Acetaldehyde → Tert-butyl 3-(ethylamino)pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of (R)-3-amino-1-N-Boc pyrrolidine (1 eq, 5.37 mmol) in methanol (20 mL) was added acetaldehyde (0.95 eq) and the resulting mixture was heated to 80° C. and stirred for 2 h., then stirred at room temperature overnight. Sodium borohydride (0.95 eq, 5.1 mmol) was added and reaction mixture was stirred for an additional 2 h. The reaction mixture was concentrated, dissolved in ethyl acetate and washed with saturated aqueous sodium bicarbonate. The combined organics were washed with brine and dried over sodium sulfate. The crude product was purified on silica using hexane/ethyl acetate (10%) to hexane/ethyl acetate (50%). 1H-NMR (CDCL3) δ: 1.05 (3H, t), 1.45 (9H, s), 1.60-1.75 (1H, m), 2.00-2.10 (1H, m), 2.68 (4H, q), 2.90-3.15 (1H, m), 3.25-3.65 (4H, m). ESI-MS m/z: 215 (M+1), UV retention time: 0.75 min.

Provenance & Evidence