A new derivatization reagent 2-(pentafluorophenoxy)ethyl 2-(piperidino)ethanesulfonate for gas chromatography

A new sulfonate reagent 2-(pentafluorophenoxy)ethyl 2-(piperidino)-ethanesulfonate (PFPES), structurally having an electrophore and a tertiary amino function, was synthesized for the analytical derivatization in gas chromatography (GC). The reagent is reactive to n-valeric acid, valproic acid, benzoic acid, 2-mercaptoethanol, phenol, thiophenol, ethosuximide and chlorpropamide in a liquid-solid reaction system, and also reactive to iodide, cyanide, nitrite and thiocyanate anions in a liquid biphasic reaction system, all checked by thin layer chromatography (TLC). After derivatization of the analytes in the toluene phase, the excess PFPES can be easily removed from the toluene layer by a simple aqueous acid treatment. This can minimize the interference of excess PFPES in GC separation and detection. Application of the reagent to the derivatization of n-valeric acid and iodide anion as test analytes for capillary GC-electron capture detector (GC-ECD) was performed. The resulting derivatives are highly responsive to an ECD. The detection limits in per injection of n-valeric acid and iodide anion are about 170 fmol (in 0.6 mu l) and 15 fmol (in 0.3 mu l), respectively. (C) 1999 Elsevier Science B.V. All rights reserved.