Ester hydrolysis: Conditions for acid autocatalysis and a kinetic switch

Autocatalysis can be used to obtain a sharp switch in state after a programmable time lag. Here, autocatalysis driven by acid concentration during the dissolution and hydrolysis of solid esters was investigated. In a generic model of the process, conditions were identified for observation of a kinetic switch with the introduction of an inhibitor species, bicarbonate, to delay the onset of autocatalysis. The kinetic profiles from the hydrolysis of two esters, d-gluconic acid δ-lactone and dl-lactide, were examined and evidence for dissolution-limited acid autocatalysis was obtained with lactide.