Potassium Hydroxide → 4-Mercaptophenylacetic acid

Participants

Reaction Steps

To a solution of 2-(4-((ethoxycarbonothioyl)thio)phenyl)acetic acid (50.0 g, crude, 0.195 mol) in EtOH (180 mL) was added a solution of KOH (40.5 g, 0.724 mol) in water (180 mL). The mixture was stirred at reflux overnight. The mixture was concentrated under reduced pressure to remove EtOH. The aqueous phase was adjusted to pH=1˜2 with conc. HCl. The aqueous phase was then extracted with ethyl acetate (3×200 mL). The combined organic layers were dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure to afford crude 2-(4-mercaptophenyl)acetic acid (32.0 g, 98%) as a gray solid, which was used for next step directly without further purification. 1H NMR (purified by pre-TLC, CD3OD, 400 MHz): δ 7.23 (d, J=8.4 Hz, 2H), 7.15 (d, J=8.0 Hz, 2H), 3.54 (s, 2H).

Provenance & Evidence