Fluorescent Labeling Reaction of Carboxylic Acids with 4-Hydroxymethyl-7-methoxycoumarin in the Presence of Diethyl Azodicarboxylate and Triphenylphosphine

Abstract

A method for the fluorescent labeling of carboxylic acids with 4-hydroxymethyl-7-methoxycoumarin (I) in the presence of diethyl azodicarboxylate and triphenylphosphine is described. The reaction of aliphatic and aromatic acids with I at room temperature for fifteen minutes in tetrahydrofuran gave the corresponding esters in a good yield. Thin-layer chromatographic separation and fluorescent measurement of the esters allow the determination of carboxylic acids.