Hydrazine Capture and N–N Bond Cleavage at Iron Enabled by Flexible Appended Lewis Acids

Incorporation of two 9-borabicyclo[3.3.1]­nonyl substituents within the secondary coordination sphere of a pincer-based Fe­(II) complex provides Lewis acidic sites capable of binding 1 or 2 equiv of N2H4. Reduction of the 1:1 Fe:N2H4 species affords a rare Fe­(NH2)2 complex in which the amido ligands are stabilized through interactions with the appended boranes. The NH2 units can be released as NH3 upon protonation and exchanged with exogenous N2H4.