effects of solvent?
in the study of reaction mechanism .
detailed
Answers
A really effective way to get in-depth information about the effect induced by different solvents on the evolution of a given reaction is to perform Linear Solvation Energy Relationships (LSER) studies. The approach requires the collection of a relevant number of either kinetic (rate constant, kv) or thermodynamic (equilibrium constants, Ke) determinations (at least 13-15) related to the reaction to be studied as a function of the employed medium which, in turn, can be represented by solvents in both pure and mixed fashion. The measured Ln(kv) or Ln(Ke) values must then to be reproduced through equations in which are incorporated several descriptors of solvent-effects specific for each analyzed medium (they are normally available by literature), whose single contributions are modulated by factors achieved through suitable linear regression.
By way of example, detailed information about approaches of type LSER are effectively discussed in “Principles and Methods in Supramolecular Chemistry”, by Hans-Jorg Schneider e Anatoly K. Yatsimirsky (WILEY), while typical examples of application can be found in the following two articles:
1) “Stereolability of dihydroartemisinin, an antimalarial drug: a comprehensive thermodynamic investigation. Part 1.”
W. Cabri, I. D'Acquarica, P. Simone, M. Di Iorio, M. Di Mattia, F. Gasparrini, F. Giorgi, A. Mazzanti, M. Pierini, M. Quaglia, C. Villani
The Journal of Organic Chemistry, 2011; 76, 1751-8;
2) “Determination of the polarities of some ionic liquids using 2-nitrocyclohexanone as the probe.”
G. Angelini, C. Chiappe, P. De Maria, A. Fontana, F. Gasparrini, D. Pieraccini, M. Pierini, G. Siani
The Journal of Organic Chemistry, 2005; 70, 8193-6.