Trifluoroacetic acid → 3-[4-Hydroxy-2-(2-isopropoxycarbonylamino-ethyl)-phenyl]-propionic acid methyl ester

Participants

Reaction Steps

A solution of 3-[2-(2-tert-butoxycarbonylamino-ethyl)-4-hydroxy-phenyl]-propionic acid methyl ester (282 mg, 0.876 mmol; Example 544, Step E) in CH2Cl2 (10 mL) at ambient temperature was treated with TFA (5.0 mL), stirred for 60 min, and concentrated. The residue in CH2Cl2 (10 mL) was treated with triethyl amine (2.0 mL) and iso-propyl chloroformate (0.97 mL, 1.0 M in toluene). The reaction mixture was stirred at ambient temperature for 16 h and concentrated. The crude material was purified using silica gel chromatography (50% EtOAc/hexanes) to yield the title compound (180 mg, 67%).

Provenance & Evidence