ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The kinetics of hydrolytic cleavage of saccharin has been studied at 60°C within the [ŌH] range of 0.1 to 3.0 M. The observed pseudo first-order rate constants, kobs, follow an empirical relationship: kobs = B[ŌH] + [C[ŌH]]2. The B and C terms are attributed to the formation of dianionic and trianionic tetrahedral intermediates on the reaction path. It is concluded that the ionized form of saccharin is the major reacting species under the present experimental conditions. The positive ionic strength effect and the negative effect of 1,4-dioxan on the rate of hydrolysis favor the proposed reaction mechanism. The analysis of the observed activation parameters indicates that the increase in the contribution of C term to kobs causes the slight increase in both ΔH* and ΔS*. A significantly large negative value of ΔS* favors the proposed mechanism.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/kin.550181005