Facial Tridentate Ligands for Stabilizing Palladium(IV) Complexes

This paper describes the synthesis of a series of Pd-IV complexes containing modular monoanionic tridentate facially coordinated NNN and NNC donor ligands. In all cases, these complexes are stable to reductive elimination for a minimum of several days in solution at room temperature. With appropriately designed tridentate ligands, the Pd-IV adducts participate in both ligand substitution and C-H activation reactions. Overall, this work shows that unsymmetrical fac-L2X type ligands can serve as versatile and tunable scaffolds for modulating the reactivity of octahedral Pd-IV complexes.