Acetic Acid → tert-Butyl 4-(ethylamino)piperidine-1-carboxylate

Participants

Reaction Steps

Ethylamine HCl (6.14 g, 75.376 mmol, 1.5 eq) and tert-butyl 4-oxopiperidine-1-carboxylate (10.0 g, 50.25 mmol, 1.0 eq) were dissolved in MeOH (200 ml); acetic acid (0.2 ml) was added and stirring was carried out for 2 hours at RT. NaBH3CN (6.3 g, 100.50 ml, 2.0 eq) was then added in portions at 0° C. and the mixture was stirred for 14 hours at RT. The reaction mixture was concentrated and the residue was taken up in sat. sodium hydrogen carbonate solution (150 ml) and extracted with DCM (2×400 ml). The combined org. phases were washed with sat. NaCl solution (200 ml), dried over sodium sulfate and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel, 1% MeOH in DCM). Yield: 70% (8.0 g, 35.08 mmol)

Provenance & Evidence