Hydrochloric Acid → Phenyl 2-mercaptobenzoate

Participants

Reaction Steps

In a 250 ml three-necked flask a mixture of 69.4 g (0.45 mol) of thiosalicylic acid and 42.3 g (0.45 mol) of phenol is melted at 135° C. with stirring. Then, at 125°-130° C., 24.5 g (0.16 mol) of phosphorus oxychloride are added dropwise, HCl being liberated. When the addition is complete (about 15 min.) stirring is carried out for 30 minutes. The resulting dark-brown clear solution is stirred into 500 ml of water, a brown oil separating. This oil is taken up in ethyl acetate. The organic phase is extracted three times by shaking with soda solution, washed with water, dried and concentrated to a residue. The residue, which still contains phenol, is purified by distillation. The crude product is recrystallised from 250 ml of absolute methanol in the presence of activated carbon. The product is obtained in the form of colourless crystals having a melting point of 89° C. The yield is 36.0 g (=35% of the theoretical amount).

Provenance & Evidence