KINETICS AND MECHANISM OF THE ACID-CATALYZED HYDROLYSIS OF BENZALDEHYDE DIARYL THIOACETALS AND OF BENZALDEHYDE S-ARYL, S-ETHYL ACETALS IN AQUEOUS PERCHLORIC-ACID

The effects on the rate of hydrolysis of changes in aryl substituents, acid concentration, temperature, and solvent isotope, show that the acid-catalysed hydrolyses of five benzaldehyde diaryl thioacetals and three benzaldehyde S-aryl, S-ethyl acetals in 2-7 mol dm-3 aqueous perchloric acid proceed via essentially A1 mechanisms. The pattern of the substituent effects found for the leaving, and remaining, S-aryl groups is similar to that found previously for leaving and remaining groups in O,O- and O,S-acetals.