Quantitative determination of esters by saponification in dimethyl sulphoxide.

A method is given for the quantitative determination of esters which makes use of the unusually rapid rate of their alkaline hydrolysis in aqueous dimethyl sulphoxide medium. Only 5 min heating on a steam-bath is needed for quantitative hydrolysis of most esters, and many react completely in 5 min at room temperature. When hydrolysis is complete, the excess of base is titrated with standard acid, using a visual indicator.