Trifluoroacetic acid → (2R,4S)-4-fluoro-2-(3-fluorophenyl)pyrrolidine

To a solution of (2R,4S)-tert-butyl 4-fluoro-2-(3-fluorophenyl)pyrrolidine-1-carboxylate (I-5A) (890 mg, 3.14 mmol) in DCM (5 mL) at room temperature was added TFA (5 mL). The mixture was stirred at room temperature for 2 hours. All the solvents were removed under reduced pressure. The crude was extracted with EtOAc, washed with aqueous NaHCO3 and brine, dried over sodium sulfate, filtered and concentrated to yield (2R,4S)-4-fluoro-2-(3-fluorophenyl)pyrrolidine (I-6). 1H NMR (400 MHz, CDCl3) δ 7.31-7.25 (m, 1 H), 7.15-7.10 (m, 2 H), 6.96-6.90 (m, 1 H), 5.29 (d, J=53.6 Hz 1 H), 4.50 (dd, J=9.6, 6.4 Hz, 1 H), 3.43-3.33 (m, 1 H), 3.31-3.28 (m, 1 H), 2.51 (ddd, J=21.2, 14.0, 6.4 Hz, 1 H), 2.23 (bs, 1 H), 1.79 (dddd, J=39.6, 14.4, 10.0, 4.4 Hz, 1 H). MS m/z 184.1 (M+1)+.

1. customAll the solvents were removed under reduced pressure
2. extractionThe crude was extracted with EtOAc
3. washwashed with aqueous NaHCO3 and brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated

ORD record

ord-38e37a8468be4e9fa6bc93dfae03aefb

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09102671B2