H2 activation by zirconaziridinium ions: σ-bond metathesis versus frustrated Lewis pair reactivity

Abstract

Zirconaziridinium ions [Cp₂Zr(η²-CH₂NR₂)]⁺ can potentially activate H₂ by two routes: σ-bond metathesis or FLP reactivity. We show here that Zr–C hydrogenolysis by σ-bond metathesis precedes and enables subsequent heterolytic H₂ cleavage through FLP pathways. DFT calculations show the involvement of transition states with approximately linear N⋯H⋯H and bent Zr⋯H⋯H arrangements without any direct Zr–amine interaction.