Citric Acid → 2-(1-(Tert-butoxycarbonylamino)cyclopropyl)-2-(4-chlorophenyl)acetic acid

Participants

Reaction Steps

tert-Butyl 1-(1-(4-chlorophenyl)-2-oxoethyl)cyclopropylcarbamate (0.64 mmol), 2-methyl-2-butene (1.6 mL, 2.0 M THF solution, 3.2 mmol) and KH2PO4 (0.087 g, 0.64 mmol) were dissolved in t-BuOH (20 mL)-water (6 mL). Sodium chlorite (0.174 g, 1.93 mmol) was added portionwise at 0° C. The mixture was stirred at room temperature for 2 hours and then acidified with 10% citric acid. The reaction was extracted with EtOAc. The combined organic layers were washed with brine, dried and concentrated to give 2-(1-(tert-butoxycarbonylamino)cyclopropyl)-2-(4-chlorophenyl)acetic acid (0.19 g, 91%) as a colorless syrup, which was used for amide coupling without further purification. LCMS: 325.8 [M+H+] (APCI+); Rf: 3.31 min.

Provenance & Evidence