3-Arylcoumarins as fluorescent indicators

Abstract

A new group of fluorescent compounds, 3-arylcoumarins, were evaluated as indicators for various types of titrations. Several of the compounds were found to have a wide spectrum of applications, not only as adsorption indicators for precipitation titrations, but also as indicators for acid-base titrations. Some were found to be as effective as dichlorofluorescein in their adsorption indicator properties in precipitation titrations. Many were also found to compare favourably with some of the most efficient acid-base indicators such as phenolphthalein, methyl red and phenol red.