Synthesis, structures, and magnetic behavior of two high-spin binuclear Fe(III) complexes
摘要:
The reaction of 2-t-butyl-4-ethylphenol, formaldehyde, and 2-amino propanol or 3-amino-1- propanol at 2 : 2 : 1 provides N-(1-ethanol)-N,N-bis(3-t-butyl-5-ethyl-2-hydroxybenxyl)amine (H(3)L') and N-(3-amino-1-propanol)-N, N-bis(3-t-butyl-5-ethyl-2-hydroxybenxyl) amine (H(3)L ''), respectively. In the presence of Et(3)N, the reaction of FeCl(3)center dot 6H(2)O and H(3)L' or H(3)L '' gives dinuclear Fe(III) complexes [Fe(2)L'(2)] 1 and [Fe(2)L ''(2)] 2, respectively, which have been characterized by X-ray crystallography, magnetic measurements, and cyclic voltammetry (CV). Magnetic studies indicate significant antiferromagnetic coupling between the iron(III) centers for 1 and 2. The values obtained for the coupling constants (J) are -12.35 cm(-1) for 1 and -16.26 cm(-1) for 2. CVs of 1 and 2 reveal one reversible wave at -0.80 and -0.82V versus AgCl/Ag, respectively, which can be ascribed to redox coupling of Fe(III)Fe(II)/Fe(III)Fe(III).