Formation and ^1H NMR Spectra of Low Spin Ferric Porphyrin Radical Cations with Orientationally Fixed Imidazole Ligands
Chemical oxidation of tetradurylporphyrinatoiron(III) chloride followed by the addition of 2-methylimidazole at −78 °C gave the first example of the low spin ferric porphyrin radical cation with orienta ionally fixed imidazole ligands, [Fe(TDP<SUP>•</SUP>)(2-MeIm)<SUB>2</SUB>]<SUP>2+</SUP>. The degree of asymmetric spin distribution on the pyrrole β carbons in the radical cation was estimated to be close to that in the starting low spin complex, [Fe(TDP)(2-MeIm)<SUB>2</SUB>]<SUP>+</SUP>, which was ascribed to the orthogonality of porphyrin a<SUB>2u</SUB> with imidazole π orbitals.
- Chemistry letters
Chemistry letters 1996(9), 805-806, 1996-09
The Chemical Society of Japan