Selectivity in the Base-Catalyzed Hydrolysis of p-Nitrophenyl Esters within a Reversed-Phase Liquid Chromatography Column

Article abstract of DOI:10.1021/jo00252a020

The ^-OH-catalyzed hydrolyses of p-nitrophenyl acetate (1) and hexanoate (2) were performed with excess ^-OH on a reversed-phase liquid chromatography column of macroporous 10-μm poly(styrene-divinylbenzene) under HPLC conditions to give pseudo-first-order rate constants k_ψ.The maximum value of k_ψ¹/k_ψ² was <*> 25, and the reactivity difference was attributed to different rates of desorption of 1 and 2 from the polymer surface into the mobile phase, ^-OH was localized.The results demonstrated that a polymer-based, reversed-phase HPLC column can impart selectivity to the reactions of an ionic, inorganic reagent with neutral, organic substrates that have comparable intrinsic reactivities but different relative hydrophilic/lipophilic characters.