Negative activation energies and compensation effects for the reactions of diarylaminyl radicals with phenols
作者:V. T. Varlamov、N. N. Denisov、V. A. Nadtochenko
DOI:10.1007/bf00713594
日期:1995.12
The temperature dependence of the rate constants of the reaction of 4,4'-disubstituted diphenylaminyl radicals (ArAr'N-.) with phenols has been studied by a laser pulse photolysis technique. The linear relationships between activation energies E(1) (negative in the majority of cases) and logarithms of pre-exponential factors logA(1) have been established. These results coincide with the two-parametric correlations of logk(1) with sigma(+) constants of substituents in phenol and aminyl radicals under isothermal conditions. The reaction rate constants decrease considerably when toluene is used instead of n-decane.