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Updated: Aug 14, 2026

Measurement of Tissue Non-Heme Iron Content using a Bathophenanthroline-Based Colorimetric Assay
Published on: January 31, 2022
Diiron(II) mu-aqua-mu-hydroxo model for non-heme iron sites in proteins
Ivan V Korendovych1, Sergey V Kryatov, William M Reiff
1Department of Chemistry, Tufts University, Medford, Massachusetts 02155, USA.
Abstract:
We have synthesized a diiron(II) complex with a novel aqua-hydroxo bridging motif, [Fe2(mu-H2O)(mu-OH)(TPA)2](OTf)3 (1). This is a new member of the diiron diamond core family. The complex is stable in solution in nonpolar solvents as well as in the solid state. Two high-spin iron(II) sites are antiferromagnetically coupled (J = -9.6 cm(-1)). The drastic difference of ca. 1 V in the redox potential between complex 1 and its bis(hydroxo)-bridged analogue Fe2(OH)2(TPA)3+ is accompanied by only a moderate difference in the dioxygen reactivity. This observation is consistent with the inner-sphere mechanism of iron(II)-dioxygen association rather than the outer-sphere electron transfer.
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