Mono- and binuclear complexes of iron(III) with 1,2-bis(2-hydroxybenzamido)ethane

摘要

Complexes of the type [(Fe(L))(2)O] . H2O (H2L = 1,2-bis(2-hydroxybenzamido)ethane), [(Fe(L))(2)ter] . 5H(2)O H(2)ter = terephthalic acid), [Fe(L)bpy]BPh4 (bpy = 2,2'-bipyridyl), and [Fe(L)phen]ClO4 . H2O (phen = o-phenanthroline) were prepared and studied by elemental analysis, magnetochemical measurements, and spectroscopic methods. [(Fe(L))(2)O] . H2O and [(Fe(L))(2)ter] . 5H(2)O are probably binuclear, and the weak antiferromagnetic exchange interaction, (mu(eff) per one atom of iron(III) was found to be 3.59 BM/77 K-4.91 BM/290 K (J = -7 cm(-1), H= -2JS(1)S(2), S-1 = S-2 = 5/2) for the mu-oxo complex and 4.21 BM/82 K-5.35 BM/297 K (J = -5 cm(-1)) for the mu-terephthalato complex. The iron(III) complexes with bpy or phen are probably mononuclear; their anomalous mu(eff) values (3.51 BM/80 K-3.68 BM/297 K for (Fe(L)bpy]BPh4 and 4.93 BM/259 K for [Fe(L)phen]ClO4 . H2O, respectively) agree neither with high spin (5.7-6.1 BM) nor with low spin (2.1-2.5 BM) configurations. [References: 13]