Effect of mixed H2O-CH3CN solvent on intramolecular general base-catalyzedcleavage of ionized phenyl salicylate in the presence of DL-proline

Citation
Mn. Khan et al., Effect of mixed H2O-CH3CN solvent on intramolecular general base-catalyzedcleavage of ionized phenyl salicylate in the presence of DL-proline, REACT KIN C, 67(2), 1999, pp. 253-259
Citations number
19
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
REACTION KINETICS AND CATALYSIS LETTERS
ISSN journal
01331736 → ACNP
Volume
67
Issue
2
Year of publication
1999
Pages
253 - 259
Database
ISI
SICI code
0133-1736(199907)67:2<253:EOMHSO>2.0.ZU;2-4
Abstract
Nucleophilic second-order rate constant (kn(ms)) for the reaction of DL-pro line with ionized phenyl salicylate (PS-) shows a nonlinear decrease with t he increase in the content of CH3CN in mixed aqueous solvents at less than or equal to 50 % v/v CH3CN. The values of knms show a mild increase with th e increase in the content of CH3CN at > 50 % v/v CH3CN. The effect of solve nt on k(n)(ms) is explained in terms of solvent effect on the pK(a) of the conjugate acids of leaving group ( i.e. phenolate ion) and DL-proline.