Hydrochloric Acid → (R)-3-(tert-butoxycarbonylamino)-4-(2,4,5-trifluorophenyl)butanoic acid

Participants

Reaction Conditions

Reaction Steps

1.31 g of (R)-t-butyl 3-(t-butoxycarbonylamino)-4-(2,4,5-trifluorophenyl)butanoate, 16 mL of methylene chloride, and 16 mL of trifluoroacetic acid were added to 100 mL flask and the resulting reaction solution was stirred for 6 hours. After completing the reaction, the reaction solution was concentrated under reduced pressure and 16 mL of methanol was added to the concentrated residue. The reaction solution was cooled to 0° C., 2.82 g of sodium hydrogen carbonate and 0.77 mL of di-t-butyl dicarbonate were added, and then stirred for 6 hours while the reaction temperature was naturally increased to room temperature. After completing the reaction, the reaction solution was concentrated under reduced pressure; then 30 mL of ethyl acetate and 30 mL of water were added; and then stirred for 10 minutes. An aqueous layer was isolated, cooled to 0° C., and then 2 N hydrochloric acid aqueous solution was dropped to adjust to pH 3-4. The aqueous layer was extracted with methylene chloride:methanol=10:1 solvent, dehydrated with magnesium sulfate, and then concentrated under reduced pressure to obtain 828 mg of a title compound.

Provenance & Evidence