Modulating Electronic Properties of N‐Heterocyclic Carbene Ligands: Effects on the Pd‐Catalyzed Buchwald–Hartwig Amination

N‐heterocyclic carbene (NHC) ligands featuring functional groups at remote positions allowing for electronic modifications were synthesized and their steric and electronic properties were investigated. The NHC ligands are found to possess comparable steric profiles while displaying similar, but varying electron donating capabilities. Palladium complexes coordinated to these ligands were synthesized, characterized, and investigated in the Buchwald–Hartwig Amination (BHA) of aryl chlorides under both strongly basic and weakly basic conditions. In both cases, we find that ligands possessing more electron donating substituents are more active in this transformation. We further report weakly basic conditions which gives the desired aminated product in high yield with low catalyst loading (0.5–2.0 mol%) that are more tolerant to base sensitive functional groups.