Homoleptic Two‐Coordinate Silylamido Complexes of Chromium(I), Manganese(I), and Cobalt(I). Issue 5 (18th December 2015)

• Record Type: Journal Article
• Authors: Werncke, C. Gunnar; Suturina, Elizaveta; Bunting, Philip C.; Vendier, Laure; Long, Jeffrey R.; Atanasov, Mihail; Neese, Frank; Sabo‐Etienne, Sylviane; Bontemps, Sébastien
• Is Part Of: Chemistry. Volume 22:Issue 5(2016)
• Page Start: 1668
• Page End: 1674
• Publication Date: 2015-12-18
• Subjects: ab initio calculations -- magnetic properties -- N ligands -- transition metals -- coordination modes; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201503980
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: 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‐ i Pr2 ‐C6 H3 ). 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. Abstract : Amido magnetism : The amido N(SiMe3 )2 − ligand is shown to stabilise two‐coordinate metal(I) complexes for Cr and Co, in a manner similar to that previously reported for the Fe analogue (see figure). In the case of Mn, a dimer with an unsupported Mn−Mn bond was isolated. Quantum chemical calculations provided an electronic and magnetic description of the Cr–Co series.