Triethylamine → (S)-Methyl 2-((tert-butoxycarbonyl)amino)-3-(4-(((trifluoromethyl)sulfonyl)oxy)phenyl)propanoate

Participants

Reaction Conditions

Reaction Steps

Trifluoromethanesulfonic anhydride (0.85 mL, 5.1 mmol) was added to a solution of methyl (2S)-2-[(tert-butoxycarbonyl)amino]-3-(4-hydroxyphenyl)propanoate (1 g, 3 mmol) (Aldrich, Cat 469106) and triethylamine (1 mL, 10 mmol) in methylene chloride (30 mL) at −78° C. The reaction was stirred for 1 h. at −78° C. Saturated NaHCO3 was added and the reaction was extracted with dichloromethane. The organic phase was washed with saturated brine, dried over magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by Flash chromatography on a silica gel column (EtOAc:Hexane, 1:3 to 1:1) to obtain (S)-2-tert-butoxycarbonylamino-3-(4-trifluoromethanesulfonyloxy-phenyl)-propionic acid methyl ester (1.2 g, 80%) as light yellow oil. Analytical LCMS (M+H-Boc)+: m/z=327.9.

Provenance & Evidence