Linear open-shell 3d-metal silylamides - a versatile tool in coordination chemistry

Linear 3d-metal complexes with open-shell metal ions have fascinated coordination chemists for decades. Originally the focus was on metal(II) species, yet the synthetic possibilities to acquire their reduced analogues, together with the introduction of NHCs as stabilizing co-ligands, have expanded the structural knowledge and feasible oxidation states to +I and even 0. Despite a certain wealth of structural data, insights into the reactivity or even catalytic applications of such compounds remained comparably thin for a long time given the intrinsic lability of these coordinatively and electronically unsaturated compounds. In this feature article we review the emerging chemistry and reactivity of silylamide based species, as mostly for these a comprehensive, broader picture of their reactivity patterns has been developed in recent years. Together with related, selected reactivity examples of other linear metal complexes, this review will serve as an entry point for interested molecular organic/inorganic chemists to join the scientific endeavours within this field.