Hydrochloric Acid → 3-Bromo-4-methylbenzene-1-thiol

Participants

Reaction Conditions

Reaction Steps

A cooled (−15° C.) solution of 3-bromo-4-methylaniline (ABCR; 2.0 g) in a 6N solution of HCl in water (30 mL) was treated drop-wise with a solution of sodium nitrite (1.78 g) in water (10 mL). The reaction mixture was stirred for 30 mins. The resulting clear solution was added dropwise to a stirred solution of O-ethyl xanthic acid potassium salt (6.1 g) in water (25 mL). The mixture was then heated to 80° C. for 15 minutes. The mixture was then cooled and extracted with diethyl ether twice. The solvents were evaporated under reduced pressure to give a residue, which was treated with a solution of KOH (6.1 g) in 95% ethanol (55 mL) and heated to reflux for 10 h. The reaction mixture was diluted with water and acidified with conc. HCl to pH 3 and extracted with diethyl ether. The organic layer was washed with water, brine and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel), eluting with petroleum ether. This product obtained was triturated with hexane to give the title compound (1.5 g, 70%) as an off-white solid.

Provenance & Evidence