Hydrolysis of active esters by polymer-supported oximes: Influence of macromolecular characters

Abstract

Hydrolysis of p-nitrophenyl acetate by oximino groups anchored onto two types of supports (i.e., polystyrene and polyacrolein) has been studied. Polystyrene and polyacrolein oximes were prepared using divinylbenzene and tetraethyleneglycol diacrylate as crosslinking agents with a varying extent of crosslinking. The rate of the esterolytic reactions was found to depend on the structural characteristics of the polymer support, which include the hydrophobic or hydrophilic nature of the polymer backbone, solvation of the polymer and the attached functional groups, the nature and extent of crosslinking of the polymer matrix, and also the chemical environments of the oximino groups. The effect of the presence of pyridine residues neighboring the acrolein oxime functionality on the hydrolysis reaction was also studied.