PUB - Publikationen an der Universität Bielefeld

The reaction of 4-tert-butyl- 2,6-bis(hydroxymethyl) phenol (H3L) with Fe-III. ions in methanol in the presence of an excess of NaOH afforded the tetra-anionic dinuclear complex Na-4[(HL)(4)Fe-2(III)(CO3)].11MeOH.3H(2)O (1). Changing the solvent to an ethanol/dme (dme = 1,2-dimethoxyethane) mixture led to the formation of the decanuclear complex [(HL)(12)Fe-III Na-10(4)(mu(4)-O)(4)(mu(3)-OH)(2)(dme)(2)(EtOH)(2)].2dme.8EtOH (2). The Mossbauer spectra of 1' and 2 at 80 K are consistent with high spin Fe-III sites in distorted octahedral O-6 coordination environments. Compound 1 consists of a tetra-anionic dinuclear iron complex with the unprecedented [Fe-III(mu(2)-OBz)(2)(mu(2)-CO3)Fe-III](2+) core. Compound 2 contains a core of hydrous ferric oxide produced by a modified hydrolysis of Fell, ions in the presence of the ligand. Eight benzyl alcohol groups are located on the surface of 2 leading to a 2D network structure by intermolecular hydrogen bonding. The temperature dependence of the magnetic susceptibilities of 1' and 2 indicates antiferromagnetic interactions between the ferric ions. The data for V were fitted with J = -4.4 cm(-1) and g = 1.98, H = -2JS(1)S(2). (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.