Unmasking the constitution and bonding of the proposed lithium nickelate "LiNiPh(solv)": revealing the hidden CH ligand.

More than four decades ago, a complex identified as the planar homoleptic lithium nickelate "LiNiPh(solv)" was reported by Taube and co-workers. This and subsequent reports involving this complex have lain dormant since; however, the absence of an X-ray diffraction structure leaves questions as to the nature of the Ni-PhLi bonding and the coordination geometry at Ni. By systematically evaluating the reactivity of Ni(COD) with PhLi under different conditions, we have found that this classical molecule is instead a unique octanuclear complex, [{Li(solv)PhNi}(μ-η:η-CH)] (5).