1,2-Dichloroethane → 3-[2-(2-carbazol-9-yl-2-oxo-ethyl)-pentanoylamino]-5-fluoro-4-hydroxy-pentanoic Acid Tert-Butyl Ester

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of (2R)-2-(2-carbazol-9-yl-2-oxo-ethyl)-pentanoic acid (2.94 g, 9.50 mmol), 3-amino-5-fluoro-4-hydroxy-pentanoic acid tert-butyl ester (2.07 g, 9.99 mmol), HOBT (1.41 g, 10.43 mmol), DMAP (1.34 g, 10.97 mmol) and anhydrous THF (40 mL) was cooled to 0° C. then EDC (2.00 g, 10.43 mmol) was added. The mixture was allowed to warm to room temperature during 16 h then concentrated under reduced pressure. The residue purified by flash chromatography (33% EtOAc in 40/60 hexanes) to give the sub-title compound (2.51 g, 53%) as a foam: 1H NMR (400 MHz, CDCl3) δ 0.90-1.03 (3H, m), 1.20-1.90 (13H, m), 2.50-3.00 (3H, m), 3.12-3.26 (1H, m), 3.59-3.80 (2H, m), 4.00-4.68 (3H, m), 6.53-6.89 (1H, m), 7.30-7.52 (4H, m), 7.95-8.05 (2H, m), 8.15-8.26 (2H, m); 19F NMR (376 MHz, CDCl3) δ −229.10, −229.34, −230.95, −231.09.

Provenance & Evidence