Complexes with FeIII2(μ-0)(μ-OH) core surrounded by hydrogen-bonding interaction

Abstract

Three new complexes with FeIII2(μ-0)(μ-OH) core surrounded with one, two, and three amino groups, that is, (6-amino-2-pyridy] methyl)bis(pyridylmethyl)amine (MAPA), bis(6-amino-2-pyridylmethyl) (pyridylmethyl)amine (BAPA), and tris(6-amino-2-pyridylmethyl)amine (TAPA), which act as hydrogen-bonding sites, were synthesized and characterized by electronic absorption spectroscopy and X-ray diffraction analysis. Their structural bond parameters, Fe-N(pyridine), Fe-N(amine), and Fe-μ-O(H) bonds, Fe-Fe distance, and Fe-O-Fe angle, could be explained in terms of a combination of two conflicting interactions between NF2 and μ-O(H) groups, that is, a steric repulsion and a hydrogen-bonding interactions. The LMCT bands of μ-O to iron(III) may be affected by hydrogen-bonding interactions between NH and μ-O(H) groups, which are discussed in connection with the formation processes of compound Q and compound X in sMMO and RNR-R2, respectively. © 2007 The Chemical Society of Japan.