In an atmosphere of argon, a mixture consisting of o-anisidine (500 mg, 4.06 mmol), triethylamine (1.6 ml, 11.5 mmol) and 2-bromomethyl-1,3-dioxolan (0.96 ml, 8.18 mmol) was stirred at 80° C. for 4 days, dissolved in methylene chloride (8 ml) and then, with cooling in an ice bath, mixed with 20% sodium hydroxide aqueous solution (4 ml) and 4-chloromethylbenzoyl chloride (768 mg, 4.06 mmol). After 1 hour of stirring at the same temperature, the resulting mixture was extracted with methylene chloride, washed with 10% citric acid aqueous solution and saturated brine and then dried on anhydrous sodium sulfate. Thereafter, the solvent was removed by evaporation, and the resulting residue was purified by subjecting it to a silica gel column chromatography (ethyl acetate:hexane=2:5) to obtain 704 mg (47.9%) of the title compound in the form of colorless solid.
