Dinitrogen Splitting Coupled to Protonation

Abstract

Abstract The coupling of electron‐ and proton‐transfer steps provides a general concept to control the driving force of redox reactions. N 2 splitting of a molybdenum dinitrogen complex into nitrides coupled to a reaction with Brønsted acid is reported. Remarkably, our spectroscopic, kinetic, and computational mechanistic analysis attributes N−N bond cleavage to protonation in the periphery of an amide pincer ligands rather than the {Mo−N 2 −Mo} core. The strong effect on electronic structure and ultimately the thermochemistry and kinetic barrier of N−N bond cleavage is an unusual case of a proton‐coupled metal‐to‐ligand charge transfer process, highlighting the use of proton‐responsive ligands for nitrogen fixation.