Benzyl chloroformate → (3R,4S)-tert-butyl 4-(((benzyloxy)carbonyl)amino)-3-fluoropiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

(3R,4S)-tert-butyl 4-amino-3-fluoropiperidine-1-carboxylate (300 mg, 1.374 mmol) was taken up in DCM (8 mL) and a solution of sodium bicarbonate (346 mg, 4.12 mmol) in water (1 mL) was added. The reaction mixture was cooled to 0° C. and benzyl chloroformate (0.235 mL, 1.649 mmol) was added dropwise. The reaction was stirred at 0° C. for 30 min, then brought to room temperature and stirred overnight. The reaction mixture was diluted with DCM and water, and the organic layer was collected. The aqueous layer was re-extracted with DCM and the organic layers were combined, dried over Na2SO4, filtered, and concentrated. The material was purified by flash column chromatography, eluting with 0-30% EtOAc/Hex. The fractions were combined and concentrated to give (3R,4S)-tert-butyl 4-(((benzyloxy)carbonyl)amino)-3-fluoropiperidine-1-carboxylate (450 mg) as a colorless glass.

Provenance & Evidence