Titrimetric determination of some organic compounds by oxidation with bromine

Abstract

A simple, rapid and accurate titrimetric method for the determination of 0.1–10 mg of catechol, hydroquinone, o- and p-aminophenols and o-and p-phenylenediamines is described. The method is based on the oxidation of these compounds with saturated bromine water to give the corresponding benzoquinones, which liberate equivalent amounts of iodine when reacted with an excess of iodide. The liberated iodine is determined in the usual way, using starch as an indicator. The coefficient of variation does not exceed 1.1% for above 1 mg of the studied compounds, but increases up to 1.3% at the 0.1-mg level.