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, [K 2 {Mg( Et NON TCHP )} 2 (μ-N 2 )] and [K{Mg( Et NON Trip )}] 2 ( Et NON TCHP and Et NON Trip = bulky bis(anilido)xanthenes), respectively. In the products, [K 2 {Mg( Et NON Ar )} 2 (μ-C 12 H 8 )] (Ar = TCHP or Trip), the reduced biphenyldiyl ligand [C 12 H 8 ] 2–, bridges two Mg centers through its 2,2′-positions.