Indole-3-Acetic Acid → Benzyl (1H-indol-3-yl)acetate

Participants

Reaction Steps

Indole 3-acetic acid 1 (9.45 g, 0.054 mol) was dissolved in methanolic benzyl diethyl anilinium hydroxide (0.54 mol) and the solvent removed in vacuo. The oily residue of the benzyl dimethyl anilinium salt was agitated with benzene, the benzene evaporated and the salt refluxed in toluene (170 ml, 1 h). Traces of unreacted acid and dimethyl aniline by-product were removed by extracting the toluene solution with water, dilute hydrochloric acid (1N) and water. The organic layer was dried over sodium sulphate and concentrated in vacuo to obtain the crude product. Final purification was obtained by crystallization in EtOAc:Hexane to give 11.52 g (80%) indole-3-acetic acid benzyl ester 13 as white crystals (melting point 71°-72° C.); IR (Nujol, cm-1); 3 400, 1, 720; 1H-NMR (CDCl3,δ): 3.8 (s, 2 H), 5.1 (s, 2 H) 6.8-8.0 (m, 1 H).

Provenance & Evidence