Synthesis and Reactivity of Stable Alkyl-Pd(IV) Complexes Relevant to Monodentate N‑Directed C(sp3)–H Functionalization Processes

Alkyl-Pd­(IV) complexes are frequently invoked in the proposed mechanisms of Pd-catalyzed C­(sp3)–H functionalization reactions, though few examples of Pd­(IV) complexes containing cyclo­palladated substrates have been isolated due to the instability of the high-valent Pd­(IV) center. Herein, we report the synthesis of stable and isolable OCO pincer-supported alkyl-Pd­(IV) complexes containing cyclo­palladated alkyl­amine and oxime frameworks, which represent the first examples of alkyl-Pd­(IV) complexes derived from the oxidation of cyclo­palladated monodentate N-donor substrates. The aminoalkyl-Pd­(IV) complexes reacted efficiently with O- and N-nucleophiles to afford γ-functionalized alkyl­amine products. A mechanistic study of the nucleophile-mediated reductive elimination was conducted using an oxime-derived Pd­(IV) complex, which revealed the intermediacy of a previously unexplored anionic Pd­(IV) species.