Trifluoroacetic acid → 3-{3-[1-(2-Amino-3-methyl-butyryl)-pyrrolidin-2-ylmethyl]-benzofuran-2-yl}-propionic acid ethyl ester

Participants

Reaction Steps

To a solution of 49 (302 mg, 0.6 mmol) in DCM (10 mL) was added TFA (2 mL) at ambient temperature. After 2 h, the solvent was removed under reduced pressure. The residue was dissolved in EtOAc and washed with aqueous NaHCO3, brine, dried over anhydrous Na2SO4, filtered and concentrated to afford 235 mg (97%) of 50 as an orange oil which was used without further purification. 1H NMR (CDCl3, 300 MHz) δ7.86-7.83 (m, 1H), 7.43-7.34 (m, 1H), 7.27-7.19 (m, 3H), 4.49 (m, 1H), 4.14 (q, J=6.9 Hz, 2H), 3.60-3.53 (m, 2H), 3.32 (d, J=12.9 Hz, 1H), 3.12 (app t, J=7.2 Hz, 2H), 2.81-2.74 (m, 2H), 2.42 (app t, J=12.3 Hz, 1H), 2.10-1.91 (m, 2H), 1.74-1.66 (m, 2H), 1.24 (t, J=7.2 Hz, 3H), 1.06-0.99 (m, 6H) ppm. Mass spectrum: m/z 401 [M+H]+.

Provenance & Evidence