tert-Butyl 4-(4-cyanophenoxy)piperidine-1-carboxylate

767-00-0

118811-07-7

333954-86-2

Step (i): preparation of tert-butyl 4-(4-cyanophenoxy)piperidine-1-carboxylate 4-Hydroxybenzonitrile (15 g, 0.126 mol), potassium carbonate (28.89 g, 0.208 mol) and tert-butyl 4-(toluene-4-sulfonyloxy)piperidine-1-carboxylate (57.62 g, 0.162 mol) were dissolved in dimethylformamide (150 mL), and the reaction was stirred at 100 °C. The progress of the reaction was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction mixture was quenched by pouring into water (400 mL) and extracted with ethyl acetate (3 x 300 mL). The combined organic layers were washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give the crude product. The crude product was purified by fast column chromatography with the eluent ethyl acetate:hexane (1:9) to afford 21.25 g (yield: 55.8%) of the title compound. 1H NMR (δ ppm): 1.47 (9H, s), 1.74-1.80 (2H, m), 1.91-1.96 (2H, m), 3.33-3.40 (2H, m), 3.66-3.72 (2H, m), 4.53-4.57 (1H, m), 6.94-6.96 (2H, d, J = 8.78 Hz), 7.57-7.59 (2H, d, J = 8.76 Hz). Mass spectrum (m/z): 303.4 (M + H)+.