To a solution of 2-(4-(6-chloro-2-methylpyrimidin-4-yl)piperazin-1-yl)ethanol obtained in Step A (1.00 g) and imidazole (0.636 g) in N,N-dimethylformamide (13 mL) was added tert-butyl(chloro)dimethylsilane (0.793 g) at room temperature, and the mixture was stirred for 2 hr. The reaction mixture was poured into water, and the mixture was extracted with ethyl acetate. The extract was washed with water and saturated brine, and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure to give the title compound (1.42 g).
