Influence of the activation entropy on the change of the isokinetic temperature in the S(N)2 reactions in solution

摘要

The increase of the changes in the activation entropy .S. value leads to the decrease of the isokinetic temperature Tiso value for the -SN2 reaction series in which structure changes are introduced in the substrate, in the reagent or in the solvent. The changes of the free energy of activation .G. exp and the activation entropy .S. in the frameworks of the isokinetic relationship .G. exp vs. T iso -T exp .S. were explored quantitatively to predict the isokinetic temperature Tiso for the -SN2 reactions in different solvents.