Glutarohydrazide-based tetra‑iron(III) complex featuring zigzag-like arrangement

Herein, using a flexible glutarohydrazide ligand (L1), we assemble a new tetrairon(III) compound; [Fe 4 (L1) 2 (μ 3 -O) 2 (μ 2 -CH 3 O) 2 (Cl) 2 ]·CH 3 OH ( 1 ), featuring a zigzag-like arrangement of the metal centers. Structurally, the two chelating ligands were arranged in an inverted U-shaped conformation. Moreover, while the chloride act as a terminal capping ligand, both oxo (μ 3 -O 2− ) and methoxo (μ 2 -CH 3 O − ) involve as bridging motifs create a planar zigzag-like arrangement. Both calculated continuous shape measurement (CShM) and bond valences sum (BVS) values revealed that each metal center was found to be under distorted octahedral geometry and + 3 oxidation state, respectively. Magnetic investigations revealed that compound 1 exhibited a temperature-dependent χ M T value of 6.56 cm 3 mol −1 K at 300 K found to be well below the expected value of 17.5 cm 3 mol −1 K for four non-interacting iron S = 5/2 ions. This could be due to the super-exchange coupling mediated by the non-magnetic anionic bridging ligands (oxo and methoxo) that could involve as super-exchange centers promoting super-exchange mediated anti-ferromagnetic interactions. We report a new Fe(III) compound realized via flexible glutarohydazide ligand featuring zigzag-like tetra-nuclear array exhibiting a super-exchange mediated anti-ferromagnetic interactions. • A new tetrairon(III) compound has been described. • Stucturally, a planar four metal centers featuring a zigzag-like arrangement was obtained. • BVS values revealed that each metal center is under +3 oxidation state. • Magnetic measurment showed super-exchange mediated anti-ferromagnetic interactions.