48 g (0.3 mol) of bromine were added dropwise to 110.5 g (0.3 mol) of 1-(4-chlorophenoxy)-4-(4-chlorophenylmercapto)-3,3-dimethyl-butan-2-one in 750 ml of carbon tetrachloride at room temperature. The mixture was subsequently stirred at room temperature for one hour and was concentrated by distilling off the solvent in vacuo, and the residue was taken up in 750 ml of toluene. 73 g (1.06 mol) of 1,2,4-triazole and 150 g (1.06 mol) of potassium carbonate were added to this solution. The mixture was heated to 90° C. for 8 hours and allowed to cool to room temperature and the organic phase was separated off. This phase was extracted with dilute sodium hydroxide solution, rinsed with water, dried over sodium sulphate and concentrated in vacuo. 34 g (26% of theory) of 1-(4-chlorophenoxy)-4-(4-chlorophenylmercapto)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)-butan-2-one of melting point 115° C. were obtained.
