Access to Fe Bis(σ-B-H) Aminoborane Complexes through Protonation of a Borohydride Complex and Dehydrogenation of Amine-Boranes.

Herein, we report on the first synthesis and structural characterization of the iron based aminoborane complexes [Fe(PNP)(H)(η :η -H B=NR )] (R=H, Me). These species are formed upon protonation of the borohydride complex [Fe(PNP)(H)(η -BH )] by ammonium salts [NH R ] (R=H, Me). For R=Me, the reaction proceeds via the cationic dinuclear intermediate [{Fe(PNP)(H)} (μ ,η :η -BH )] . A mechanism for the reaction is proposed based on DFT calculations that also indicate the final aminoborane complex as the thermodynamic product. All complexes were characterized by NMR spectroscopy, HRMS, and X-ray crystallography.