Reversible Insertion of a CC Bond into Magnesium(I) Dimers: Generation of Highly Active 1,2-Dimagnesioethane Compounds

The insertion of 1,1-diphenylethylene into the Mg–Mg bond of two magnesium­(I) dimers, [(^ArNacnac)­Mg−]₂ (Ar = C₆H₂Me₃-2,4,6 (Mes); C₆H₃Et₂-2,6 (Dep)), yielding 1,2-dimagnesio­ethane products, [{(^ArNacnac)­Mg}₂­(μ‑CH₂CPh₂)], is described. These reactions are readily reversible at room temperature and thus represent the first examples of room-temperature reversible redox processes for s-block metal complexes. The 1,2-dimagnesio­ethane products are highly activated magnesium alkyls and show unprecedented, uncatalyzed reactivity toward H₂, CO, and ethylene. Computational studies have investigated the mechanisms of all presented reaction types