| Autor: |
Pirozhenko, V., Boldeskul, I., Kolesnikov, V., Vid, L., Kuz'menko, L. |
| Zdroj: |
Theoretical & Experimental Chemistry; Jul1985, Vol. 21 Issue 4, p388-397, 10p |
| Abstrakt: |
The electronic structure of N-arylthio-1,4-benzoquinone imines (II) was studied by quantum-chemical methods (CNDO/2). It was shown that the special characteristics of the reactivity of the compounds in reaction with chlorine compared with sulfenylketimines RC=N-S-Ar not containing a quinonoid ring may be due to the different nature of the lowest unoccupied molecular Orbitals (LUMO). The UV spectra of compounds (II) were investigated. In the visible region the spectra of all the compounds contain strong absorption (R = R = R = R = R = H, λ = 433 nm, ɛ = 2.12·10 liters/mole·cm), due to intramolecular charge transfer from the sulfur atom to the quinonoid fragment of the molecule. It was established that there is a linear relation between the energy of the transition and the σ constants of the substituents in the aryl fragment. The assignment of the transitions was confirmed by calculations of the UV spectra of N-arylthio-1,4-benzoquinone imines by the PPP method. Comparison of the UV spectra of these compounds with the UV spectra of N-arylsulfonyl-1,4-benzoquinone imines makes it possible to conclude that the sulfur atom of the SO group, unlike the divalent sulfur atom, is not capable of transmitting the electronic effects of the substituents from one part of the molecule to the other. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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