Flash Communication: Ring-Opening of Biphenylene with Magnesium(I) and Magnesium–Dinitrogen Complexes

Rare examples of reductive C–C single bond cleavages using main group metal complexes have been achieved in reactions between biphenylene and a magnesium–dinitrogen complex and an anionic magnesium­(I) compound, [K2{Mg­(EtNONTCHP)}2(μ-N2)] and [K­{Mg­(EtNONTrip)}]2 (EtNONTCHP and EtNONTrip = bulky bis­(anilido)­xanthenes), respectively. In the products, [K2{Mg­(EtNONAr)}2(μ-C12H8)] (Ar = TCHP or Trip), the reduced biphenyldiyl ligand [C12H8]2–, bridges two Mg centers through its 2,2′-positions.