MICELLAR-MEDIATED GENERAL ACID-CATALYZED ACETAL HYDROLYSIS - REACTIONS IN COMICELLES

Anionic micelles of sodium dodecyl sulfate (SDS) increase the rates of acid hydrolyses of dibutyl and di-tert-butyl benzaldehyde acetal (BBA and BTBA, respectively), The rate surfactant profiles are fitted by a pseudophase, ion-exchange, model and second-order rate constants in t he micellar pseudophase are slightly lower than in water. In both medi a BTBA is considerably more reactive than BBA, The reaction of BTBA is general acid catalysed and with micellar-bound BTBA the first-order r ate constant of hydrolysis in comicelles of SDS and sodium decyl hydro genphosphate increases linearly with increasing mole fraction of the p hosphate surfactant, which is a general acid catalyst in the micellar pseudophase. However, the rate constant of the specific hydrogen ion c atalysed hydrolysis of BBA is independent of the mole fraction of the phosphate surfactant.