Benzyl Bromide → (S)-tert-butyl 1-benzyl-2-oxoazepan-3-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

To a stirring solution of (S)-tert-butyl 2-oxoazepan-3-ylcarbamate (250 mg, 1.10 mmol) in DMF (1 mL) was added a solution of 20 weight % LiHMDS in THF (870 mg, 1.04 mmol) at −70° C. under argon. The reaction mixture was stirred at −70° C. for 10 min followed by the addition of (bromomethyl)benzene (0.137 mL, 1.15 mmol) at the same temperature. Then the reaction was allowed to stir at rt for 30 min. The reaction was quenched with water and extracted with EtOAc. The organic layer was washed with water, saturated aqueous NaCl, dried over MgSO4, filtered and concentrated. The crude product was purified using silica gel chromatography (ISCO system) eluting with a gradient of 0-80% EtOAc/Hex to give (S)-tert-butyl 1-benzyl-2-oxoazepan-3-ylcarbamate (300 mg, 0.942 mmol, 86% yield) as a colorless oil. Anal. Calcd. for C18H26N2O3 m/z 318.4. found: 319.3 (M+H)+.

Provenance & Evidence