| Autor: |
Fokin, A., Borisov, Yu., Raevskii, N., Kolomiets, A. |
| Zdroj: |
Bulletin of The Russian Academy of Sciences, Division of Chemical Science; 1992, Vol. 41 Issue 8, p1346-1350, 5p |
| Abstrakt: |
The AM1 method was used to calculate the enthalpies of formation of polychlorinated 1,2-ketocarbenes (PCKC) from polychlorophenols (PCP) according to a two-step scheme - deprotonation with the formation of polychlorophenolate anions (PCPA, ΔH) and dechlorination to PCKC (ΔH). It was shown that the biradical state of PCKC has a lower energy than the singlet state. The influence of the solvent on ΔH and ΔH was estimated within the framework of the solvation model. It was shown that ΔH decreases with increasing number of Cl atoms in PCP, which is evidence of an increase in the acidity, whereas ΔH increases, which is due to an increase in the relative stability of PCPA with increasing number of Cl atoms. A calculation of the dimerization of PCKC in the singlet state showed that this process occurs with virtually no activation energy. The electronic state of 1,2-ketocarbene and its analogs in the singlet state was studied by a nonempirical MO LCAO SCF method. A comparison with 1,2-thioketocarbene and its analogs was performed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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