Iron(III) Complexes Based on N-Benzylidene-2-Hydroxy-3,5-Di-tert-Butylaniline

摘要

Five-coordinate iron(III) complexes, (ImPh)(2)FeX (X = Cl (I), Br (II), I (III), N-3 (IV)) containing two bidentate Schiff bases (N-benzylidene-2-hydroxy-3,5-di-tert-butylaniline (ImPh)H) and a halogen atom/azide group in the coordination sphere were synthesized and characterized in detail. According to the magnetic susceptibility measurements for polycrystalline samples of I-IV and Mossbauer spectroscopy data in the 2-300 K range, the complexes contain a high-spin metal ion (HS Fe3+, d(5), S-Fe = 5/2). Compounds I-IV are stable in the crystalline state in the absence of oxygen or air moisture; however, in solution, they undergo symmetrization, resulting in the formation of the tris-ligand complex (ImPh)(3)Fe (V), which was also synthesized by the reaction (ImPh)H and FeCl3 (3 : 1). Unlike five-coordinate complexes I-IV, six-coordinate complex V contains low-spin iron(III) ion (LS Fe3+, d(5), S-Fe = 1/2). The molecular structure of I was determined by X-ray diffraction (CIF file CCDC no. 1996527).