Process for the preparation of N-(cyclohexylthio)-phthalimide

In the process of preparing N-(cyclohexylthio)-phthalimide by the reaction of one mol of phthalimide with one mol of cyclohexylsulphenylchloride in the presence of a base, the improvement which comprises employing an aqueous solution of alkali metal hydroxide or alkaline earth metal hydroxide as the base in an amount which supplies at least one mol of said base and up to a 10 mol % excess of said base, based on cyclohexylsulphenylchloride.