Furfural → HCID 22498771, Verbindung

N-Boc-pyrrolidine (5.0 g) was dissolved in diethyl ether (60 mL) and the solution was cooled to −78° C. N,N,N′,N″-Tetramethylethylenediamine (TMEDA) (4.4 mL) was added to the mixture followed by sec-butyl lithium (27.0 mL, 1.3 M in cyclohexane) maintaining the temperature below −60° C. After 2 h, 2-furaldehyde (2.9 mL) was added and the mixture was stirred at −70° C. for an additional 30 min. The reaction mixture was allowed to warm to room temperature and was then quenched with water and poured into EtOAc (200 mL). The separated organic layer was washed with saturated aq. ammonium chloride (3×50 mL) followed by brine (50 mL), dried (MgSO4), and concentrated. The crude product was purified by column chromatography (heptane/EtOAc, 8/1; 5/1) to afford 4.97 g of 2-furyl(N-Boc-pyrrolidin-2-yl)methanol as a mixture of diastereomers. The resulting 2-furyl(N-Boc-pyrrolidin-2-yl)methanol (4.43 g) was dissolved in dichloromethane (200 mL) and trifluoroacetic acid (30 mL) was added. The mixture was poured into a 1 M solution of sodium hydroxide. The organic layer was separated and washed with saturated aq. sodium bicarbonate (2×100 mL). The aqueous layers were extracted with dichloromethane (4×50 mL) and the combined organic layers were concentrated. The crude product was purified by column chromatography (CH2Cl2/methanol/NH4OH, 95/5/1; 90/10/1). The resulting oil was distilled in a Kugelrohr apparatus (175-200° C., 0.2 Torr) to afford 0.20 g of the title compound as a mixture of diastereomers. Physical characteristics. MS (ESI+) m/z 168 (M+H)−.