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Updated: May 29, 2025
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Using Common Alcohols to Transform N-H NHC-Palladium Complexes into Reactive Catalysts for the Suzuki-Miyaura
Alexandra J S Larson1, Sydney K F Pettit1, Rachel N Owens1
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States.
Abstract:
We demonstrate that the generation of mixed NHC/phosphinite Pd catalysts from 2-phosphinoimidazole ligands using bulky alcohols provides highly active Pd catalysts for cross-coupling reactions. Mechanistic studies suggest that the rapid loss of bulkier phosphinites from the precatalyst leads to more rapid oxidative addition. These catalysts demonstrate a broad substrate scope in Suzuki-Miyaura reactions with aryl chlorides. Conversion of a methanol-derived catalyst into a tert-butanol-derived catalyst in situ also enables selective and sequential cross-coupling of bromochloroarenes.
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