Cyclopropylamine → tert-Butyl 4-(cyclopropylamino)piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of tert-butyl 4-oxopiperidine-1-carboxylate 90.3 g, 1.5 mmol) in dichloroethane (10 mL) was add cyclopropylamine (0.13 mL, 1.95 mmol), sodium triacetoxyborohydride (0.48 g, 2.26 mmol) and a few drops of acetic acid. The reaction mixture was stirred at ambient temperature overnight. The reaction mixture was then diluted with dichloromethane and washed with NaHCO3 solution. The organic phase was separated and then dried over MgSO4. Following concentration, the residue was chromatographed on silica gel eluting with 5% methanol/dichloromethane to yield the title compound. 1H NMR (300 MHz, CDCl3) δ ppm 4.03 (d, J=12.21 Hz, 2 H), 2.79 (m, 3 H), 2.14 (m, 1 H), 1.91 (d, J=12.55 Hz, 2 H), 1.69 (m, 2 H), 1.46 (m, 9 H), 1.27 (m, 2 H), 0.47 (m, 2 H), 0.36 (m, 2 H).

Provenance & Evidence