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Kinetics and Catalysis

, Volume 41, Issue 3, pp 293–297 | Cite as

The role of triplet repulsion in alkyl radical addition to a 7π-C-O bond and alkoxy radical addition to a π-C-C bond

  • E. T. Denisov
Article

Abstract

The experimental activation energies of the R + O = CR1R2 and RO + CH2 = CHR1 addition reactions are analyzed within the framework of the parabolic model of the bimolecular addition reaction. The activation energy also depends on the dissociation energy of the forming C-O bond and on the reaction enthalpy: the higher the dissociation energy, the higher the activation energy. The empirical relationshipr e J..D e = 0.97 x 10-13 m kJ.-1 mol is found for H, Cl, Br and RO radical addition to multiple C=C and C=O bonds (re is the distance between the peaks of the intersecting parabolic curves). This is due to the effect of the triplet repulsion on radical addition. The interaction of polar groups and the steric effect also influence the activation energy.

Keywords

Activation Energy Reaction Center Dissociation Energy Radical Addition Addition Reaction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© MAIK “Nauka/Interperiodica” 2000

Authors and Affiliations

  • E. T. Denisov
    • 1
  1. 1.Institute of Problems of Chemical PhysicsRussian Academy of SciencesMoscow oblastRussia

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