128372-89-4

1215765-59-5

128372-89-4

A 30% H2O2 solution (2.2 mL, 36 mmol) was slowly added to a stirred tert-butyl 2-oxo-3-(phenylseleno)piperidine-1-carboxylate (4.27 g, 12 mmol) in THF solution (20 mL) at 0 °C. The reaction mixture was continued to be stirred at 0 °C for 15 min, followed by slow warming to room temperature and maintained for 30 min. Upon completion of the reaction, the mixture was dissolved in CH2Cl2 (200 mL) and washed with saturated NaHCO3 solution. The organic phase was dried and concentrated to afford the target product tert-butyl 2-oxo-5,6-dihydropyridine-1(2H)-carboxylate (2.1 g, 88.6% yield).