Dimethyl Sulfate → (2S)-2-[(tert-Butoxycarbonyl)amino]-3-(3,5-difluorophenyl)propionic acid methyl ester

Participants

Reaction Steps

(2S)-2-[(tert-butoxycarbonyl)amino]-3-(3,5-difluorophenyl)propanoic acid (I, 5.0 g, 0.017 moles, 1.0 equivalent) and potassium carbonate (2.5 g, 0.018 moles, 1.1 equivalent) and DMF (100 mL) are mixed. To this heterogeneous mixture is then added dimethyl sulfate (1.6 mL, 2.1 g, 0.017 moles, 1.0 equivalent) and the contents are then stirred at 20-25° overnight. Once the reaction is complete as measured by HPLC, ammonium hydroxide (10%, 20 mL) is added and allowed to stir for 1 hr. The contents are stirred for 30 min then cooled to 0° and filtered. The solids are washed with cold water (20 mL) and dried under reduced pressure to give the title compound.

Provenance & Evidence