Isopropyl chloroformate → 3-{2-(2-Isopropoxycarbonylamino-ethyl)-4-[2-(5-methyl-2-phenyl-oxazol-4-yl)-ethoxy]-phenyl}-propionic acid

Participants

Reaction Steps

A solution of 3-{2-(2-amino-ethyl)-4-[2-(5-methyl-2-phenyl-oxazol-4-yl)-ethoxy]-phenyl}-propionic acid methyl ester (26 mg, 0.064 mmol) in CH2Cl2 (2 mL) at 0° C. was treated with TEA (0.2 mL) and isopropyl chloroformate (0.13 mL, 1.0 M in ether). The resulting mixture was allowed to warm gradually to ambient temperature. After 2 h, the mixture was concentrated to a residue, which was purified by silica gel chromatography (hexanes/EtOAc 7/3) to afford the isopropyl carbamate as a colorless oil. 1H NMR (400 MHz, CDCl3): δ 1.19 (d, 6H, J=5.9 Hz), 2.42 (s, 3H), 2.54 (t, 2H, J=7.8 Hz), 2.79 (t, 2H, J=6.8 Hz), 2.89 (t, 2H, J=7.8 Hz), 3.05 (br s, 2H), 3.38 (br s, 2H), 3.60 (s, 3H), 4.26 (t, 2H, J=6.8 Hz), 4.68 (br s, 1H), 4.89 (q, 1H, J=6.4 Hz), 6.70 (br s, 1H), 6.71 (d, 1H, J=8.3 Hz), 7.05 (d, 1H, J=8.3 Hz), 7.47 (m, 3H), 8.10 (m, 2H).

Provenance & Evidence