Facile Access to Dative, Single, and Double Silicon−Metal Bonds Through M−Cl Insertion Reactions of Base‐Stabilized Si II Cations

Silicon(II) cations can offer fascinating reactivity patterns due to their unique electronic structure: a lone pair of electrons, two empty p orbitals and a positive charge combined on a single silicon center. We now report the facile insertion of N‐heterocyclic carbene (NHC)‐stabilized silyliumylidene ions into M−Cl bonds (M=Ru, Rh), forming a series of novel chlorosilylene transition‐metal complexes. Theoretical investigations revealed a reaction mechanism in which the insertion into the M−Cl bond with concomitant 1,2‐migration of a silicon‐bound NHC to the transition metal takes place after formation of an initial silyliumylidene transition‐metal complex. The mechanism could be verified experimentally through characterization of the intermediate complexes. Furthermore, the obtained chlorosilylene complexes can be conveniently utilized as synthons to access Si−M and Si=M bonding motifs bonds through reductive dehalogenation.