Iron complexes coordinate profile

The bis(base) (where base = tV-methylimidazole, 1,5-dicyclohexylimidazole, pyridine) complexes of FeII(TpivPP), where TpivPP = tetrakis(o-pivalamidophe-nyl)porphyrin, give characteristic porphyrinate ligand bands.218 Resonance Raman spectra were used to obtain excitation profiles for two a2g ligand modes for a range of iron(II) porphyrins.219 Ligand modes in the resonance Raman spectra of trarax-cross-linked basket-handle iron(II) porphyrins were used to characterise the ruffled, six-coordinated low-spin iron(II) porphyrin complexes.220... 

A typical reaction mechanism is shown in Figure 2.17, where one can see the doubling of the profile due to the HS and LS states. The reaction pathway involves three phases (a) a C-H abstraction phase that leads to an alkyl radical coordinated to the iron-hydroxo complex by a weak OH—C hydrogen bond, labeled as C,. 

The metals discussed in this chapter—lead, arsenic, mercury, and iron—frequently cause significant toxicity in humans. The toxicity profiles of metals differ, but most of their effects appear to result from interaction with sulfhydryl groups of enzymes and regulatory proteins. Chelators are organic compounds with two or more electronegative groups that can form stable covalent-coordinate bonds with cationic metal atoms. As emphasized in this chapter, these stable complexes can often be excreted readily, thus reducing the toxicity of the metal. 

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