Reactions Involving Metals in Porphyrins and Related Ring Systems

4 Reactions involving Metals in Porphyrins and Related Ring Systems 

Antonini and M. Brunori, Hemoglobin and Myoglobin in the Reactions with Ligands , North-Holland, Amsterdam, 1971. 

Schmelzer, R. Steiner, A. Mayer, T. Nedetzka, and H. Fasold, European . Biochem., 1972, 25, 491. 

Solvent exchange rates have been measured, by n.m.r. spectroscopy, for two further high-spin iron(m) porphyrins and a manganese(m) porphyrin 

The frequent presence of an imidazole-co-ordinated residue in an axial position, coupled with the suggestions that metal-imidazole bond rupture might play an important role in biological processes of coenzyme B12 and the cytochrome c system, indicates that a detailed characterization of the structure and dynamics of the imidazole-metal bond in such porphyrin complexes could have significant biological implications. La Mar and Walker present some preliminary data on the exchange of iV-methylimidazole (WMIm) on the bis-adduct of A MIm with [Fe(tpp)Cl] in CDCI3, and Kolski and Plane describe temperature-jump studies on the reaction between imidazole and the iron(m) derivative of ethylenediamine-substituted protoporphyrin IX in water. 

---