3,5-Bis(t-butyl)-1-(bromomethyl)benzene (170 mg, 0.60 mmol), t-butyl piperazine carboxylate (102 mg, 0.55 mmol) and potassium carbonate (151 mg, 1.10 mmol) were dissolved in a solvent mixture of acetone (2 ml) and DMF (0.2 ml), and the mixture was stirred overnight while heated under reflux. The reaction mixture was extracted with ethyl acetate, dried over sodium sulfate, and then the filtrate was evaporated under reduced pressure. The concentrate was subjected to silica gel column chromatography (n-hexane:ethyl acetate=4:1) to give 120 mg (yield: 56%) of the title compound as a white solid.
