
%0 Journal Article
%A Dyall, LK 
%A Smith, PAS 
%T Pyrolysis of Aryl Azides.X. Effects of Azide Concentration on Rate Constants and Product Yields
%J Australian Journal of Chemistry
%D 1990/06/01
%V 43
%N 6
%P 997-1007
%K 
%R https://doi.org/10.1071/CH9900997
%U https://www.publish.csiro.au/paper/CH9900997 
%X First-order rate constants (k1) have been measured for pyrolysis of azidobenzenes in decalin solution, in the presence of a free-radical chain inhibitor to prevent any induced decomposition. The new values of k1 for the spontaneous unimolecular  thermolysis are lower than previously reported ones, and require revision of published neighbouring group effects. Product yields ( azo compound and primary amine) vary with initial concentration of azide in ways which suggest the species responsible for induced decomposition is not triplet arylnitrene , but a solvent-derived free radical. There is no evidence for induced decomposition when nitrobenzene is the solvent. For aryl azides with no neighbouring group effects operating in their pyrolysis, the Arrhenius parameters Eact and &#916;Sactobey a precise linear relationship. 
