Methanol → Benzoic acid, 2-mercapto-, methyl ester

Participants

Reaction Steps

To a cooled solution of concentrated sulfuric acid (72 g) in methanol (1.5 L) at 0° C., was added 2-sulfanylbenzoic acid (300 g, 1.95 mol) in portions under argon atmosphere. After being refluxed with stirring for 18 hours, the reaction mixture was concentrated in vacuo. The residue was diluted with water (800 mL), basified with a saturated aqueous solution of sodium bicarbonate to about pH 7, and extracted with dichloromethane (600 mL×3). The combined organic layers were washed with brine (800 mL), dried over sodium sulfate, filtered and concentrated in vacuo to afford 300 g of methyl 2-sulfanylbenzoate (yield was 91%) as a light yellow oil, which was used for the next step without further purification.

Provenance & Evidence