Hard Single-Molecule Magnet Behavior by a Linear Trinuclear Lanthanide–[1]Metallocenophane Complex

A synthetic protocol was developed that involves the transmetalation of a mono-dysprosium–[1]­ferro­cenophane complex with DyX3 (X = Cl– or I–) to afford [Dy3Fc6Li2­(THF)2]−, featuring a rare linear arrangement of magnetically anisotropic Dy3+ ions. The close spatial inter-lanthanide proximity, in combination with μ2-bridging sp2-hybridized CCp groups, enforces significant magnetic coupling and results in hard single-molecule magnet (SMM) behavior, with an effective barrier to magnetization reversal of up to 268 cm–1. Our results highlight the versatility of lanthanide metallo­cenophane architectures toward the development of novel multi­nuclear SMM frameworks.