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

Abstract

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.