L-Serine → 2-acetamido-3-(6-chloro-5-fluoro-1H-indol-3-yl)propanoic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-chloro-5-fluoroindole (1.8 g, 10.8 mmol) and Ac2O (10 mL) in AcOH (30 mL) was added L-serine (2.2 g, 20.9 mmol), the mixture was heated to 80° C. After TLC indicated the reaction was complete, the mixture was cooled to 0° C., neutralized to pH 11, and washed with MTBE. The aqueous phase was acidified to pH 2 and extracted with EtOAc. The combined organic layers were washed with water and brine, dried with Na2SO4, filtered, and concentrated. The residue was purified with chromatography (Petroleum ether/EtOAc 1:1) to give 2-acetylamino-3-(6-chloro-5-fluoro-1H-indol-3-yl)-proprionic acid as a light yellow solid (1.2 g, 37% yield).

Provenance & Evidence