Issue 11, 1995

Ab initio studies of the thermal decomposition of azaaromatics: free radical versus intramolecular mechanism

Abstract

The energetics of the key reactions in the thermal decomposition of the azaaromatic molecules pyridine, pyrimidine, pyrazine and pyridazine have been investigated using ab initio quantum-chemical techniques. Two distinct mechanisms are considered: (a) intramolecular rearrangement where a bicyclic, Dewar isomer is formed as an intermediate, followed by its fission, producing acetylene and hydrogen cyanide, and (b) the formation of azyl radicals in a CH bond fission initiation reaction followed by decomposition as well as hydrogen abstraction reactions. The calculated energetics of the free radical mechanism are found to be consistent with the results of earlier experimental studies. The estimates of the critical energies associated with the intramolecular Dewar mechanism are, however, such as to rule it out as a viable alternative. A detailed ab initio study of the benzene → Dewar benzene rearrangement is also reported.

Article information

Article type
Paper

J. Chem. Soc., Faraday Trans., 1995,91, 1587-1592

Ab initio studies of the thermal decomposition of azaaromatics: free radical versus intramolecular mechanism

J. Jones, G. B. Bacskay, J. C. Mackie and A. Doughty, J. Chem. Soc., Faraday Trans., 1995, 91, 1587 DOI: 10.1039/FT9959101587

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements