Sodium hydride → HCID 118331283, compound

Participants

Reaction Steps

To a solution of (S)-tert-butyl (2-oxopyrrolidin-3-yl)carbamate (250 mg, 1.25 mmol) in DMF (5 mL) at 0° C. was added sodium hydride (52.9 mg, 1.32 mmol). After stirring at rt for 1 h, 2,2,2-trifluoroethyl trifluoromethanesulfonate (0.18 mL, 1.25 mmol) was added then the reaction mixture was allowed to warm to rt and stirred for 3.5 h. The reaction mixture was concentrated under reduced pressure and the residue purified on silica gel eluting with 0 to 75% EtOAc/DCM to give Compound 91a (95 mg, 27% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ 5.11 (br. s., 1H), 4.24 (br. s., 1H), 4.07 (dq, J=15.0, 9.2 Hz, 1H), 3.91-3.67 (m, 1H), 3.63-3.37 (m, 2H), 2.84-2.47 (m, 1H), 2.12-1.84 (m, 1H), 1.53-1.42 (m, 9H). COSY NMR shows coupling of NH at 5.11 ppm to methine at 4.24 ppm, confirming regioselectivity of alkylation on the pyrrolidinone nitrogen. US 2009/760005 A1.

Provenance & Evidence