(Diethylamino)sulfur trifluoride → (2R,4S)-tert-butyl 2-(3-cyano-5-fluorophenyl)-4-fluoropyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of (2R,4R)-tert-butyl 2-(3-cyano-5-fluorophenyl)-4-hydroxypyrrolidine-1-carboxylate (I-13A) (0.7 g, 2.3 mmol) in DCM (4 mL) in a plastic bottle at −78° C. was added DAST (0.6 mL, 4.6 mmol). The reaction was stirred at −78° C. for 2 hours and then loaded directly onto silica gel and purified by column chromatography with EtOAc/hexanes gradient as eluant to yield (2R,4S)-tert-butyl 2-(3-cyano-5-fluorophenyl)-4-fluoropyrrolidine-1-carboxylate (I-14). 1H NMR (400 MHz, CDCl3) δ 7.35 (s, 1 H), 7.30-7.16 (m, 2 H), 5.25 (d, J=52.0 Hz, 1 H), 5.06-4.86 (m, 1 H), 4.20-3.98 (m, 1 H), 3.72 (dd, J=11.6, 38.8 Hz, 1 H), 2.80-2.66 (m, 1 H), 2.06-1.78 (m, 1 H), 1.45 (bs, 3 H), 1.19 (bs, 6 H). MS m/z 331.1 (M+23)+.

Provenance & Evidence