Photochemically Induced Reductive Elimination as a Route to a Zirconocene Complex with a Strongly Activated N2 Ligand

The zirconocene dinitrogen complex {(η⁵‐C₅Me₄H)₂Zr}₂(μ₂,η²,η²‐N₂)] was synthesized by photochemical reductive elimination from the corresponding zirconium bis(aryl) or aryl hydride complexes, providing a high‐yielding, alkali metal‐free route to strongly activated early‐metal N₂ complexes. Mechanistic studies support the intermediacy of zirconocene arene complexes that in the absence of sufficient dinitrogen promote C? H activation or undergo comproportion to formally Zr^III complexes. When N₂ is in excess arene displacement gives rise to strong dinitrogen activation.