Description:
<jats:title>Abstract</jats:title><jats:p>The article reviews results of research that was initially aiming at complexes containing new and unusual [M—N—E] element combinations (M = transition metal, E = main group element), but soon turned into studies on model complexes for metal enzymes such as nitrogenases, hydrogenases or CO dehydrogenases, because several of the resulting [M—N—E] complexes exhibited reactions relevant to these enzymes. It could be shown that alkylation of transition metal thiolate nitride complexes gives alkylimido complexes when bulky and mild alkylation reagents, e.g. Ph<jats:sub>3</jats:sub>C<jats:sup>+</jats:sup>, are used. Hydride addition to [Ru(NO)(py<jats:sup>bu</jats:sup>S<jats:sub>4</jats:sub>)]<jats:sup>+</jats:sup> yielded [Ru(HNO)(py<jats:sup>bu</jats:sup>S<jats:sub>4</jats:sub>)], which contains a bifurcated [M—N(X, Y)] bridge. The diazene complex [μ‐N<jats:sub>2</jats:sub>H<jats:sub>2</jats:sub>{Ru(PCy<jats:sub>3</jats:sub>)(S<jats:sub>4</jats:sub>)}<jats:sub>2</jats:sub>] undergoes H<jats:sup>+</jats:sup>/D<jats:sup>+</jats:sup> and H<jats:sup>+</jats:sup>/D<jats:sub>2</jats:sub> exchange reactions that enabled to rationalize the until then inexplicable ‘N<jats:sub>2</jats:sub> dependent HD formation’ catalyzed by nitrogenases. Out of a larger number of [Ni(NE)(S<jats:sub>3</jats:sub>)] complexes, the compound [Ni(NHPPr<jats:sub>3</jats:sub>)(S<jats:sub>3</jats:sub>)] proved capable to model structure <jats:italic>and</jats:italic> reactivity features of [NiFe] hydrogenases. The [Ni(L)(S<jats:sub>3</jats:sub>)] complexes with L = N<jats:sub>3</jats:sub><jats:sup>—</jats:sup> and N(SiMe<jats:sub>3</jats:sub>)<jats:sub>2</jats:sub><jats:sup>—</jats:sup> exhibit extremely high reactivity towards CO, CO<jats:sub>2</jats:sub> and SO<jats:sub>2</jats:sub>. The reactions lead to NCO<jats:sup>—</jats:sup>, CN<jats:sup>—</jats:sup> and NSO<jats:sup>—</jats:sup> complexes and bear potential relevance for carbon monoxide dehydrogenase reactions.</jats:p>