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 = 2.303RTin kcal/mole. These in turn yield for the high‐pressure second‐order recombination oftBu + NO,k−1= (3.5 ± 1.7) × 1091./mole·sec at 600°K. For the competing reaction l./mole·sec andE4≥ 4.2 kcal/mole. The bond dissociation energyDHo(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.