2524-49-4

24424-99-5

156731-40-7

General procedure: synthesis of intermediate 62. tert-butyl but-3-en-1-yl carbamate. Triethylamine (1.80 mL, 12.98 mmol) was added to a solution of but-3-en-1-amine (700 mg, 9.84 mmol) in dichloromethane (10 mL). The mixture was cooled to 0 °C and di-tert-butyl dicarbonate (2.7 g, 12.37 mmol) was added batchwise under nitrogen protection. The reaction mixture was gradually warmed to room temperature and stirring was continued for 16 hours. Upon completion of the reaction, the solvent was removed by evaporation and the residue was redissolved in ether (20 mL). The organic phase was washed sequentially with saturated aqueous ammonium chloride solution (2 x 20 mL) and brine, dried over anhydrous sodium sulfate, filtered and concentrated to dryness to afford 1-(Boc-amino)-3-butene as a colorless oil (1.68 g, 100% yield).LRMS (m/z): 172 (M + 1)+.