10.6 g (50 mmol) 4-Chloro-1-(4-methoxy-phenyl)-butan-1-one, 20 ml 2-methyl-2-butanol, 5.2 g (75 mmol) 1H-[1,2,3]-triazole, 9.5 g (57 mmol) potassium iodide and 3.0 g (75 mmol) NaOH were stirred at 100° C. for 4 h. After removal of solvents in vacuo, the residue was partitioned between toluene and water. Washing of the toluene phase twice with water, drying over sodium sulphate and evaporation gave an oily residue that was dissolved in 80 ml diisopropyl ether/ethyl acetate (1:2). The solution was kept at 20° C. during the addition of 2.8 ml methanesulfonic acid and stirred at room temperature for 2 h. The formed precipitate was isolated, washed with cold diethyl ether and dried at 40° C. in vacuo to give 1-(4-methoxy-phenyl)-4-[1,2,3]triazol-1-yl-butan-1-one methanesulfonate. Yield: 2.25 g (13%).
