Kinetics of the thermal decomposition of trans ‐1,2‐dicyanocyclobutane

The kinetics of the thermal decomposition of trans ‐1,2‐dicyanocyclobutane, which yields only vinyl cyanide, have been studied in the temperature range of 570°‐660°K using a stirred‐flow reactor. The reaction was found to be first order and homogeneous with rate constants represented by the Arrhenius equation\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm log}k{\rm (sec}^{- 1} {\rm) =}{{{\rm (16}{\rm .0} \pm {\rm 0}{\rm .3)} - {\rm (52}{\rm .9} \pm {\rm 0}{\rm .8)}} \mathord{\left/ {\vphantom {{{\rm (16}{\rm .0} \pm {\rm 0}{\rm .3)} - {\rm (52}{\rm .9} \pm {\rm 0}{\rm .8)}} \theta}} \right. \kern-\nulldelimiterspace} \theta} $$\end{document} where θ = 2.303 RT kcal/mol. The Arrhenius parameters are considerably higher than previously reported. On the assumption of a biradical mechanism the results are consistent with a cyano stabilization energy of ∼5 kcal/mol, in good agreement with the results of recent studies of related systems.