Hydrolysis of Aldal Acetals

Article abstract of DOI:10.1021/jo00346a004

Eleven aldal acetals were synthesized, and the kinetics of their hydrolyses in water and in water-acetonitrile were studied as model systems for the hydrolysis of sucrose. α,α'-Diethoxypropyl ether (an aldal acetal) hydrolyzes in water without hemiacetal buildup.The reaction is not subject to general acid catalysis and the value of k_D3O(+)/k_H3O(+) = 2.44, both results being characteristic of an A1 mechanism.The energy of activation for the hydrolysis of α,α'-diethoxydipropyl ether was 84.98 kJ mol ^-1 in water and showed no temperature dependency over the range of 15 - 35 deg C.The structural effects for the hydrolysis of aldal acetals parallel those for acetal hydrolysis.