A process for the preparation of thiophenols of formula (I) wherein n is an integer from 1 to 5 and R is hydrogen, alkyl, hydroxyalkyl, alkylamino, dialkylamino, alkenyl, alkynyl, alkoxy, alkylthio, phenyl, naphthyl, phenoxy, phenylthio, halogen, hydroxy, mercapto, carboxyl, sulfo or heterocyclyl, by reacting phenyldiazonium salts of formula (II) wherein n and R are as defined and X is halogen or hydrogen sulfate, with sulfur at elevated temperature in the presence of an aqueous base and isolating the compounds of formula (I).