Dimeric iron(III) complexes with salicylaldimine ligands: structures, magnetic properties, and activity of H2O2 disproportionation

[[abstract]]The preparations, characterizations, structures, magnetic properties and catalase-like activities of four new alkoxy bridged dimeric five-coordinate iron(III) salicylaldimine complexes, [FeL1Cl]2 (1) (H2L1=N-(3-hydroxypropyl)(5-bromosalicylaldimine)), [FeL2Cl]2 (2) (H2L2=N-(3-hydroxypropyl)(3-methoxysalicylaldimine)), [FeL3Cl]2 (3) (H2L3=N-(3-hydroxypropyl)(4-diethylaminosalicylaldimine)), and [FeL4Cl]2 (4) (H2L4=N-(3-hydroxypropyl)(3,5-diiodosalicyaldimine)) are reported. The crystal structure of complexes 1–3 show an alkoxy bridged dimeric iron(III) complex, which occupies a site of inversion symmetry, and each iron atom is five-coordinate with square-pyramidal arrangements. Mössbauer spectra reveal the presence of high-spin iron(III) ions in complexes 1–4. The magnetic susceptibility (300–2 K) indicate an antiferromagnetic interaction between the two oxygen-bridged iron(III) ions with J=−17.5, −12.40, −19.0 and −21.0 cm−1 for the complexes of 1–4, respectively. The H2O2 disproportionation of complexes 1–4 in acetonitrile at 25°C show the rate law of kobs[H2O2]2[complex].[[notice]]補正完畢[[journaltype]]國