Hydrotrope-induced autocatalysis in the biphasic alkaline hydrolysis of aromatic esters

The alkaline hydrolysis of aromatic esters exhibits autocatalytic kinetics when performed under two-phase conditions without any mixing solvent. The molecular structures of such aromatic esters determine whether the autocatalysis occurs or not. It has been established that enhancing the solubility of the hydrophobic ester in water by the hydrotropic salts yielded by the hydrolysis itself accelerates the apparent reaction rate. By kinetically independent measurements, the solubilization process of the ester was verified to be the rate-determining step. It has been observed that the Solubilization process can be influenced by factors such as the initial addition of hydrotropic salt, the volumetric ratio of the oil/aqueous phase, and the concentration of alkali. (C) 2002 Elsevier Science (USA).