Triethylamine → Dodecylamine

Participants

Reaction Steps

To a 0° C. solution of 4-amino-1-benzylpiperidine 11 (41.2 g, 216.5 mmol) and triethylamine (51.3 mL, 369 mmol) in 600 mL of tetrahydrofuran was added benzyl chloroformate (31 mL, 217 mmol) dropwise over a period of 30 to 45 min. at such a rate that the reaction temperature was kept between 5° C. and 10° C. After the addition was complete, the reaction mixture was allowed to warm to room temperature and stir for 12 hours. The solvent and volatiles were removed under reduced pressure. Water (500 mL) and ethyl acetate (1.2 L) were then added and the reaction was partitioned between the two phases. The organic layer was washed with saturated aqueous sodium bicarbonate solution (2×, 150 mL) and then dried (brine, MgSO4). Evaporation of the solvent yielded a tan liquid which was purified via column chromatography (SiO2, EtOAc/Hexane-30/70 to EtOAc-100) to provide 27.8 g of the amine 12 as a white solid (mass spec. M+=324, MP=79.1–79.6° C.).

Provenance & Evidence