| Autor: |
Fokin, A. V., Borisov, Yu. A., Kolomiets, A. F., Raevskii, N. I., Enchev, V. G., Bogachuk, E. B. |
| Zdroj: |
Russian Chemical Bulletin; February 1992, Vol. 41 Issue: 2 p266-271, 6p |
| Abstrakt: |
The heats of formation of polychloroarynes (PCA's) from polychlorobenzenes (PCB's) have been calculated by the AMI method as a function of the composition and structure of the PCB's according to a two-step scheme including deprotonation with the formation of carbanions (PCCA's, ?H1) and dechlorination to PCA's (?H2). The influence of the solvent on ?H1 and ?H2 has been evaluated in the framework of the solvaton model. It has been shown that the value of ?H1 decreases as the number of C1 atoms in the PCB is increased, while ?H2 increases along the same series due to the increase in the relative stability of the PCCA as the number of C1 atoms is increased. Although the dimerization of PCA's with the formation of polychlorobiphenylenes (PCBP's) is forbidden by orbital symmetry rules, calculations of fragments of the potential-energy surface have shown that this reaction takes place with an energy barrier amounting to about 1 kcal/mole. |
| Databáze: |
Supplemental Index |
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