Abstract

---

This article presents results of the aqueous hydrolyses of propionic and butyric anhydride between 0 and 60°C in mildly acidic solutions of varying propanoate and butanoateconcentrations, respectively. These studies focus specifically on the temperature effectsand analysis of the activation parameters. The primary goal of this work is to establish mechanistic trends for simple and general-base catalyzed hydrolysis of smaller anhydrides, and to reevaluate conventional conclusions on certain modeling features. Resultsstrongly support a two-step mechanism for simple hydrolysisbelow room temperature,and a single-step mechanism for propanoate- and butanoate-catalyzed hydrolysis for all temperatures.Implications of these results and comparison with acetic anhydride hydrolysis are discussed.

---