Nitrosyl complexes of iron

The Fe(II)-NO complexes of porphyrins 66-68) and heme proteins 24, 49, 53, 69-76) have been studied in detail by EPR spectroscopy, which allows facile differentiation between five-coordinate heme—NO and six-coordinate heme—NO(L) centers. However, only a few reports of the Mossbauer spectra of such complexes have been published 68, 77-82), and the only Fe(III)-NO species that have been studied by Mossbauer spectroscopy include the isoelectronic nitroprusside ion, [FeCCNlsCNO)] (7S), the five-coordinate complexes [TPPFe(NO)]+ 68) and [OEPFe(NO)]+ 82), and two reports of the nitro, nitrosyl complexes of iron(III) tetraphenylporphjrrins, where the ligand L is NO2 82, 83). 

S. M. Aldoshin (Director). This session included four presentations. Professor N.P. Konovalova reported on antioxidants and donors of nitrogen monoxide (antitumor effects of nitroxides and NO-donors) the report of N.A. Sanina and S.M. Aldoshin was concerned with a new class of NO-donors (synthesis, structure, properties, and practical use of sulfur-nitrosyl complexes of iron). Free-radical mechanisms of induction and development of secondary necrosis after gun wounds were the subject of the lecture by G.N. Bogdanov L.D. Smirnov reported on pharmacological properties and promising clinical application of antioxidants of the heteroaromatic array. 

Nitrosyl Complexes of Iron-Sulfur Clusters Anthony R. Butler, Christopher Glidewell, and Min-Hsin Li... 

Dinuclear and tetranuclear complexes are also suitable starting materials, and much of the synthetic and substitutional chemistry of these species reflects the ability of the systems to sustain monomeric solvated dinitrosyl species such as [Fe(NO)2(solvent)2]+ or [Fe(NO)2(SR)(solvent)]. The latter tend to be formed in solvents having poor and the former in ones having good tt-acceptor capabilities. A review of nitrosyl complexes of iron-sulfur complexes is available. 

The NO+ ion is isoelectronic with CO, and, like CO, will form bonds to metals. Thus, for example, analogous to nickel carbonyl, Ni(CO)4, there is the isoelectronic Co(CO)3NO. These transition-metal nitrosyl complexes are discussed in Section 22-12, but we may note here that the compound responsible for the brown ring in the test for nitrates is a nitrosyl complex of iron with the formula [Fe(H20)5N0]2 +. ... 

Both the chloroiron and phenyliron octaalkylcorrolates can be oxidized electrochemically by two or three one-electron processes, and reduced by two one-electron processes.One-electron reduction of each produces the simple [XFe Corr], while one-electron oxidation of each produces the [XPe Corr -J+jr-cation radicals. The nitrosyl complex of iron (III) octaethylcorrolate has been formed and both it and its 1-electron oxidized product have been characterized structurally and electrochemically. 

Butler AR, Glidewell C, Li MH (1988) Nitrosyl complexes of iron-sulfur clusters. In Sykes AG (ed) Advances in uunganic chemistry, vol 32. Academic, London... 

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