F. Walker, H. Nasri, I. Turowska-Tyrk
Dec 4, 1996
Citations
0
Influential Citations
65
Citations
Journal
Journal of the American Chemical Society
Abstract
The synthesis and characterization of isocyanide complexes of (porphyrinato)iron(III) species, [(Porph)Fe(t-BuNC)2]ClO4, Porph = OEP, TPP, are reported. The crystal structures of [(TPP)Fe(t-BuNC)2]ClO4 and [(OEP)Fe(t-BuNC)2]ClO4 have been determined. Consistent with the expected effect from the strong π-acceptor character of the axial tert-butyl isocyanide ligands, the X-ray structure of the complex shows that the porphyrinate ring is strongly ruffled. The spectroscopic properties of these complexes suggest the possibility of “blurring” of the definitions of the electron configurations of low-spin Fe(III) macrocycles having (dxy)1 electronic ground states, with the extreme possibilities being low-spin Fe(III)-(macrocycle)2-, with the unpaired electron localized in the dxy orbital of the metal, and low-spin Fe(II)-(macrocycle)1-•, with the unpaired electron localized on the macrocycle. EPR spectroscopy of the TPP and OEP complexes shows that the g-values (g⊥ = 2.20−2.28, g∥ = 1.94−1.83) are consistent with...