Under argon and at room temperature, imidazole (1.0 g, 15.0 mmol) and tert-butyldimethylsilyl chloride (1.7 g, 11.2 mmol) are added to a solution of 2-[3-(hydroxymethyl)benzyl]-1H-isoindole-1,3(2H)-dione (2.0 g, 7.5 mmol) in tetrahydrofuran (22.5 ml). The reaction mixture is stirred at room temperature for 16 h, and water is added. After addition of dichloromethane and phase separation, the aqueous phase is extracted with dichloromethane. The combined organic phases are dried (sodium sulfate), filtered and concentrated under reduced pressure. The desired product is purified by flash chromatography (petroleum ether/ethyl acetate mixtures). Yield: 2.7 g, 95% of theory.
