112740-05-3Relevant articles and documents
Electrochemical and spectroelectrochemical studies of nickel(II) porphyrins in dimethylformamide
Kadish,Sazou,Liu,Saoiabi,Ferhat,Guilard
, p. 1198 - 1204 (2008/10/08)
The electrochemistry of (P)NiII in DMF is reported where P is the dianion of tetrapyridylporphyrin (TpyP), tetrakis(p-(sodiosulfonato)phenyl)porphyrin (T(p-SO3Na)PP), and tetrakis(p-diethylaminophenyl)porphyrin (T(p-Et2N)PP). Each electrode reaction was monitored by cyclic voltammetry, rotating-disk voltammetry, spectroelectrochemistry, and ESR spectroscopy, and on the basis of these data, an overall oxidation-reduction mechanism for each complex is presented. All three compounds can be reduced by one electron to form π anion radicals or oxidized by one or two electrons to form π cation radicals and dications. Additional oxidations are also associated with the diethylamino groups on (T(p-Et2N)PP)Ni. Reduced (T(p-SO3Na)PP)Ni and (T(p-Et2N)PP)Ni are stable, but (TpyP)Ni undergoes demetalation after reduction by two electrons at the porphyrin π ring system. This is the first example for demetalation of an electroreduced nickel porphyrin and contrasts with results for other nickel porphyrins, which are quite stable after electroreduction. The effect of porphyrin ring structure on the electrochemical behavior of each complex is discussed and compared with that of other related metalloporphyrins.
