Investigation of isoprenoid benzoates and naphthoates by reversed-phase liquid chromatography : Isocratic elution characteristics of benzoates and naphthoates of C 5C 20 terpenoid alcohols

Abstract

Conditions for derivatization of C 5C 20 isoprenoid alcohols and the reversedphase liquid chromatographic properties of the corresponding benzoate and naphthoate esters are described. A non-linear response of log k' to changes in the composition of the mobile phase was observed on a RAdial-Pak C 18 column. In general, the capacity factors ( k') increased with increases in carbon content an degree of saturation inthe hydrocarbon chain, and decreased with increases in branching and Z double bond content. Replacement of a single hydrogen in the methyl group at C-3 of geranyl benzoate with fluorine had little effect on k', while the difluoro- and trifuoromethyl derivatives showed regular increases in k'. The large extinction coefficients of the aromatic ester moieties, especially the 2-naphthoates, provide high sensitivity for UV detection.