Cyanide dinuclear iron cyanides

The intermediacy of the species [Fe(CN)5] indicates that this is a 2) [SNlClim)] mechanism. Other substitution reactions of [Fe(CN)5L] anions which also proceed by a D mechanism with generation of the same [Fe(CN)6] " intermediate are discussed in Section 7 of this chapter. Kinetics of dissociation of dinuclear iron(n)-cyanide complexes have been followed by u.v.-visible spectroscopy and by polarography. s Photoaquation of cis- and of trans-[Fe(CNMe)4(CN)a], with irradiation at either charge-transfer or ligand-field frequencies, results in the formation of [Fe(CNMe)2(OHa)a(CN)2] as primary product. ... 

Both CO and cyanide ligands have been identified in the dinuclear active sites of iron-only H-ases that are remarkably organometallic-like and could bind and heterolytically split H2, most likely at an octahedral site trans to the bridging CO (83). 

The catalases catalyze the disproportionation of hydrogen peroxide (equations). Most catalases contain the iron-protoporphyrin IX prosthetic group see Iron Heme Proteins, Peroxidases, Catalases Catalase-peroxidases). However, some bacteria are able to synthesize catalases that are not inhibited even by millimolar concentrations of azide and cyanide, suggesting that some catalases are nonheme enzymes it is now known that these enzymes possess a dinuclear Mn active site. 

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