Electrochemical Alkene Diazidation via Voltage-Controlled High-Valent Mn Catalysis: A DFT Mechanistic Study.

Electrochemically driven manganese-catalyzed alkene diazidation represents a powerful strategy for C-N bond formation in organic synthesis, in which electrons serve as the sole redox mediator. Despite recent advances, the role of applied potential in directing catalyst speciation and reactivity remains poorly defined. Here, density functional theory (DFT) calculations were employed to map precatalyst speciation and to compute the Gibbs energy profiles of the two C-N bond-forming events. These calculations reveal that alternating anion injection and anodic single-electron oxidation steps dramatically lower the onset potential, enabling access to high-valent Mn(III), Mn(IV), and a formal Mn(V) manifold under mild conditions. Mechanistic analysis reveals that both C-N couplings can proceed via Mn(IV) and Mn(V) pathways, in which the first C-N bond formation is turnover-determining. Different Mn oxidation states exhibit distinct preferences for distal versus proximal C-N coupling. These insights clarify how electrochemical tuning orchestrates high-valent manganese catalysis and furnish a mechanistic blueprint for the rational design of future electrochemical alkene difunctionalization protocols.