A series of Pd–PEPPSI complexes were designed and synthesized. The relationship between catalyst structure and properties was systematically investigated. It was revealed that “bulky‐yet‐flexible” C3 bearing ancenaphthyl backbone was a highly efficient precatalyst and could be successfully employed in Suzuki–Miyaura reactions of (hetero)aryl chlorides with (hetero)arylboronic acids at a low palladium loading in the presence of a weak inorganic base in air.

We report herein a highly efficient Pd-catalyzed amination by "bulky-yet-flexible" Pd-PEPPSI-IPent complexes. The relationship between the N-heterocyclic carbenes (NHCs) structure and catalytic properties was discussed. Sterically hindered (hetero)aryl chlorides and a variety of aliphatic and aromatic amines can be applied in this cross-coupling, which smoothly proceeded to provide desired products. The operationally simple protocol highlights the rapid access to C-N bond formation under mild conditions without the exclusion of air and moisture.

A bulky ancenaphthyl skeleton-based α-diimine palladium complex has been developed, which exhibited high reactivity for direct heteroarylation of heteroaryl bromides under aerobic conditions with a broad substrate scope.