An S = 12 semiquinoid radical-bridged Mn6 wheel complex assembled from an asymmetric redox-active bridging ligand

Abstract

The asymmetric redox-active ligand 4,5-bis(pyridine-2-carboxamido)-1,2-catechol (^N,OLH₄) is prepared and metalated to afford the hexanuclear complex [Mn₆(^N,OL)₆]⁶⁻. Structural analysis and magnetic measurements reveal this complex to feature Mn^II ions bridged by ^N,OL³⁻˙ radicals, which are antiferromagnetically coupled to give an S = 12 ground state.