DEGRADATION STUDY OF UNSATURATED ANHYDRIDES BY REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

In this report, the applicability of reversed-phase high-performance l iquid chromatography (HPLC) to the degradation and kinetic studies of unsaturated anhydrides is explored. Under the appropriate HPLC conditi ons, the separation and determination of anhydrides were achieved. Aft er comparing their stabilities in methanol, acetonitrile and pure wate r, the hydrolytic behavior of anhydrides was further evaluated using v arying proportions of aqueous phase and acidity for hydrolysis. On the basis of a nucleophilic-attack pathway, the stability and hydrolytic velocity of the anhydrides were compared. The results showed that the hydrolytic processes of the anhydrides could be described with first-o rder equations, and the corresponding hydrolytic rate constants were c alculated from the experimental data. (C) 1998 Elsevier Science B.V.