Kinetic studies in strongly basic glycolic solutions. Part II. Alkaline degradation of p-dinitrobenzene

Abstract

The alkaline degradation of p-dinitrobenzene (p-DNB) has been studied in EG–LiOG, EG–NaOG, and EG–KOG systems (EG = ethylene glycol; OG = glycolate). The observed first-order rate constant (k) for the reaction for C_MOGc_p-DNB increased much more rapidly than c_MOG in each system. The plots of log k against the H_– acidity function for the respective system set up with amine indicators, (H_–)_Am^EG, were linear with slopes of 0·96, 0·98, and 0·90 respectively. The plots of log k against (H_–)_Am^EG+ log c_GOH(c_GOH being the concentration of free glycol) for the respective system were also found to be linear with slopes of 1·00, 1·04, and 1·00 respectively, suggesting an S_N2 mechanism for the reaction as in the case of aqueous and methanolic media. The kinetics of the reaction have also been studied in the system EG–dimethylformamide–0·01M-NaOG and the mechanism in this medium seems to be same as in the EG–MOG systems.