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 where θ = 2.303RT in kcal/mole. These in turn yield for the high-pressure second-order recombination of tBu + NO, k_?1 = (3.5 ± 1.7) × 10⁹ 1./mole·sec at 600°K. For the competing reaction l./mole·sec and E₄ ≥ 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.