Homoleptic Two-Coordinate Silylamido Complexes of Chromium(I), Manganese(I), and Cobalt(I)

摘要

Anionic two-coordinate complexes of first-row transition-metal(I) centres are rare molecules that are expected to reveal new magnetic properties and reactivity. Recently, we demonstrated that a N(SiMe3)(2)(-) ligand set, which is unable to prevent dimerisation or extraneous ligand coordination at the +2 oxidation state of iron, was nonetheless able to stabilise anionic two-coordinate Fe-I complexes even in the presence of a Lewis base. We now report analogous Cr-I and Co-I complexes with exclusively this amido ligand and the isolation of a [Mn-I{N(SiMe3)(2)}(2)](2)(2-) dimer that features a Mn Mn bond. Additionally, by increasing the steric hindrance of the ligand set, the two-coordinate complex [Mn-I{N(Dipp)(SiMe3)}(2)](-) was isolated (Dipp= 2,6-iPr(2)-C6H3). Characterisation of these compounds by using X-ray crystallography, NMR spectroscopy, and magnetic susceptibility measurements is provided along with ligand-field analysis based on CASSCF/NEVPT2 ab initio calculations.