Reversible N-N Bond Homolysis in (CF3S)2N-N(SCF3)2 at Room Temperature. Electron Spin Resonance, Thermodynamic, and Kinetic Results

Article abstract of DOI:10.1021/ja00344a015

In perhaloalkane solvents at 250-315 K (CF3S)2N-N(SCF3)2 undergoes reversible homolytic cleavage reaction to yield (CF3S)2N* radicals which were identified by ESR.From the dependence of the stationary concentration of (CF3S)2N* on temperature the N-N bond dissociation energy is determined to be 32 +/- 2 kJ/mol (7.7 kcal/mol).At 298 K the equilibrium constant for N-N homolysis is (4 +/- 2) * 10^-6 M.The change in entropy occuring on N-N homolysis corresponds to 3 J/K mol (0.7 eu).The activation enthalpy and entropy for N-N bond cleavage are 77 kJ/mol (18.4 kcal/mol) and 5 J/K mol (1 eu), respectively.The experimental results concerning the facile N-N homolysis are interpreted in terms of sterically and electronically induced destabilisation of the N-N bond in (CF3S)2N-N(SCF3)2.