Methyl iodide → (S)-Benzyl 3-((tert-butoxycarbonyl)(methyl)amino)pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a suspension of 60% dispersion of sodium hydride in mineral oil (1.5 g, 37.5 mmol) in anhydrous DMF (20 mL) cooled on an ice-bath to 0° C. was added dropwise a solution of (S)-benzyl 3-(tert-butoxycarbonylamino)pyrrolidine-1-carboxylate (10 g, 31.2 mmol) in anhydrous DMF (100 mL). The resulting mixture was stirred at 0° C. for 1 hour then at ambient temperature for 2 hours. The mixture was subsequently cooled to 0° C. and treated dropwise with iodomethane (2.1 mL, 34.3 mmol), and the mixture stirred at 0° C. for 1 hour then warmed to ambient temperature and stirred for 18 hours. The reaction mixture was diluted with water (300 mL) and the mixture extracted with ethyl acetate. The combined organic layers were washed with water and brine, dried (MgSO4), filtered and concentrated under reduced pressure. The residual oil was purified by column chromatography (Biotage, 65M; 10-20% ethyl acetate:hexanes) to afford (S)-benzyl 3-(tert-butoxycarbonyl(methyl)amino)pyrrolidine-1-carboxylate (7.2 g, 69%).

Provenance & Evidence