| Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1996: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1995: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Research Abstract |
We have observed that the electon configuration of iron in ferric porphyrin complexes changes from the usual (dxy)^2(dxz, dyz)^3 to unusual (dxz, dyz)^4(dxy)^1 as the deformation of the porphyrin ring increases in the following two systems.
A series of bis (imidazole) (meso-tetraalkylporphyrinatoiron (III)) complexes, where R=Me, Et, and iPr, have been prepared. The crystallographic analysis of the ethyl complex has revealed that the porphyrin ring is highly S_4 ruffled. While the ^1H NMR signal of the pyrrole protons in the unsubstituted complex appears at a normal high field region as a low spin complex, those of the alkyl substituted complexes are observed at rather low field. Particularly in the isopropyl complex, the pyrrole signals appear at so called "diamagnetic region". Furthermore, the EPR of the isopropyl complex shows unusual "axial type" spectra. Based on these results, we concluded that the electronic configuration of iron in these complexes changes from the usual (dxy)^2(dxz, dyz)^3 to the unusual (dxz, dyz)^4(dxy)^1 as the nonplanarity of the porphyrin ring increases.
A series of bis (cyanide) (meso-tetraalkylporphyrinatoiron(III)) complexes, where R=H,Me, Et, and iPr, have been prepared and examined by ^1H NMR,^<13>C NMR,and EPR spectra. While the unsubstituted complex (R=H) showed spectropic results similar to those of the typical low spin complexes, the alkyl substituted complexes exhibited quite different results ; pyrrole 1H and cyanide ^<13>C signals showed rather small paramagnetic shifts. Corresponding to the NMR results, the EPR of the alkyl substituted complexes gave the unusual "axial type" spectra instead of the usual "large gmax type" spectra. Based on these results, we concluded that the electronic configuration of iron in these complexes changes from (dxy)^2(dxz, dyz)^3 to (dxz, dyz)^4(dxy)^1 as the nonplanarity of the porphyrin ring increases.
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