The pyrolysis of 2‐nitrosoisobutane and the bond dissociation energies of nitroso compounds

Study of the reaction by very‐low‐pressure pyrolysis (VLPP) in the temperature range of 550–850°K yields for the high‐pressure Arrhenius parameters\documentclass{article}\pagestyle{empty}\begin{document}$$\log {\rm }\,k_{\rm 1} = (15.6 \pm 0.5) - (36.0 \pm 1.0)/\theta {\rm \,(sec}^{{\rm - 1}})$$\end{document} where θ = 2.303 RT in kcal/mole. These in turn yield for the high‐pressure second‐order recombination of t Bu + NO, k −1 = (3.5 ± 1.7) × 10 9 1./mole·sec at 600°K. For the competing reaction l./mole·sec and E 4 ≥ 4.2 kcal/mole. The bond dissociation energy DH o ( tBu ‐NO) was determined to be (39.5 ± 1.5) kcal/mole, both from the equilibrium constant and from the activation energy of reaction (1), obtained from RRKM calculations. A ‘free‐volume’ model for the transition state for dissociation is consistent with the data. A limited study of the system at 8–200 torr showed an extremely rapid inhibition by products and a very complex set of products.