A Silylene Stabilized by a σ‐Donating Nickel(0) Fragment

A donor‐stabilized silylene 4 featuring a Ni(0)‐based donating ligand was synthesized. Complex 4 exhibits a pyramidalized and nucleophilic Si(II) center and shows a peculiar behavior due to the cooperative reactivity of Si and Ni centers. Calculations indicate that the orientation of Ni‐ligands with respect to the silylene moiety is crucial in determining the role of the Ni‐fragment (Lewis acid or Lewis base) towards silylene. Indeed, a simple 90° rotation of the Si−Ni bond, reverses the role of Ni, and transforms a classical silylene→Ni(0) complex into an unprecedented Ni(0)→silylene complex.