Effect of cyclodextrin on the intramolecular catalysis of aryl hydrogen phthalate ester hydrolysis

Abstract

The classic explanation of the anisotropic effect of the single bond is not valid. An alternative, ab initio calculated model is proposed in agreement with experimental data.

Mechanism of phthalate ester hydrolysis in water and in cyclodextrin mediated reactions

“…The reaction of this substrate has contribution from the intramolecular catalyzed reaction and the OH -catalyzed reaction, but we can subtract the contribution from the intramolecular reaction since we know this rate from previous work. 20 The results indicate that the reaction of OH -with this ester is also strongly inhibited, therefore we can discard the mechanism described in Scheme 2. The mechanism must be the one shown in Scheme 3 were an external OH -react with the complexed substrate and this reaction is slower than that corresponding to the substrate free in solution.…”

“…20 All reactions were run at (25.0 ± 0.1) ºC and at constant ionic strength (0.5 M) using NaCl as compensating electrolyte.…”

Acceleration of Thiol Ester Hydrolysis by Cyclodextrins: Evidence from Rate and Computational Studies

“…[16] Hydrolysis of phthalic anhydride and different substituted aryl hydrogen phthalate esters are also studied. [17,18] The hydrolysis of phthalic anhydride is catalyzed by buffer bases and that of phthalate esters occurs with the formation of phthalic anhydride as the intermediate. Phenyl esters of perfluoroalkanoic acids (with different fluoroalkyl chains) undergo β-CD-mediated hydrolysis involving shifts in the mechanism because of different modes of inclusion of the substrate inside the CD cavity.…”