| Autor: |
Mamaev, V. M., Ponamarev, G. V., Zenin, S. V., Evstigneeva, R. P. |
| Zdroj: |
Theoretical and Experimental Chemistry; January 1972, Vol. 6 Issue: 1 p34-39, 6p |
| Abstrakt: |
The McWeeny method [1] for calculating the p-electron currents in aromatic molecules is modified for porphyrins. The distribution of the ring currents of the p-electrons and their contributions to the chemical shifts of NH, ß-H, the meso protons, and the protons of the methyl groups of porphyrins with carbethoxy and methyl substituents in the form of dications and free bases are calculated. We show that the p-electron current in the internal conjugation chain passing through the nitrogen atom decreases during the formation of the dication, while the total ring current increases by almost 10%. Introduction of an electron-accepting substituent in the ß-position intensifies the p-electron current through the C—N bond of the corresponding pyrrole ring, and there is a simultaneous decrease in the total p-electron current. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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