Effect of Electronic Enrichment of NHCs on the Catalytic Activity of [Pd(NHC)(acac)Cl] in Buchwald–Hartwig Coupling

A series of [Pd(NHC)(acac)Cl] (NHC = N-heterocyclic carbene) complexes have been synthesized and characterized to investigate the electronic and steric effects of NHC ligands in catalysis. Their reactivity in Buchwald–Hartwig coupling has been explored and compared with that of their nonmethoxylated congeners. Combining the optimal steric and electronic properties, [Pd(IHeptOMe)(acac)Cl] performed excellently in the palladium-catalyzed amination of deactivated aryl chlorides with various anilines.

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