Nitrogen → (3R)-3-Fluoro-1-pyrrolidinebutanamine

Participants

Reaction Steps

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), to a solution of (R)-3-fluoropyrrolidine hydrochloride (400 mg, 3.09 mmol) and 4-bromobutyronitrile (0.32 mL, 3.09 mmol) in dry CH3CN (16 mL) was added K2CO3 (2.35 g, 16.99 mmol) at rt followed by KI (51 mg, 0.31 mmol). The reaction mixture was stirred at rt for 15 h. The mixture was filtered and the filtrate partitioned between water and CH2Cl2. The layers were separated and the aq. layer extracted with CH2Cl2 (3×). The combined org. extracts were dried over MgSO4, filtered and concentrated under reduced pressure. The crude nitrile was redissolved in dry THF (23 mL) and treated with LiALH4 (214 mg, 5.47 mmol) at 0° C. The reaction mixture was warmed up to rt and stirred at this temperature until completion of the reaction. Aq. 1N NaOH (7 mL) was then added, the layers separated and the aq. layer extracted with EA (3×). The combined organic extracts were washed with brine, dried over Na2SO4, filtered, and the solvents were removed under reduced pressure to give crude (R)-4-(3-fluoropyrrolidin-1-yl)butan-1-amine as a colorless oil. GC-MS-conditions 01: tR=1.71 min; [M+H]+=161.10.

Provenance & Evidence