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Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Self-assembly of a trigonal bipyramidal architecture with stabilisation of iron in three spin states
Lauren L K Taylor1, Iñigo J Vitorica-Yrezabal1, Ivana Borilović1,2
1Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK. imogen.riddell@manchester.ac.uk.
Abstract:
Self-assembly and characterisation of a supramolecular trigonal bipyramidal iron cage containing an [FeIII(μ2-F)6(FeII)3]3+ star motif at its core is reported. The complex can be formed in a one step reaction using an heterotopic ligand that supports site-specific incorporation of iron in three distinct electronic configurations: low-spin FeII, high-spin FeII and high-spin FeIII, with iron(II) tetrafluoroborate as the source of the bridging fluorides. Formation of a μ2-F bridged mixed-valence FeII-FeIII star is unprecedented. The peripheral high-spin FeII centres of the mixed-valence tetranuclear star incorporated in the iron cage are highly anisotropic and engage in F-mediated antiferromagnetic exchange with the central FeIII ion.
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