Synthesis and magnetic properties of a new hexanuclear iron(III) compound

A hexanuclear Fe(III) compound with new core topology, [Fe6(OMe)2(DHMP)4(AD)2] (1, H3DHMP = (E)-2-((1,3-dihydroxy-2-methylpropan-2-ylimino)methyl)phenol, H2AD = adipic acid), is reported. The hexanuclear Fe(III) core can be viewed as two Fe3(DHMP)2 units connected through double μ2-OMe− bridges, featuring adjacent Fe···Fe distances of 3.105 and 3.109 Å within unit and 3.111 Å between units, respectively. Variable temperature magnetic studies indicate antiferromagnetic exchanges between adjacent Fe(III) ions and which mediated by μ2-OMe− bridges is stronger than those by DHMP alkoxo bridges. Magnetic-structural correlation is also proposed.