Mechanism of benzoquinone-promoted palladium-catalyzed oxidative cross-coupling reactions.
This communication describes mechanistic studies of the Pd-catalyzed oxidative cross-coupling of benzo[h]quinoline with simple arenes. Through a series of experiments, including determination of the order of the reaction in various reagents, H/D exchange studies, kinetic isotope effect investigations, and the evaluation of electronic effects, we propose a detailed mechanism for these reactions. Importantly, this mechanism explains the key role of benzoquinone in these transformations; in addition, it provides insights that allow the rational tuning of reaction conditions to control the chemoselectivity of Ar-Ar' coupling.
Hull
Kami L
KL
Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, USA.
Sanford
Melanie S
MS