Hydrochloric Acid → Ethyl indoline-2-carboxylate

Participants

Reaction Steps

A suspension of (S)-indoline-2-carboxylic acid (6.02 g., 36.9 mmol.) in ethanol (70 ml.) at 0° was saturated with hydrochloric acid and allowed to warm to room temperature. After 3 hours at room temperature, the resulting clear, red solution was purged with nitrogen and diluted with ethyl ether (200 ml.). The crystallized product was collected, washed with ethyl ether and dried in vacuo to give 6.43 g. of the title compound as white needles, m.p. 168°-169°; α!D =-70.7° (c=0.68, chloroform). TLC (ethyl acetate-hexane, 1:1) Rf =0.63 (as free base).

Provenance & Evidence