Free-radical abstraction reactions with concerted fragmentation and NO formation

The enthalpy and activation energy of reactions involving attack by MeO (2) (aEuro cent) and MeO (2) (aEuro cent) on CH2 groups of 2-butyl nitrite and 2-nitrosobutane have been calculated by quantum chemical methods. The abstraction of a hydrogen atom is accompanied, in the former case, by concerted N-O bond breaking and, in the latter case, by concerted C-N bond breaking, resulting in NOaEuro cent formation. On the basis of the results obtained, an algorithm has been developed within the intersecting parabolas model for calculating the enthalpies, activation energies, and rate constants of these types of reactions involving alkyl, alkoxyl, aminyl, peroxyl, phenoxyl, thiyl, and hydroxyl radicals.