A two-coordinate Ni(i) silyl complex: CO2 insertion and oxidatively-induced silyl migrations

The synthesis and reactivity of the first open-shell two-coordinate silyl complex, (IPr) Ni-Si(SiMe3)(3), (IPr = 1,3-di(2,6-di-iso-propyl-henyl) imidazolin-2-ylidene) is reported. Reaction with CO2 results in a novel insertion product that possesses a distorted geometry. Oxidations of the Ni center, with [Cp2Fe][B(C6F5)(4)] and Ph3CCl, result in migratory rearrangements of the silyl ligand, apparently via related silylene intermediates. The distinct oxidation products are interconverted by reactions that introduce or remove chloride.