Pyridine → (2S,5S)-tert-butyl 5-[(carbamoyloxy)methyl]-2-[(2-fluoro-6-nitrophenoxy)methyl]morpholine-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of the product from step 3 (1.6 g, 4.1 mmol) in pyridine (12 mL) was added carbonyl diimidazole (2.0 g, 12.3 mmol) and the mixture was heated in a sealed tube at 60° C. for 2 h. The reaction mixture was cooled to ambient temperature and NH3 gas was bubbled into the solution for 5 min, and the mixture was heated in a sealed tube at 60° C. for 16 h. The reaction was cooled to ambient temperature and the solvent was concentrated under reduced pressure. The residue was purified on a 24 g SiO2 column using a gradient elution of 20-70% EtOAc in hexanes. Fractions containing product were combined and the solvents were removed under reduced pressure to provide the product (1.4 g) as a colorless oil. LC MS: RT=3.60 min, M+H=430 (6 min gradient).

Provenance & Evidence