Terminal Imido Complexes of the Groups 9–11: Electronic Structure and Developments in the Last Decade

Abstract

We thank the Fonds der Chemischen Industrie (Liebig fellowship for D.M.), the German‐American Fulbright Commission (Fulbright‐Cottrell Award for D.M.) as well as the Bavarian Equal Opportunities Sponsorship – Realization of Equal Opportunities for Women in Research and Teaching (fellowship for A.G.) for financial support. We thank the RRZ Erlangen for computational resources.

On the Synthesis of a T‐Shaped Imido Nickel Complex and Trigonal Amido Nickel Complexes

“…The group of Betley reported a bond length of 1.696(2) Å for an arylimido complex showing imidyl like character [16] . The N1−C1 bond in [ 1 ] − amounts to 1.359(4) Å, that is at the upper end of known aryl imido nickel complexes, making a imidyl like bonding situation however unlikely [16,19,26,28,32,35] . The geometry around nickel is best described as T‐shaped with the newly formed −N(Ph)SiMe 3 ligand in the equatorial position.…”

“…[11][12][13][14][15][16][17] Thereby it shows that more intriguing bonding situations in such imido metal complexes, that deviates from the classic description as an [NR] 2À unit bound to a M n + 2 ion, are increasingly found. [18,19] These encompass for iron, [11] cobalt [20,21] and nickel [16,22,23] very few examples of complexes with a metal bound imidyl [NR] À unit as well as an isolated and putative copper(I) nitrene species. [24] Taking a closer look at nickel, only a small number of isolable, structurally identified imido nickel complexes are known, all in a low-coordinate environment (coordination number � 3).…”

“…As such the amount of the more reactive complexes in higher spin‐states is still limited [11–17] . Thereby it shows that more intriguing bonding situations in such imido metal complexes, that deviates from the classic description as an [NR] 2− unit bound to a M n+2 ion, are increasingly found [18,19] . These encompass for iron, [11] cobalt [20,21] and nickel [16,22,23] very few examples of complexes with a metal bound imidyl [NR] − unit as well as an isolated and putative copper(I) nitrene species [24] …”

“…The related high‐spin arylimido cobalt complex [Co(NDipp)L 2 ] (L=−N(Dipp)SiMe 3 , Dipp=2,6‐di iso propylphenyl) exhibited radical imidyl character of the imide ligand, whereas steric protection was needed to allow for its isolation [36] . We were thus curious if these findings would translate to the heavier neighbor nickel, where a more covalent, thus more reactive metal‐imide bond might be expected [18,19] …”

A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N–O Reagent as the “Amino” Source and “Oxidant”

“… 80 , 86 , 90 Thus, many aspects of nitrogen transfer reactions need to be explored, which likely will unveil a rich and distinctive chemistry compared to the oxygenation/hydroxylation chemistry. 91 , 92 Inspired by the rich utility of amination chemistry across various fields of chemical synthesis and catalysis, as well as the intriguing spectroscopic and electronic structure that can be expected for the proposed iron–nitrogen intermediates, we sought to explore the role of iron and the mechanistic details in the catalytic amination reaction using a wide range of spectroscopic methods, as well as computational studies.…”