Steric Control in Low-Valent Mn Diamide Complexes: Contrasting Magnesium and Manganese in N₂ and Benzene Activation

Reduction of MnII precursors with bulky diamide ligands provided access to a complex with the longest known Mn-Mn bond and to a rare example of N2 activation at high-spin MnI centres. While some instructive parallels can thus be drawn to observations made for Mg analogues, the accessibility of filled d orbitals in the respective MnI intermediates leads to a distinct behaviour towards benzene that undergoes an oxidative addition.