Iodometric titration with the dead stop endpoint was used to determine the amount of alkylhydroperoxides in an oxidation reaction mixture composed of the hydrocarbon starting material, an alcohol, a ketone and an alkylhydroperoxide. Because alkylhydroperoxides decompose on glpc analysis, glpc could not be used for total analysis of the reaction mixture nor for the determination of thein situalcohol content. However, the addition of triphenylphosphine to a separate portion of the sample quantitatively produced the corresponding alcohol from the hydroperoxide without interfering with the ketone concentration. The total alcohol content of this portion could then be determined by glpc, and the initial alcohol content found by subtracting the amount of hydroperoxide from the total alcohol.