The synthesis and characterization of Fe-diphosphineborane complexes are described in the context of N2 functionalization chemistry. Iron aminoimides can be generated at room temperature under 1 atm N2 and are shown to react with E-H bonds from PhSiH3 and H2. The resulting products derive from delivery of the E fragment to Nα and the H atom to B. The flexibility and lability of the Fe-BPh interactions in these complexes engender this reactivity.