Application of the Mössbauer spectroscopy to the study of the oxidation state of azaferrocene derivatives

Abstract

Azaferrocene has two active sites of iron and nitrogen atoms. Drastic change of the oxidation state in iodine oxidation of azaferrocene is observed by introducing the methyl substituents into the pyrrole ring, while all the N-methylates show a similar electronic state. It was revealed that an introduction of methyl substituent to the pyrrole ring promotes the oxidation of nitrogen atom in pyrrole ring more than the central iron atom.

Synthesis and Reactivity of Sterically Encumbered Diazaferrocenes

“…Therefore, alkyl substitution at the sensitive 2,5-positions significantly increases the stability of the (di)­azaferrocenium cations. Several electrochemical studies on the oxidation of azaferrocenes have been reported. ,, Furthermore, Nakashima and co-workers accomplished the chemical oxidation of azaferrocene, 2,5-dimethylazaferrocene, and 2,4-dimethylazaferrocene with I 2 and characterized these species by several spectroscopic techniques, but no structural information is available on these complexes …”

“…11b,e,26c Furthermore, Nakashima and co-workers accomplished the chemical oxidation of azaferrocene, 2,5-dimethylazaferrocene, and 2,4-dimethylazafer- rocene with I 2 and characterized these species by several spectroscopic techniques, but no structural information is available on these complexes. 27 Single crystals of [5-Fe][SbF 6 ] were grown by slow pentane diffusion into a CH 2 Cl 2 solution, and the molecular structure is shown in Figure 4. Selected bond distances and angles are given in Table 2.…”