Cevasco, GiorgioGalatini, AndreaPirinççioğlu, NecmettinThea, SergioWilliams, Andrew2024-04-242024-04-242008Cevasco, G., Galatini, A., Pirinççioğlu, N., Thea, S. ve Williams, A. (2008). A study on a primitive artificial esterase model: Reactivity of a calix[4]resorcinarene bearing carboxyl groups. Journal of Physical Organic Chemistry, 21(6), 498-504.0894-3230https://doi.org/10.1002/poc.1371https://hdl.handle.net/11468/23200https://onlinelibrary.wiley.com/doi/10.1002/poc.1371The host molecule octacarboxymethyl calix[4]resorcinarene 1 catalyses the hydrolysis of substituted phenyl N-methylpyridinium-4-carboxylate esters 3a-f by complexation followed by intracomplex reaction via an anhydride intermediate. The reactivity in the presence of 1 is higher than that of the background at low pH; at high pH an inversion of reactivity occurs, the background becomes predominant since the host inhibits hydrolysis of the esters. The reactivity of esters 3a-f complexed with the host suffers little change in effective charge on the phenolic oxygen (-0.15 units) in contrast with the changes observed in alkaline hydrolysis (-0.28 units) and in the hydrolysis of the model monoaryl glutarate esters (-1.02 units). The less negative effective charge in the transition state for host 1 catalysis compared with that in the glutarate case is ascribed to stronger solvation by water molecules in the complex compared with that due to water molecules in the bulk solvent.eninfo:eu-repo/semantics/closedAccessCalixresorcinarenesCatalysisEster hydrolysisMolecular receptorsArticle2164985042-s2.0-4664909112610.1002/poc.1371Q3