Metal- and ligand-centered monoelectronic oxidation of mu-nitrido[((tetraphenylporphyrinato)manganese)(phthalocyaninatoiron)], [(TPP)Mn-N-FePc]. X-ray crystal structure of the Fe(IV)-containing species [(THF)(TPP)Mn-N-FePc(H2O)](I-5)center dot 2THF

摘要

The reaction of mu -nitrod[((tetraphenylporphyrinato)manganese)(phthalocyaninatoiron)], [(TPP)Mn-N-FePc], with I-2 in THF develops with the formation of two different species, i.e., [(THF)(TPP)Mn-N-FePc(H2O)](I-5). 2THF (I) and [(TPP)Mn-IV-N-(FePc)-Pc-III](I-3) (II) On the basis of single-crystal X-ray work and Mossbauer, EPR, Raman, and magnetic susceptibility data, I, found to be isostructural with the corresponding Fe-Fe complex, is shown to contain a low-spin triatomic Mn-IV=N=Fe-IV system (metal-centered oxidation). Data at hand for II Mossbauer, EPR, Raman) show, instead, that oxidation takes place at one of the two macrocycles, very likely TPP (ligand-centered oxidation). The same cationic fragment present in I, and containing the Mn-IV=N=Fe-IV bond system, is also obtained when (TPP)Mn-N-FePc is allowed:to react in THF with (phen)SbCl6 (molar ratio 1:1). There are indications that the use of (phen)SbCl6 in excess (2:1 molar ratio), in benzene, probably determines further oxidation with the formation of a species showing the combined presence of the Mn-IV-Fe-IV couple and of a pi -cation radical. [References: 39]