Iron-Mediated Si–H Bond Activation: Synthesis, Characterization and Spectral Properties of a Series of Fe II (H)(SiR ₃ )(dmpe) ₂ Complexes

Synthesis and structural characterization of a series of iron(II) silyl hydrides stabilized by a bisphosphine ligand are discussed. Fe II (H)(SiR 3 )(dmpe) 2 compounds were formed by insertion of in situ generated Fe 0 (dmpe) 2 in the presence of Si–H partners (R 3 SiH = PhSiH 3, Ph 2 SiH 2, and Ph 3 SiH). Multinuclear NMR monitoring ( 1 H, 31 P, 29 Si) demonstrated a strong preference for the cis configuration regardless of the silicon substituents, a tendency mirrored by DFT calculations, which originates from the strong trans influence of the silyl ligands, making those compounds rather unusual in the family of octahedral ferrous hydrides. Stoichiometric reactivity of the compounds toward organic electrophiles and proton sources were investigated.