent yield and very high selectivity for the formation of one sole product arising from a reaction at nearby methyl groups. Mechanistic and computational studies point to the involvement of a concerted, inner-sphere palladation-deprotonation pathway that is enabled by the presence of three-center agostic interactions at the transition state. This mechanism accurately predicts the experimentally observed kinetic isotope effect as well as the site selectivity and should be useful in the design of new reactions and catalysts.
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