A two-coordinate manganese(0) complex with an unsupported Mn-Mg bond: Allowing access to low coordinate homo- and heterobimetallic compounds

This study details the synthesis and characterization of an unprecedented two-coordinate, high-spin manganese(0) complex that incorporates an unsupported Mn-Mg bond, viz. L^†MnMg(^MesNacnac) (L ^† = -N(Ar^†)(SiPrⁱ₃), Ar^† = C₆H₂{C(H)Ph₂} ₂Prⁱ-2,6,4; ^MesNacnac = [(MesNCMe) ₂CH]^-; Mes = mesityl). This compound has been utilized as an "inorganic Grignard reagent" in the preparation of the first two-coordinate manganese(I) dimer, L^†MnMnL* (L* = -N(Ar*)(SiMe₃), Ar* = C₆H₂{C(H) Ph₂}₂Me-2,6,4), and the related mixed valence, bis(amido)-hetereobimetallic complex, Mn^II(μ-L^†) (μ-L*)Cr⁰. It is also shown to act as a two-electron reducing agent in reactions with unsaturated substrates.