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Six-Coordinate Nitrato Complexes of Iron Porphyrins with Trans S-Donor Ligands
Tigran S Kurtikyan1, Gurgen M Gulyan1, Hayk S Minasyan1
1Molecule Structure Research Centre of the Scientific and Technological Centre of Organic and Pharmaceutical Chemistry , National Academy of Sciences of the Republic of Armenia , 0014 , Yerevan , Armenia.
Abstract:
The reaction of dimethyl sulfide (DMS) and tetrahydrothiophene (THT) with thin, amorphous layers of the nitrato complexes Fe(Por)(η2-O2NO) (Por = meso-tetraphenylporphyrinato dianion or meso-tetra- p-tolylporphyrinato dianion) at low temperature leads to formation of the corresponding six-coordinate complexes Fe(Por)(L)(η1-ONO2) (L = DMS, THT) as characterized by Fourier transform infrared and optical spectroscopy measurements. Adduct formation was accompanied by bidentate-to-monodentate linkage isomerization of the nitrato ligand, with the FeIII center remaining in a high-spin electronic state. These adducts are thermally unstable; warming to room temperature restores the initial Fe(Por)(η2-O2NO) species.
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